Breathing Treatment

Roadkill reporters needed

2012-01-25T21:01:00.000-08:00

This [roadkill] is a relatively new source of fatality; and if one were to estimate the entire mileage of such roads in the state, the mortality must mount into the hundreds and perhaps thousands every 24 hours." (Joseph Grinnell, 1920) found on wildlifecrossing.net.

Crowd sourcing has yet another use. It turns out that there is significant scientific interest in roadkill. For example,

Over the last few decades, Eastern Fox Squirrel have been migrating from their original sites of invasion in California (Bay Area and Los Angeles) toward other areas, where they tend to displace the native Western Grey Squirrel. Because these two species are commonly-reported as roadkill, we can study their co-distribution and where Eastern Fox Squirrel have successfully invaded or are invading the habitat of Western Grey Squirrel. As you can see from the map below, there are several areas where only Eastern Fox Squirrel or Western Grey Squirrel occur and other areas, such as Sacramento, Santa Cruz, and Monterey Bay where both species occur. These mixing zones may indicate active invasion by the non-native species. (CROS Annual Report)

Knowing the locations of roadkill hotspots will also allow researchers to recommend best practices for road builders.

The states of California and Maine are now using an online reporting tool to track road kill. Anyone in those states can report identifiable roadkill using a web interface at http://www.wildlifecrossing.net/california/node/add/roadkill (registration required).

Is there an app for that? Turns out that the plans are in the works for one.

Rain 1.6"; season total 5.11"

2012-01-24T22:06:00.001-08:00

We had the good fortune to pick up some rain over the weekend and Monday, bringing the season total to about 5" at my new house.

On 22 Jan in the morning, I measured 0.70" at my house (weather.com had it at 0.54" for my zip code) and 0.30" at the San Pedro annex.

We had a day of respite from rain and then on Tuesday I measured 0.9" in my backyard that had fallen the day before. For the same time period the San Pedro annex was about 0.7". Weather.com put this rainfall at 0.6" in my zip code, so it looks like I'm running a bit ahead of the official figures.

A high degree of variation is expected between the San Pedro annex, my house, and the official figures for my zip code due to the large variation in topography in the area.

Some unreported (on this blog) previous rainfall:

11-Dec 0.60"
17-Dec 0.10"
18-Dec 0.01"

- Posted at great expense from my iPhone

Knitted chain link

2012-01-19T19:32:00.000-08:00

This is firmly in the camp of "What will they think of next?".

This isn't breaking news, but it's worth retelling. From http://www.architerials.com/:

Dutch design firm Demakersvan has produced a line of chain link fence that incorporates the ancient craft of lace-making into the fabrication of industrial chain link fence, taking something which was meant to be purely functional and gently encouraging it to be decorative. Think of Lace Fence as your Blanche Devereaux fencing option: it’s a flirty southern charmer with a stubborn streak and perhaps a little bit of a temper.

Get more information from the source, lacefence.com

Napa river walk

2012-01-19T00:03:00.001-08:00

Juli and I had a nice vacation in northern California over New Years. We stayed in the town of Napa, which has a certain amount of appeal all on it's own, even leaving aside the fact that it's the gateway to the Napa Valley wine region. Napa celebrates its river in ways that we don't see much of here in Los Angeles.

Near the place we stayed is a 1.2 mile paved trail that runs along the Napa river.

Interesting side paths go down to the river's edge.

I think we stayed at River Pointe - a timeshare. The buildings are all mobile and the infrastructure is designed to accommodate seasonal flooding. These fences pivot as water washes by but that wasn't a concern for us: all the locals were commenting on the lack of rain when we were there.

- Posted at great expense from my iPhone

Calflora Mobile Search

2011-11-23T16:50:00.000-08:00

Following on the previous blog post, also available from Calflora Calflora Mobile Search for plants, an interface to the Calflora database for mobile devices. Click on a plant name, and you will see one or two photos of the plant. Works on Android and iPhone. Check the current location box and (courtesy of HTML5) it will limit the search to plants observed growing near wherever you are.

Calflora Observer app for Android and iPhone

2011-11-23T16:47:00.000-08:00

Back in last year's blog post "Ready to go live with What's Invasive!" I wrote about a smart phone app called What's Invasive!, an application used for mapping invasive plants.

The makers of What's Invasive! have teamed with Calflora to make the Calflora Observer Observer smart phone application with the purpose of making observations of wild plants, including photos, on your Android or iPhone. It's a free download and I'll be firing it up soon. Whereas What's Invasive relied on user- or community-defined plant lists, Observer allows reporting of any plant.

This application makes it easy for you to report the species name, date, and location of over 10,000 California native and non-native plant taxa. You can also add a photograph to a report, and share it with others later to confirm identification. Your reports are transmitted wirelessly to the Calflora database, where you can edit them and see them on a map.

To use the application, you need to register as a contributor. When you upload observations from your phone, they go into the database in an unpublished state. You can use the My Observations application to edit your observations, and when they are ready, publish them so that they are visible to other Calflora users.

This type of map is useful for wildlands and green space management. Detailed iPhone instructions for use are available.

Rain 0.875"; season total 2.805"

2011-11-21T06:00:00.000-08:00

We had a nice rain storm yesterday and accumulated 0.875" in my back yard over the day.

Recent rains have been:

6 Nov 0.24"
12 Nov 0.26" fell the day or night before
13 Nov 0.01"
21 Nov 0.875"

The ants go marching

2011-11-17T17:44:00.000-08:00

I got this link to "17,000 Species in the Great Smoky Mountains. And Counting" (http://www.metropulse.com/news/2011/nov/16/17000-species-great-smoky-mountains-and-counting/) from my native plant listserv courtesy of Jeffrey Caldwell, along with an interesting observation from that report:

“...most of the plant species that you see in the Great Smoky Mountains National Park rely on ants to disperse their seeds,” Sanders says. “So one of the things we did was just put out seeds and look at what happened to them. And 166 out of 167 times, one ant species carried the seed away. So even though there there’s a lot of biodiversity in the Smokies, there’s some species that do a lot.” If one of those super-species was threatened by changes in its habitat, it could have wide-ranging consequences.

Most native plant fanciers appreciate the role of insects in the food web, but the role of ants was previously unknown to me. I seem to recall that a native (and distinctly larger) black ant was more plentiful when I was growing up, but I have hardly seen them recently. I think they've been supplanted by Argentine ants all along the western coast of the US.

Wikipedia confirms that Argentine ants win battles for turf from native ants simply because they act as one continental-wide (actually a global) hive*. An illustration of this is that if you take an Argentine ant from San Diego and drop it into a hive in Los Angeles, it will fit right in. I don't think our native ants have this advantage: an interloper from another hive will be killed. So ultimately Argentinian ants will win turf battles by virtue of their overwhelming numbers and disinclination to fight among themselves.

The ants' reduced genetic diversity, from the small population of ants that initially invaded the U.S., allowed a giant "supercolony" of closely related ants to grow unchecked from San Diego to Ukiah, 100 miles north of San Francisco.link

Apparently, in their native areas they are not as populous as they are in California. Researchers suspect this is due to hive competition. I wonder if we could find or cultivate a sufficiently different Argentine ant, release it into the "wild" and that would keep the species in check by internal warring?

So there's the seed dispersal issue: I'll bet Argentine ants don't disperse seed as well as our native ants. But there's also other food web issues:

In a series of laboratory experiments [scientists showed that] baby horned lizards fed a diet of insects typical of a community after invasion of Argentine ants cannot grow and, in many cases, decline in weight. But when their diet is switched to insects typical of an uninvaded community, the scientists found that the baby horned lizards grow normally. link

So maybe the sign of a really robust Ca native ecosystem is no Argentine ants?

*Wikipedia: According to research published in Insectes Sociaux in 2009, it was discovered that ants from three Argentine ant supercolonies in America, Europe, and Japan, that were previously thought to be separate, were in fact most likely to be genetically related. The three colonies in question were one in Europe, stretching 6,000 km (3,700 mi) along the Mediterranean coast, the "Californian large" colony, stretching 900 km (560 mi) along the coast of California, and a third on the west coast of Japan.

Based on a similarity in the chemical profile of hydrocarbons on the cuticles of the ants from each colony, and on the ants non-aggressive and grooming behaviour when interacting, compared to their behaviour when mixing with ants from other super-colonies from the coast of Catalonia in Spain and from Kobe in Japan, researchers concluded that the three colonies studied actually represented a single global super-colony.

The researchers stated that "enormous extent of this population is paralleled only by human society", and had probably been spread and maintained by human travel

Native plant detective story - Aesculus californica

2011-11-09T17:31:00.000-08:00

I was leaning against the bar in a speakeasy in Malaga Cove, waiting for Juli to finish her Christmas shopping, when a girl got up from the table where she had been sitting with three other people and came over to me. She was small and blonde, and whether you looked at her face or at her body in powder-blue sport clothes, the result was satisfactory. "Aren't you Brent?" she asked.
   I said: "Yes."
   She held out her hand. "I'm Dorothy Aesculus. You don't remember me, but you ought to remember my father, Bucky Aesculus. You-"
   "Sure," I said, "and I remember you now, but you were only a kid of eleven or twelve then, weren't you?"
   "Yes, that was eight years ago. Listen: remember those stories you told me? Were they true?"
   "Probably not. How is your father?"
   She laughed. "I was going to ask you. Mamma divorced him, you know, and we haven't heard from him since 2005. Don't you ever see him?"
   My glass was empty. I asked her what she would have to drink, she said Scotch and soda. I ordered two of them and said: "No, I've been driving and hiking all around, but I haven't seen him."
   She said slowly: "I'd like to see him. Mamma would raise hell if she found it out, but I'd like to see him."
   "I would too. And?"
   "He's not in the phone book or city directory."
   "Try his lawyer," I suggested.
   Her face brightened. "Who is he?"
   "It used to be a fellow named Jep-something-or-other-Jepson, that's it, Jepson Herbarium. He was in the Singer Building."
   "Lend me a nickel," she said, and went out to the telephone.*

Well, it wasn't as dramatic as all that.

One of the fun things about a new garden is the time you spend before you plant, planning the whole thing. Gardening is work and you expect to break a sweat doing it. But in the planning stages you can live in a sort of Platonic ideal of a garden - filled with possibilities and not one drop yet of sweat.

I was spending some time considering the merits of California Buckeye (Aesculus californica) as a yard tree and went looking for data supporting its presence on the Palos Verdes Peninsula. It's a signature tree of my summer travels to northern California and I like it a lot. Aesculus is one of the hallmarks of my summer travels with great looking new foliage, followed by 6 inch or longer flower spikes, and a distinctive early browning of leaf color before it loses them all.

However, I was regretful that I hadn't noted any in my travels around my neighborhood. They are distinctive trees. A few idle minutes with my underworld informants told me that there was information to be had in the Jepson Herbarium. Sure enough, an occurrence was noted near Malaga Cove, but there was only one reported sighting from 2005 that noted only two trees, so anything could have happened in the intervening years! Were they the last ones? I got a little excited about rediscovering what seems to be a rarely occurring native tree in Palos Verdes. Maybe there was no trace left? Maybe there was only one or none left! The thrill of the hunt is similar to that of geocaching, except that the trees I was looking for could be well hidden or even extirpated.

Hot on their trail, this morning I went on a little walk and found what I think were two spindly looking, multi-trunked, Aesculus. I saw no dried flower spikes or fruits which would have made identification easier, possibly due to the poor health of the trees. However, I had also expected either bare branches or completely brown foliage at this time of year based on what I know of the tree in N. California. What I found were leaves still on the tree with a color that I'd expect to see no later than mid summer in hotter inland N. California areas. See the photo of a typical leaf that I found on the ground nearby. The local climate is much cooler in summer and warmer in winter than N. California, so perhaps that explains the late autumn colors. Otherwise, it seems to match to Aesculus Californica. I've emailed some local experts for more info.

Are these are in fact PV-native or transplants? Truly local plants will probably have genetic variations that are specific to their regional microclimate. Are there other stands of Aesculus elsewhere on the Peninsula? Seems like there's a sequel in the making.

*Stolen without regret from Dashiell Hammett's The Thin Man

Rain 0.20"; season total 1.42"

2011-11-05T18:44:00.000-07:00

We had rain again last night of 0.20". I had regretted not having my rain gauge out in the yard for the first storm of the season in early October, but I found an old dog bowl in my back yard after that storm and measured the water in it to to get a handle on that storm's rain: 1.22 inches! Based on the location of the dog bowl (out in the clear) I think it was a true reading even though 1.22" seems like a lot of rain. I'll go with it for now as the official first rainfall of the season at my new home and feel good about having a complete record for this season.

The San Pedro annex, only 10 minutes by car away, received 0.35" of rain to my 0.20".

Local trails and busy but not forgotten

2011-10-26T18:44:00.000-07:00

I'm busy doing some things other than blogging. One of the fun things I'm doing is familiarizing myself with local trails. It turns out there are plenty of obscure and undocumented ones, such as the "Mailbox Trail" which quickly devolves into a single track along the edge of George F Canyon.

George F turns into another canyon system further along, and the trails are wide and well maintained in this area (for horses).

That's Toyon (Heteromeles arbutifolia) on the left with the red berries and Lemonade Berry (Rhus integrifolia) looming over the right hand branch of the trail. They're easy to tell apart this time of year with the red berries only on Toyon, which is also known as Christmas Berry. When they are not in bloom, I think the easiest way to tell them apart is by the leaf edges: Serrations on the Toyon, smooth or wavy on Lemonade Berry. This seems to be locally true, anyway.

I have been assured that all trails are public access, yet already I've run into what appear to be bogus trail closings promulgated by local homeowner groups (thinks to self, "Hmm. I don't see the advertised trail hazard that motivated trail closure with not one but two chain link fences across the trail. Curious - these fences seem designed to cut off down-trail access into a gated community that is advertised as open at the public-access trailhead. Wow, even the horsemen passing within eyeshot of the trail closure don't seem to think there's a hazard.")

I sense some advocacy in my future. Until then, I'm just a quiet trails anthropologist and I'll keep a photo record documenting trail conditions without trying to perturb the system.

I'll be back in a bit to tell you more about native plants - I have tremendous plans for my new yard. Until then, I'm a bit busy. See you on the trails.

Charlotte to Charlie to Charles to Chuck

2011-10-14T17:36:00.000-07:00

There were several if these large spiders around the house a couple weeks ago. They were at my old house too until they mysteriously disappeared - I think the neighbor sprayed.

This one started as a relatively petite Charlotte and ended as thuggish Chuck over a couple week period of time.

The camera angle makes it appear that there's a large blurry spider on my lawn, but it's really just 50 cent piece sized spider in the foreground of the shot.

- Posted at great expense from my iPhone

First rains of the winter

2011-10-05T10:47:00.000-07:00

I'm happy that we're getting some rain. Often it will rain in October and then be dry again until much later in the year, so an early start on the winter rains isn't necessarily a harbinger of a wet winter. Traffic was typically slow yesterday morning and this morning due to our first rain of the year: We had a small amount of rain yesterday A.M. and more today that appears to be making more of a lasting impression.

My new house is in a rain "shadow" on the east side of a coastal hill. As I drive around the hill on which I live each morning, I've noticed that my east facing, leeward, side of the hill seems to consistently have less moisture than the ocean side. This seems an intuitive result for storms arriving from the ocean and it's also true for fog, which can be a significant contributor to soil moisture.

Sadly, my rain gauge is not out in the yard yet so I'll have to make an educated guess on the precipitation from this storm. I would have liked to start the winter with some solid measurements.

Addendum: I found an old dog bowl in the yard with 3.1 cm of water in it, so I'm going with rainfall of 1.22". That's a lot!

George F canyon

2011-10-01T10:11:00.001-07:00

Click for a full panorama.

- Posted at great expense from my iPhone

Location:Lomita,United States

Out of the Box: California native plants for hedges

2011-09-13T18:01:00.000-07:00

Joan Bolton of Santa Barbara writes a nice blog about gardening and garden design. A recent blog post called Splendid Hedges has recommendations for California native plant hedges. Joan recommends Lemonade berry (Rhus integrifolia), Hollyleaf cherry (Prunus ilicifolia), Catalina cherry (Prunus lyonii), Ceanothus 'Julia Phelps', Toyon (Heteromeles arbutifolia), Howard McMinn manzanita (Arctostaphylos densiflora ‘Howard McMinn’) and Oregon grape (Berberis aquifolium) as hedges.

I guess that most people think big when they think of hedges, even though the ~1 foot tall clipped box (Buxus) hedges used as borders and in European knot gardens are equally hedges in my mind. Here's a nice photo that I found at Boxtrees Nursery (in England of course).

Maybe there's no smallish California native plant that lends itself to that style of hedge since the smallest pruned and maintained size among the plants that Joan recommends are the last two, which she says can be maintained at 6 feet tall and 4 feet wide. Or maybe with our high population density we're really talking about privacy and screening views when we in California talk about hedges. I looked briefly online for examples of California natives in a tightly sheared hedge, but didn't find any pictures. I do recall pruning a Lemonade Berry hedge with loppers and an electric clipper at a friend's house in Hope Ranch when I was a teen.

Scanning the archives of my (northern California based) listserve I came up with these suggestions for hedge plants:
Rhus integrifolia (the previously mentioned Lemonade Berry)
Galvesia speciosa (some selections will grow with a more compact habit than others)
Bacharris pilularis (Coyote Bush)
Garry elliptica 'Evie' or 'James Roof' or even the straight species
Rhamnus crocea can be used as a very formal hedge
Ribes viburnifolium (Evergreen Currant)
Cercocarpus betuloides (Mountain Mahogany)
Garrya elliptica
Arctostaphylos 'Sunset' was recommended instead of McMinn as it was said to be more hedge-like and not require much in the way of pruning
Coffeeberry

Las Pilitas nursery, always a source of interesting information, has a section on hedges and screens. They include some more iconoclastic selections.

Finally, in a related blog post earlier, Naked behind a screen in the garden, KarenH suggested that I look at a Los Angeles area online native plant resource called Project SOUND, which I have mentioned very occasionally here. It's nice to see that it's up and running and thank you KarenH.

Garden miscellany

2011-09-08T18:07:00.000-07:00

Here's an interesting garden juxtaposition. To set the stage: This photo was taken at the LA County Museum of Art. The permanent garden that lines the walkways between buildings has a high level of LA-style design: Bright red painted steel uprights for the walkway roof, exceptionally straight and perfectly aligned COR-TEN steel retaining walls, COR-TEN steel raised planters that resemble wooden planter boxes, and a range of imported plants starting with turf grass and ending with palms.

Surrounding the BCAM building and LACMA's courtyard is a 100 palm tree garden, designed by artist Robert Irwin and landscape architect Paul Comstock. Some of the 30 varieties of palms are in the ground, but most are in large wooden boxes above ground. - Wikipedia (but of course those wooden boxes are actually steel that resembles wood boxes, so Wikipedia is wrong in that small matter. Also the palms are not all, strictly speaking, palms.)

Given the high level of design and the mix of imported plant materials I thought that this reindeer (clearly made from artificial plant materials, surmounting a "bark" hill that is dotted with plastic flowers, and surrounded by a synthetic box hedge) was a sly comment on the permanent garden. Alas, it is a marker for the entrance to the Tim Burton exhibit and destined to move on when the exhibit closes on Oct 31. The reindeer was a prop in the movie Edward Scissorhands.

Tim Burton has a fairly prolific career so there was ample material but when it was all said and done I was left feeling like I'd had a Dodger Dog and a large Coke instead of a five course gourmet meal.

Here's another "garden" looking north from the end of the Palos Verdes peninsula. I believe that's Rhus integrifolia (Lemonade Berry) in the foreground. I saw a large Mimulus on the cliffs as well in full late summer dormancy.

Landscape Resource

2011-09-08T18:05:00.000-07:00

I just found what looks to be a useful online plant palette design tool associated with a website called Landscape Resource. It has an obvious URL (http://www.landscaperesource.com/) that I can't actually make an active link since I'm bound by the site's overly broad terms and conditions which state in part,

8. You may not create a link to this website from another website or document without Landscape Resource's prior written consent.

Maybe I'm the only one who reads those things. I emailed them and had a speedy and friendly reply from Rob Maday who told me that he agreed and that the Terms and Conditions were under review.

The site looks promising enough that you should check it out. Hopefully, you'll someday soon be able to refer traffic directly to their site.

World's largest and most florific Cal. Poppy

2011-09-05T11:27:00.001-07:00

That's one California Poppy (Eschlozia californica maritima) plant overwhelming a downhill rose. I posted on this poppy earlier in May! of this year and it's amazing that it's still producing blooms.

- Posted at great expense from my iPhone

Naked behind a screen in the garden

2011-09-01T18:01:00.000-07:00

I stumbled across a good article about Naked Ladies the other day - Amaryllis belladonna, not Playmates. The author, Joan Bolton, comes from nearby Santa Barbara so her gardening know-how would appear to translate well to Los Angeles. Browsing her blog I quickly stumbled across some information that I thought would be more immediately useful in a post called Splendid Hedges. Recall that I just posted how I need to hide a neighbor's front yard with a hedge or screen.

Here's the naked view from my front yard this morning.

My property is slightly higher than the neighbor's and the scrawny roses currently planted along a low wall don't provide enough height to hide the garbage cans and piles of brick in the neighbor's yard. There's also no amount of planting that I can do where my walkway meets the retaining wall, and that's the area that I'd like to screen the most. On the one hand, I admire the neighbor for having the balls to buck the wall to wall green grass trend and plant an orchard instead. On the other hand, I don't want to look at their garbage can storage area.

For purposes of continuity, I briefly considered extending the fantastic (you'll have to imagine the sarcasm in my voice) Eugenia topiary into hedges or adding more Eugenia as a dedicated hedge, but after about a nanosecond I concluded that I was going to demo the incongruously-placed and uninteresting layer cake topiary. (A highly innovative stacked sphere topiary is visible at left in the above picture. Imagine many similar but purposeless topiary sentinels, like Easter Island statues. Ugh.) So, no Eugenia hedge for me.

I then spent a good long time thinking and reading about native plant hedge solutions, but it turns out that native hedge plants may not be the best solution. Most hedge plants tend to be taller and broader than I need or want and they don't address the gap where the concrete walkway abuts the retaining wall. But, while I thought I was thinking about hedges, my mind apparently was spinning up other ideas.

It turns out that there may be a partial hardscape solution: Extending the ornamental fence that already exists on the front side of my property might do the trick, provided I grow low arching shrubs in front or climbing plants on it. This would definitely be a harmonious solution that would take up the minimum of space. There may even be standard fence panels that are a bit taller than those I currently have that would give it a bit more screening. The picture below is a crude mockup of how it might work.

Extending an imaginary line from the top of the large white-flowered rose in that picture says that I would only need to overtop the fence by a foot to two feet to get all the screen that I wanted.

I haven't had a chance to closely observe it, but I think that the sun exposure in this area of my garden is partial - it's shaded by the Jacaranda street trees in the PM and by the house in the AM. Foggy days are likely too. This kind of exposure is consistent with the mixed success that the previous owners apparently had with roses in this area.

To cover the planting gap where the concrete meets the wall I'll want vines or arching growth that I can tie or train to the fence. This narrows the selection process nicely. This seems to be the short list:

Calystegia macrostegia (Morning Glory Vine). My locally native variety has small white flowers but the Channel Island selection "Anacapa Pink" has large pink veined flowers. Evergreen.
Clematis ligusticifolia (Virgin's Bower or Yerba De Chiva). Winter deciduous.
Lonicera hispidula (California or Pink Honeysuckle) - a vine-like shrub that has relatively sparse growth. Semi-evergreen.
Vitis 'Walker Ridge' (Walker Ridge Wild Grape). Smaller selection. Winter deciduous.

Put one of those on a small fence and I won't feel so naked any more.

Can I compost my whole yard?

2011-08-18T06:00:00.000-07:00

I'd love to unleash a giant mutant lawnmower / chipper / shredder robot on the whole yard, make a giant pile of compost*, and start fresh with the gardens. Doing something similar by hand is a daunting task; there's some exciting possibilities in my new gardens, but it will take some heavy demolition work to get to a useable state.

Some pictures:

Some animal (raccoon or possum most likely) is eating my peaches :(

Here's a back yard panorama view from the living room which spans about 180 degrees. Click to see the whole thing. There's a view hidden behind the east-facing hillside of overgrown oleander*, fig, and Brazilian pepper (behind the white structure that houses the spa pump). Who knows what else I'll find there?

The old swimming pool has been filled in, as you can see above. This is a good thing in my book. The location of the old pool, near the house, and its well-defined shape suggest a more formal garden could go here. Instead, I have an out of control Ficus tree and Agapanthus galore. Get set for demolition!

The property line cinderblock wall on the left needs to be softened. I do believe that good walls make good neighbors, but this needs a little help, beyond the overgrown rosemary bush visible behind and to the left of the ficus tree.

The giant Brazilian pepper tree at far right shades a spa. It's probably the progenitor of all the feral pepper trees on the hillside. There's lots of concrete that I could strategically cut one of these days.

A small hedge at the far side of the lawn would screen the view of the neighbor's trash cans and yard. Why didn't someone plant Agapanthus there instead of those scrawny roses?

Ah, home sweet home.

The front yard I'll leave in peace for at least a while. This driveway-adjacent hillside of yet more Agapanthus and featuring the Christmas tree will no doubt be the first area to go, but probably later rather than sooner. I'll do some selected editing in the rest of the front garden areas, but I won't plan to touch them for a while.

The other side yard has some fruit trees, but I don't know that they get enough sun because of what used to be a live Christmas tree that the previous owner planted outside at his daughter's request. I think it's shading this side yard a bit much. There's also a drainage problem here. I'll need to give area some thought, but no immediate action: Maybe a retaining wall and drain?

Above: Side yard with fruit trees (3 or 4 citrus, fig, and peach) and a grape vine. Oh, don't forget more Agapanthus.

Above: "Christmas" tree at right in front of fence.

One side yard has garage access and serves as a service yard. There's some overgrown trees and shrubs here. In the interest of keeping it simple and going with what is already working, I think its future holds fewer trees and shrubs and more Bougainvillea.

*The answer to whether I can compost oleander, all parts of which are toxic if ingested, seems to be yes according to Google consensus. A mailing list post and article by Deborah Mills here seems to clearly state the case for using oleander mulch.

...the problem with using Oleander in the compost is if the leaves are not completely decomposed and a piece of it happens to get mixed in with the produce, for example, loose leaf lettuce, and that piece of Oleander leaf gets ingested. Once the leaves are completely decomposed they don't pose a hazard. Usually I recommend that Oleander compost is great for landscapes and use with caution in vegetable gardens for the reason above.

Not convinced? See also James A. Downer and Arthur Craigmill (Composting is an effective method means of destroying one of the toxic glycosides in oleander. The composting process causes a rapid decline in oleandrin concentration and eventually its complete disappearance from the compost.) Separate studies confirm that oleadrin is not taken up by plants.

Franciscan manzanita video

2011-08-12T13:48:00.000-07:00

Back from the Brink: for the last wild franciscan manzanita

It has long been known that the Presidio is home to the last Raven's manzanita on earth. Surprisingly, a chance discovery made in 2010 during the Doyle Drive reconstruction project revealed the existence of the Franciscan manzanita, thought to have been extinct in the wild for more than 70 years. This 23-minute film by San Francisco filmmaker Melissa Peabody tells the compelling story of these two icons of California's natural heritage. Produced 2011. Presidio Trust.

All new garden challenges

2011-07-22T09:32:00.001-07:00

I haven't been posting much because I've been super busy trying to finesse a change of address. There's going to be all sorts of new native plant opportunities: an east-facing hillside covered with Oleander and Brazilian Pepper has the most potential for native habitat and maybe a small vineyard while an old swimming pool that has been filled will offer an opportunity for a more formal garden closer to the house. This still isn't certainty yet, so I'm treading lightly in terms of my planning and hopes.

See you in the garden.

Location:Rancho Palos Verdes

View from tent 35

2011-06-22T22:24:00.001-07:00

Down by the creek.

- Posted at great expense from my iPhone

Recent Tritelia laxa garden history

2011-06-14T21:45:00.000-07:00

'Ithuriel's Spear'

Below: on or about June 12th.

- Posted at great expense from my iPhone

Blog Hiatus

2011-06-14T01:02:00.001-07:00

I may be posting infrequently for the next couple weeks. Take care!

- Posted at great expense from my iPhone

Madrona Marsh demonstration garden

2011-06-13T09:30:00.001-07:00

Fairyduster and Shaw's agave.

Aster, Nasella, Eriogonum, Salvia, Toyon.

- Posted at great expense from my iPhone

Creek Watch app

2011-06-09T19:33:00.001-07:00

A fresh update of the Creek Watch app reminded me that I ought to actually use it, so tonight I took a stroll along the Dominguez Channel and made a few reports.

From the friendly app:
"Creek Watch enables you to help monitor your watershed. Creeks and streams are a vital part of watersheds; they provide water to drink and sustain plant and animal life. However, they can also be a pathway for pollution to spread, and they are often too numerous for water boards to monitor without help.

Creek Watch provides an easy way to lend a hand by reporting on any waterway you pass. We then aggregate reports and share them with water control boards to help them track pollution,
manage water resources, and plan environmental programs.

Creek Watch is an IBM Smarter Planet Project developed by IBM Research-Almaden. To learn more visit http://www.creekwatch.org."

- Posted at great expense from my iPhone

Looking forward to the Lair

2011-05-27T13:54:00.000-07:00

I'm packing today - the house and for our Lair of the Bear vacation. The blog may go into brief hiatus depending upon how much fun I'm having doing other things.

See also Cannonical list of things to bring to the Lair

0.52" Rain; season total 17.99"

2011-05-19T09:48:00.001-07:00

0.28" of rain on 16 May
0.24" of rain on 17 May

For a total of 0.52". This is a large amount of rain for May in southern California and it fell gently over two nights, soaking in almost completely - ideal for gardens.

- Posted at great expense from my iPhone

Rain 0.05"; season total 17.47"

2011-05-15T18:52:00.000-07:00

A surprise shower hit overnight and we got 0.05" in 90250. Only 0.01" was recorded in the San Pedro annex. The timing of this rainfall isn't so surprising - we often get little showers into late May. However, I have yet to record significant rainfall in June, so this is definitely near the end.

Local garden tour

2011-05-12T11:11:00.000-07:00

I just discovered this in my email. It sounds like fun. There ought to be plenty of native plants, but also many Mediterranean plants on this tour.

South Bay Water-Wise Garden Tour

This Sunday, May 15, 2011
10:00 am to 5:00 pm

This is the first year of this tour, organized by Peggy Kramer, an OFG Workday attendee and whose sister leads a garden tour in the Oakland, CA area. 2 of the nine gardens shown this year are Ocean Friendly Gardens:

- Torrance area: This one was the site of a Hands-On Workshop (HOW) on Site Evaluation, sponsored by the City of Torrance. Then South Bay-Surfrider OFG Committee returned on Thanksgiving to join the owners, their family and OFG class participants to help build the garden. Now they just need an OFG yard sign!
- Gardena area: The owners attended an OFG Class and realized they already had an OFG and applied for a sign.

Check out the tour website.

Twisted and tied

2011-05-10T20:54:00.001-07:00

While looking at houses the other day I saw an interesting arbor structure made of primitively bent, twisted, and tied copper tubing.

There's a small electric light at the top:

There's no overall shot. I think that I tried, but it didn't come across well and I discarded the photo.

- Posted at great expense from my iPhone

Rain 0.01"; season total 17.42"

2011-05-10T18:01:00.000-07:00

A surprise shower hit last night bringing our rainfall total to 17.42". Here's what the rainfall looked like in my back yard for the past several years.

As you can see, this year was second overall in rainfall total for the years that I have tracked, but still only about 2/3rds of the largest rainfall in 2004-05. This is an illustrative data set since it captures the full range of rainfall that California tends to get. It also illustrates the frequently recurring or maybe constant drought theme in our state - only in years of greater than average rainfall (and snowpack) do we have a real surfeit of water given the public appetite.

Largest poppy ever?

2011-05-08T00:20:00.001-07:00

The largest I've seen. The flowers here are from only one plant of our native poppy. It's the coastal variety which has a yellower color than the safety orange of the interior variety. The flowers have lasted an extremely long time on this plant too.

This one is planted near the coast on a hillside, so perhaps it's in an ideal habitat. Shown below, it sprawls over a couple nearby rose bushes and an iris.

- Posted at great expense from my iPhone

First Matilija blooms

2011-05-08T00:01:00.001-07:00

They are growing on shorter stalks this year than last and there appears to be some rust on many of the leaves. Perhaps this is due to our wet winter.

Two days ago there was one. Today there were five or so blooms.

- Posted at great expense from my iPhone

More garden blooms

2011-05-03T08:05:00.001-07:00

More allium unifolium (foreground) and penstemon 'Margarita BOP'. Assorted Gilia capitata.

Tritelia about to bloom

A CA native, but not locally native.

- Posted at great expense from my iPhone

Is Devon Skies Blue-eyed Grass native?

2011-04-30T13:16:00.000-07:00

Maybe. Probably not.

That's completely unhelpful, so I'll try to elaborate. I'm not a plant professional, so I'll welcome corrections.

Right off the bat, the 'Devon Skies' part of the name indicates a selection or hybrid.

A little Googleing says that Blue-eyed grass 'Devon Skies' is in the genus Sisyrinchium, which is promising since many species of Sysyrinchium are native to western states. All are new world, but Sisyrinchium from midwest states or the east are not unheard of. I wasn't able to find a species name, suggesting that it's a hybrid. If I'd found something like "Sysrinchium bellum 'Devon Skies'" then the bellum part of the name would indicate a species native to California and I'd know this was a native plant selection.

A little more Googleing finds this blurb on Plantlust.com

"Super in the rock garden or front of the border. (It's sterile too!) We just learned that S. 'Devon Skies' was found in Edmund and Rita Heaton's UK garden (the National Collection Holders for Sisyrinchium)." Ahh. So that's why it's Devon Skies and not Lake County Skies.

This all suggests that its parents are not known and in a Sisyrinchium collection of national significance I would think the parents could be from anywhere. So that's why I say maybe. But the real answer is probably not.

If you really want a native, I'd buy one of the species known to be California natives. There's many, though in my neck of the woods the optimum time to plant and grow these has passed for this year. Sisyrinchium bellum (blue eyed grass, western blue eyed grass) is widespread in California, so it's probably native near you. There are dwarf selections if you like cute and compact: my girlfriend picked up one that's fantastically florific right now. I think it was Sisyrinchium bellum 'Fort Bragg'.

From a question on my native plant list.

Garden blooms

2011-04-29T00:56:00.001-07:00

Onion, gilia, penstemon

Pch iris

More pch iris

Douglas Meadowfoam. Limnanthes

Limnanthes isn't as big as it appears in the previous picture. See below. Massed as it was earlier in the season and elsewhere in the garden it looks quite nice. I like the frog, a find at Tuesday Morning, I think.

Checkerbloom or checkermallow. Sidalcea or some such from memory. I've always thought that this is sort of a garden underdog perhaps because it is a bit fragile and easily overwhelmed by plants around it.

- Posted at great expense from my iPhone

Margaret's mallow update

2011-04-26T17:05:00.000-07:00

My friend Margaret writes,
After we had the heavy rains in December, my mallow just seemed to stop thriving. This photo was taken today. Note that this year the seedlings started growing.
Part one of my pruning is evident in the photo. Part two will occur after the trash is picked up. I do hope my mallow can make a comeback.
I have collected the seeds from the cut branches.

I wrote back,

You have really well-draining soil, if I recall correctly. However, you may want to transplant a seedling or two to a slight mound that will provide better water shedding from the trunk in case that is the problem.

If you follow the label link to Margaret's mallow you'll see that this was an early 2009 transplant from a 1 gallon pot, so it's had a two+ year run. Maybe that's all you get from Lavatera assurgentiflora. The main native plant web sites that I surveyed didn't call out a specific life expectancy, but this web site says that it is short-lived:

http://www.gardenguides.com/taxonomy/island-mallow-lavatera-assurgentiflora/

so perhaps it's run its course.

Back to my blog vacation. See ya.

Bee road?

2011-04-14T22:14:00.000-07:00

An astute observer on my native plant garden list suggests that this is a concept useful in the U.S.

'Bee road' plans to save key pollinators

Co-operative's Plan Bee scheme will set up corridors of wildflowers as a food-rich habitat for honeybees, hoverflies, butterflies and moths.

Back to my blog vacation.

Rain 0.03"; season total 17.41"

2011-04-11T20:15:00.001-07:00

0.03" on 7 April

- Posted at great expense from my iPhone

Before and After

2011-04-07T18:00:00.000-07:00

It's for sale now and I doubt it will ever look better. Let's see how I started and how I ended up.

Before

In between

After

Before

After (same area shown at right with French door)

End of March blooms

2011-04-05T01:27:00.001-07:00

I'm still taking a break but these were too easy to pass up.
I liked the structure of this Phacelia tenacetifolia much better the night before when the background wasn't so distracting.

Its flower:

Bay and Douglas's Meadowfoam. There's a single Meadowfoam in the Tenacetifolia pot if you look carefully.

Ceanothus and Western Redbud.

Heuchera 'Wendy'

- Posted at great expense from my iPhone

Away for a while

2011-03-30T09:05:00.000-07:00

I'm going to a take a brief blog vacation. I'll be back soon.

Rain 0.44"; season total 17.38"

2011-03-27T09:22:00.001-07:00

0.38" in the morning of 24 March.
0.01" got the ground wet on 25 March
0.05" recorded on 26 March in the AM.

When reading my rain gauge I've discovered that I have a higher (and, I believe, more accurate) reading if I fling the rain gauge around in a semicircle, driving water droplets that are on the sides of the gauge into the bottom by centrifugal force.* There can be a few 1/100 ths difference in readings before vs after using this technique.

I had previously used a technique where I moved the gauge slowly about such that the main body of water flowed up the sides and captured rogue droplets stuck on the sides with surface tension.

I'm certain that had I looked I would have found this rain gauge pitfall described elsewhere. But what fun would that be.

*centrifugal force from the point of view of a droplet. But of course if I were a strict adherent to classical physics I would say that I see a centripetal force on the droplets.

Rain 0.5"; season total 16.94"

2011-03-24T07:39:00.001-07:00

0.5" on 23 March

- Posted at great expense from my iPhone

Rain 0.28"; season total 16.44"

2011-03-21T23:52:00.001-07:00

That 0.28" happened to fall when I needed to make a long walk to my car. That was without an umbrella since I made the decision this morning that blue skies in the am meant blue skies all day. By afternoon the sun was shining like it had never rained.

- Posted at great expense from my iPhone

Rain 2.48"; season total 16.16"

2011-03-21T06:57:00.001-07:00

We're having a high rainfall year officially now. With some more storms coming through later this week we'll soon be into the high teens of inches for the year.

2.48" total for this storm with
2.20" measured at 6 pm on the 20th and
0.28" measured on the morning of the 21st with clear skies ahead for the day.

Update: Based on blue skies this AM I didn't take an umbrella and got caught in a downpour today, so there will be another blog post later on. Rain is expected about every other day this week and we already have the second highest rainfall in the past seven years that I've tracked in my back yard. The gray dashed line in the graph below is this year's rainfall. Only the seriously large rainfall of 2004-05 exceeds it.

- Posted at great expense from my iPhone

Back yard

2011-03-18T16:00:00.001-07:00

I figured that "Amanda" would have a mustache, but was pleasantly surprised that she was an actual female. Craigslist had come through for me and Amanda arrived with her boyfriend to take my pile of unused bricks away.

The bricks were one of the last tasks needed to clean up the yard.

Click for what I hope is a nice panoramic view.

- Posted at great expense from my iPhone

Stars of the meadow

2011-03-16T13:07:00.000-07:00

Poppies are the stars of the meadow right now. There's Blue-eyed grass and Yarrow mixed in with a couple other things, but its the poppies that are taking the prizes right now. I'm adding supplemental water and hoping for one last storm to give me some additional punch with the blooms.

My only regret is that I wish I had not used the inland poppy variety.

Rain barrels schmain barrels

2011-03-14T17:39:00.000-07:00

Someone else has cottoned to the fact that rain barrels are a gyp. Though I've not previously heard of Owen Dell, he seems to be a well-respected enviro-writer who is "master of the craft: Landscape architect, educator, and author". Thanks to Emily Green (previous link) I became aware of some of his recent writing where he calls bullshit on the cult of the rain barrel, using the generally-higher-rainfall-than-Los Angeles area of Santa Barbara as his point of reference.

Of course my reader already knows that rain barrels don't get the job done due to my insightful series of articles on the cult of the rain barrel.

Go and read Owen's blog and skip to the part where he writes rain barrel suppliers for more information:

Hello,

I have a 7,500 square foot lot, and I use about 140,000 gallons of water per year for landscape irrigation. A single 60-gallon rain barrel will supply 0.00043 of my annual water needs, making it necessary for me to have 2,333 barrels to meet those needs. They will fill almost a quarter of an acre of land if placed side-by-side. My lot is only about .17 acres, and the house and garden take it all up. Do you have any suggestions? Thank you.

The responses are illuminating.

Rain 0.01"; season total 13.68"

2011-03-08T14:41:00.000-08:00

I had hoped for more rain. Perhaps I'll get some today. However, overnight we had barely enough to get my rain gauge wet so I'm call it 0.01".

0.01" - 07 Mar 2011

Invasive plants at Home Depot and Lowes?

2011-03-06T18:23:00.001-08:00

Hot on the heels of my find of Ceanothus 'Yankee Point' at Home Depot, I found this on Saturday at both Home Depot and Lowes.

Scotch broom (Cytisus scoparius) and French broom (Genista monspessulana) are scourges of the local back country and while I know there are supposed to be "non-invasive" types such as this one, I'm still dismayed every time I see it since I don't know what sort of testing these plants go through before being sold at Home Depot and its ilk.

This one is being sold as Genista (Cytisus) x spachiana (Sweet Broom) which is believed to be a cross between Genista canariensis and Genista stenopetala. It will cross again with the invasive French Broom, which is how we have the selection Cytisus 'Porlock'.

Researchers are puzzled why Broom is such an innocuous plant in its home ranges and so invasive here.

California native meadow rejuvenation

2011-03-06T16:05:00.001-08:00

Hot on the heels of my somewhat remorseful post about my meadow neglect is a post about meadow rejuvenation.

Weeds dug:

Mulch down:

I think that the Platonic ideal meadow doesn't have a mulch, but mine does now. It's simply too much work to contend with the weeds otherwise. I chose a shredded bark mulch because I thought it would decompose fast enough to mimic decomposition in an actual meadow while still keeping the weeds down. I also thought it would stay on the slight slopes that I've built and not roll or wash off.

I had the help of Saul and Juli who worked with me all day and we managed to weed and prune the whole front yard as well as other miscellaneous tasks.

- Posted at great expense from my iPhone

rain 0.20"; season total 13.67"

2011-03-03T21:29:00.000-08:00

We had a steady rainfall last night - something in excess of what I expected given the forecasts - and ended up with:

0.20" on 03 Mar 2011

This wet season looks to be the second highest amount of rainfall in the past 7 years.

California native meadow apology / apologia

2011-02-28T08:54:00.001-08:00

I owe some time and effort to my California meadow, which despite my neglect for a year or more, has come back to life with our recent rains, but it hasn't come back as it was originally envisioned or planned. It looks nice and green, but it's weed city.

This blog is both apology and apologia for my meadow, and a bit of a How-Not-To as well as a How-To for those considering a California native meadow of their own. Here's short time line of my learning process.

I started in December of 2006 or January of 2007 with an over-seeded (by a factor of 10 at least!) little patch next to the curb that I thought was ruined by the termite crew who trampled the seeds into the mud. The crew may actually have stimulated germination, and I grew a veritable jungle of wildflowers that first year. It was a visual and audible triumph with what must have been hundreds of bees buzzing into the mix of too too many flowers.

The original mix of nine(!) types of seed has had some winners and some losers:

1. Wild Heliotrope (Phacelia Tanacetifolia) - flourished in the meadow area for the first year. Afterwards spread to less competitive parts of the garden.
2. Goldfields (Lasthenia Californica) - I had a small patch the first year but these were overwhelmed by the taller flowers and I never saw them again.
3. Botta's Clarkia (Clarkia bottae) - never saw it.
4. Elegant Clarkia (Clarkia Unguiculata)- this grew nicely in the meadow and then spread to areas of the garden where it didn't have such competition.
5. Purple Needle Grass (Nasella Pulchra) - Didn't like the meadow area but flourishes beside it. I since read that if incorporating bunch grasses in a meadow, one should give the grasses a season head start to grow on their own before incorporating annuals.
5. Red Fescue (Festuca rubra molate) - This has been popping up in scattered locations for a while and making the whole thing look unplanned.
6. Globe Gilia (Gilia capitata capitata) - Vigorous grower, but it too now likes other parts of the garden with less competition.
7. Yarrow (Achilea millefolium) - Outgrew them all like the tortoise racing the hare. The root system and dense mat of yarrow kept out most wild flowers in subsequent years. It then died back and we've had a bit of a revival lately with mostly poppies among the yarrow.
8. California poppy (Escholsia of a couple varieties) - I didn't know enough to chose the coastal variety when I started so I have hybrids.
blue eyed grass (Sisyrinchium douglasii)- inhabits the occasional spot where it can wedge in.
9. Foothill California Fuchsia (wild selection - most likely Epilobium canum latifolium) - A surprise success. It keeps popping up at the edges of the meadow, but can't seem to establish itself firmly.

I should have planted just a few different types.

After the first crop of wildflowers had bloomed, I realized that the taller wildflowers had allowed the lower-growing yarrow to insinuate its roots into all corners of the meadow and I was left with an almost monoculture yarrow "lawn" for the remainder of that year.

I thought it was pretty cool, but I allowed the yarrow to flower and get dried out and rangy looking and a year later it wasn't quite so cool. The lesson here is that since I have a suburban yard and garden, not an actual meadow in the wilds, it ought to look a bit more groomed which means mowed or string-cut every so often and irrigated enough to stay greenish. Plenty of people maintain mowed yarrow "lawns", so this isn't unreasonable.

The profuse wildflower bloom was never repeated, but the flowers have mostly managed to hang on in other parts of the front garden, so I haven't lost all annual wildflowers. I since learned that botanic gardens that maintain meadows actually work really hard to maintain the meadow aspects and even go so far as to solar-sterilize the soil every few years to keep the invasive weeds down. They also sow seed in defined drifts as opposed to my method of all mixed together - a good garden design guideline. They would also NEVER sow nine varieties in a spot this small. I ought to have started with two or three well-chosen varieties - maybe yarrow transplanted from a flat in order to space it out and control it more, the coastal variety of poppies, and one other.

In 2009 I took "drought tolerant" at face value, perhaps because I was feeling ambivalent about the whole thing, and the yarrow all but withered away so that by the end of last summer the whole meadow was looking pretty desolate and weedy. I had sprinklers, but I chose not to use them. I wasn't feeling good about my yard. When the yarrow dies back, the wind brought weed seeds to my yard which have infested the meadow area. Maybe some well meaning saboteur even scattered weed^H^H^H^Hgrass seed to help me out.

This brings us up to winter 2010-2011. Enough yarrow survived that with this winter's rain it's come back somewhat - but not to the monocultural levels that it previously was at. In the mean time, poppies have "popped" up in profusion among the weeds, perhaps because I scattered some more seed at some point. It turns out that the two dominant native plants still surviving are the same as a"lawn" mixture that Larner Seeds is selling.

NEW
The Grassless Lawn Combo

For light lawn use, strolling not soccer, we have had good success on the coast with a combination of Achillea millefolium, yarrow, and Eschscholzia californica var. californica, the coastal poppy. These two tough and vigorous perennials can be mowed for a lawnlike effect or left to flower for a flowery meadow. Drought-tolerant on the coast once established, it needs occasional water inland. Seeding rates: 12-15# per acre, 1# per 800 sq. ft., and one ounce sows approximately 50 square feet.

So I'm going to go with it. I have a 12 year old who can learn the art of weed pulling and we'll pull all those grassy weeds, put down some fine mulch to prevent more weeds, and let the yarrow and poppies duke it out.

0.86" rain; season total 13.47"

2011-02-27T10:51:00.001-08:00

0.85" rain overnight ending in the early AM on 26 Feb.
0.01" hail and rain that fell briefly in the PM.

- Posted at great expense from my iPhone

Juli made me do it

2011-02-25T20:01:00.001-08:00

As of last weekend, I have a little brick and concrete paver patio in the back.

- Posted at great expense from my iPhone

Rain 0.20"; season total 12.61"

2011-02-20T20:03:00.000-08:00

0.20" on 20 Feb

The San Pedro annex recorded 0.30" for the whole storm, about half of what recorded.

- Posted at great expense from my iPhone

Native plants at Home Depot

2011-02-19T19:38:00.001-08:00

Juli and I were at Home Depot today. She first asked about Narcissus.
J: Do you work in the garden center? Ok. Do you have any Narcissus?
Slackjaw: Nasisus?
J: No, Narcissus.
S: Narsis? I've never heard of it. Turns to mouthbreather: How about you?
M: blank look and shrug

The conversation continued just as futilely but I wandered off. We were about to go to Anderson's in frustration, since at least the nursery staff are conversant with common exotic plants when we remembered that our pocketbooks prefer Home Despot.

We decided on Leptospermum scoparium "Crimson Glory" ( Crimson Glory Tea Tree ) that Juli wanted after finding the particulars of the three different selections offered on our smart phones.

Right next to the Leptospermum were 20 or more Ceanothus "Yankee Point" favorably priced at 5.98 for a 1 gal! Hmm what's this California native plant doing at HD?

Should I be looking for signs of the apocalypse or what?

We took a last crack at Narcissus with another nursery staff member who at least knew where the bulbs were located, but failed, and left.

- Posted at great expense from my iPhone

Location:Torrance Crossroads

Rain 0.48"; season total 12.41"

2011-02-19T19:10:00.001-08:00

19 Feb 0.45" in the am
19 Feb 0.03" by the pm

It's still raining, but we have yet to get anywhere near the 3" forecast for this storm.

- Posted at great expense from my iPhone

Rain 0.26"; season total 11.93"

2011-02-16T19:01:00.001-08:00

0.04" on 15 Feb
0.22" on 16 Feb

A couple more days of rain are in the forecast, including one report I heard today of 3" of rain in coastal areas.

- Posted at great expense from my iPhone

Lupines persist in industrial park

2011-02-14T13:40:00.001-08:00

An undeveloped area that I pass on a regular basis is slated for use as a large industrial and commercial park. This year and last I've noticed these nice lupines that persist in the weeds of the graded and waiting land. I believe that they were turned up from the native seedbank when the land was last bulldozed. I wonder if someone ought to harvest their seed to preserve locally endemic genetic variation?

It was about 3 years ago that the fields were leveled by bulldozer and I imagine that the real estate crash has contributed to them lying fallow for the past two rainy seasons.

- Posted at great expense from my iPhone

Location:E Maple Ave,El Segundo,United States

Grow Native Nursery in Westwood

2011-02-11T10:54:00.000-08:00

I visited the Grow Native nursery in Westwood last weekend on Superbowl Sunday. It was only a short jaunt up the freeway - the closest of any solely native plant nursery to me It's been open only since late last year and I hadn't had an earlier chance to visit because I've focused on home improvement tasks (which I decided were mostly not interesting enough to blog about since I was hiring others for the big stuff).

A partnership between Rancho Santa Ana Botanic Garden and VA Greater Los Angeles Health Care System, helps train veterans on the propagation, care and maintenance of California native plants and offers beautiful plants for sale to the public. A weekly farmers and artisan market is held every Thursday from 12 to 6 p.m. RSABG members receive 10 percent discount on all purchases from the Grow Native Nursery booth at the market and at the nursery.

Juli wanted some of the coastal variety of California Poppies for her yard and some other native plants. Since I wouldn't ever discourage her from planting natives, off we went. They had a reasonable selection and we ended up with:

Wind Poppy (Stylomecon heterophylla) x2 pkts of seed. These are marvelous flowers that I hadn't even known of two years ago. Search on Google Images or see this or this.

Maritime Cal. Poppy (Eschscholzia californica maritima)- The coastal variety has yellow centers instead of the solid orange of the inland variety (in 1 gal pots x2)

A dwarf selection of blue eyed grass (Sisyrinchium bellum
probably ‘Rocky Point’) to go with a dwarf selection that she already had - based on growth habit they are the same selection but memory fails as to the correct selection. x2

A 1 gal Ribes speciosum (Fuschi-Flowering Gooseberry) a plant with wicked thorns that will be an impediment to prowlers at the bottom of her yard.

When purchasing, I was asked if I was a member of Rancho Santa Ana Botanic Gardens and when I responded that I was not, and regretted that I'd never visited, we received two complimentary tickets for admission.

I will have the pleasure of planting all these some time this weekend in the San Pedro garden annex.

The all new house

2011-02-01T20:21:00.001-08:00

Freshly painted trim (Evan's Painting in San Pedro) and new green stucco (Jeff Graham Plastering in Torrance). Red door using Benjamin Moore Country Red was either my mother's or Juli's insistence, though I had done the work of picking the exact color in an earlier iteration of this color scheme. This proves that I do take advice, despite claims to the contrary.

The meadow and most of the native plants are highly unkempt, which explains why I haven't posted about them in a long while. I may have a longer native plant mea culpa later. For the moment the Aristida purpurea in the second photo is about as kempt as the natives get.

- Posted at great expense from my iPhone

Rain 0.06"; season total 11.67"

2011-01-30T17:19:00.001-08:00

Good things are happening. The neighbors with the noisy dog moved out. The trim on the house has been painted a nice color. The painters finished a couple days ago. And we had 0.06" of rain today.

- Posted at great expense from my iPhone

Cercis and Ribes sitting in a tree...

2011-01-30T09:41:00.001-08:00

Many of California's native plants are coming into their best season now. In my back yard I have Cercis occidentalis (Western Redbud - a wonderful small tree) and Ribes aureum (Golden currant) planted next to one another. I intended the Ribes to be in bloom when the Redbud was not, but here they are working together. I think they both could use a bit more sun, but they have done pretty well in this spot for a few years now.

- Posted at great expense from my iPhone

Griffith Park hikes

2011-01-24T18:04:00.000-08:00

Until a couple weeks ago I'd never hiked Griffith Park, despite the fact that it is only a 30 minute (in the AM when traffic is low) drive to many trail heads and contains an abundance of local flora and fauna. The official narrative on Griffith Park says,

With over 4,210 acres of both natural chapparal-covered terrain and landscaped parkland and picnic areas, Griffith Park is the largest municipal park with urban wilderness area in the United States. Situated in the eastern Santa Monica Mountain range, the Park’s elevations range from 384 to 1,625 feet above see level. With an arid climate, the Park’s plant communities vary from coastal sage scrub, oak and walnut woodlands to riparian vegetation with trees in the Park’s deep canyons. The California native plants represented in Griffith Park include the California species of oak, walnut, lilac, mountain mahagony, sages, toyon, and sumac. Present, in small quantities, are the threatened species of manzanita and berberis.

Over the years recreational attractions have been developed throughout the Park, however an amazingly large portion of the Park remains virtually unchanged from the days Native American villages occupied the area's lower slopes.

All that appears to be true.

I had a plan to lead Boy Scout Troop 283 on a hike to the Hollywood sign but since I'd never been there I pre-hiked the trail with my buddy Dan. Dan and I had ideal hiking weather: cool and overcast. The following weekend I hiked the trail again with the Scouts, but the weather was warmer and I needed all the water that I brought with me. Dan was also seized by enthusiasm for Griffith Park and met the Scouts on the trail while he completed a much longer Griffith Observatory to Mt. Lee hike. Modern Hiker has a particularly nice writeup on the Hollywood sign hike that I followed both times.

View of the transmitter tower on the top of Mt. Lee, home of the Holylwood sign. The edge of the sign is barely visible in this photo, I think, below and left of the tower.

We're getting closer.

The trail is dirt access road and paved road on the upper reaches of Mt. Lee. It twists and turns through the canyons.

There! A fence separates you from the sign. It's pretty steep, so the public safety aspects of the fence seems legit.

Dan on top of nearby Mt. Cahuenga looking out to the San Fernando Valley ("The Valley" in local parlance).

I'm using high dynamic range photography whenever I can these days, as you can see below.

Surveyer's mark on Mt. Cahuenga.

Fun single track trail up Mt. Cahuenga.

Native plants grow in profusion.

Scouts on the way up.

Nice view!

On the second descent, view of Mt. Lee though sycamores.

View down to the trail below.

I'm sure I'll be back to hike some other trails soon.

Farm, Garden, Landscape

2011-01-19T18:00:00.000-08:00

It was Pomona who put me on to Google Ngrams - word frequency analysis based on the digitized library of Google books. Here's an Ngram for the words Farm, Garden, and Landscape.

Are we several years into a new agrarianism?

I've been Wordled

2011-01-14T13:46:00.000-08:00

words, beautiful words

Blog action - save Arcadia Woodlands

2011-01-07T12:13:00.000-08:00

I'm copying the following text from Wild Surburbia and urging everyone to sign the petition to save a local natural resource. Other blogs, linked below, have far better background than I so I urge you to visit them, read about the issue, and get involved.

In solidarity with other bloggers, I implore all of you to sign the petition to save Arcadia Woodland, contact your County Supervisor, make yourself heard. Because as the Once-ler said:

"Now that your're here,
the word of the Lorax seems perfectly clear,
UNLESS someone like you
cares a whole aweful lot,
nothing is going to get better.
It's not.

Update: There are now many more blogs that have posted to raise awareness of the Arcadia Woodlands

Fellow bloggers in solidarity to SAVE THE ARCADIA WOODLANDS:

Pasadena Real Estate Blog with Brigham Yen

Chance of Rain
Echo Landscape Design

L.A. Ecovillage Gardener's Weblog

Pasadena Adjacent

Pasadena Daily Photo

Slow Water Movement

Temple City Daily Photo

The Sky is Big in Pasadena

Weeding Wild Suburbia

While we're talking about rain

2011-01-07T12:04:00.000-08:00

I've noticed that many of my recent posts are simply cataloging rainfall. That's an appropriate activity for a garden journal type of blog, but just how accurate and useful are my figures?

I now have six years of data to compare against a generic, but official, "Los Angeles" rainfall and I'm happy to report that my measurements correlate well with the official Los Angeles measurements. See below how there's a straight line relationship between my measurements and the official ones? I take that as a good sign. I think that the offset in the official measurement is due to their better sensitivity to heavy fog / light rain. For instance, yesterday it rained enough to wet the concrete at my house, but not enough to measure. I will bet they have more sensitive measurements at the official Los Angeles weather station.

Just how useful my rainfall figures are is debatable. Certainly, I put them to good use in my rain barrel series, a stunningly insightful bit of analysis that made blindingly obvious the merely "quite clear" . For the conspiracy theorists among us, I've also independently correlated official government rainfall reports, so at least we know they're less likely to be lying about the rain. Now about that moon landing.... However, for me the greatest usefulness is the satisfaction that I get as a citizen scientist. I suppose I ought to aspire to sounding rockets or weather balloons or at least a higher degree of automation. Maybe later.

Rain 0.61"; season total 11.61"

2011-01-04T20:17:00.000-08:00

0.61" on 3 Jan.

(versus 0.5" reported at the San Pedro annex where we've now added to our rain gauge reporters.)

We're even with the rainfall amount that we had at this point during the very wet 2004-'05 rainy season. That season brought me about 29" total.

- Posted at great expense from my iPhone

Christmas Holly 101 and Living Wild

2011-01-01T22:39:00.000-08:00

...are the names of two web sites that I'm looking at right now.

Christmas Holly is one of the common names for Heteromeles arbutifolia, also known as Toyon. It's a native shrub that has distinctive red berries and it's said to have been the "holly" in Hollywood.

Christmas Holly 101

Living Wild is a wiki that focuses on food, medicine, and landscape plants native to the Sierra.

Living Wild

Thanks to the Gardening with Natives email list for the links.

Rain 0.7"; season total 11.00"

2010-12-29T23:11:00.000-08:00

After last week's series of storms, we have more rain for this time in the season, than in any rainy season in the prior 6 years.

In the two watches department: On Facebook, my neighbors noted that they had about 8" of rain for the last series of storms versus my 7.14" (which I borrowed from SpaceX, only a mile or so up the road since my gauge overflowed while I was away). I guess I'll have to just note that there's some uncertainty there, unless I can find a closer weather site to break the disagreement. What's this have to do with two watches? I've said for years that only the man with two watches doesn't know what time it is.

Rain 0.66"; season total 10.30"

2010-12-26T08:48:00.000-08:00

In normal circumstances, this would be a significant rainfall, but given last week's performance by Mother Nature, it seems mundane.

- Posted at great expense from my iPhone

Rain 7.14"; season total 9.64"

2010-12-24T23:45:00.000-08:00

15 Dec, 2010 0.01" overnight
16 Dec, 2010 through Dec 24th, 2010, estimated over 7 inches!

I was away from the house and my poor rain gauge maxes out at 5.5". That max is somewhat below the upper lip and the gauge seems to have overflowed, so I'm estimating 7" or more in my back yard. That's a phenomenal amount of rain for California. I won't belabor that point, since it's already been all over the news.

Rainfall amounts at nearby SpaceX, just up the road, were:
15 Dec 0.01" (agrees with me, good)
16 Dec 0.02"
17 Dec 0.44"
18 Dec 1.15"
19 Dec 2.09"
20 Dec 1.28"
21 Dec 0.87"
22 Dec 1.27"
23 Dec 0.01"
24 Dec 0.00"

For a total of 7.14", in good enough agreement with my estimate. On top of the 2.50" of rain that we'd had already (a normal year by recent standards) this makes 9.64" for the season.

Fortunately, the house had no obvious signs of water damage, so I'm counting myself lucky and prepared: I had my downspout diverters up and had confidence that my garden could absorb quite a bit of water. Still, I would have liked to be here.

Rain ???, season total ???

2010-12-19T21:54:00.000-08:00

It's been raining cats and dogs, possibly the most exciting storm this year, but I have no update until I return home. See my other blog for some cool pics in the mean time.

- Posted at great expense from my iPhone

Let's play Global Warming

2010-12-15T20:55:00.000-08:00

Found in a store today.

I used OCR on the back side of the package:

Global warming -— the steady
increase in Earth’s air and ocean temperatures since the mid-20th century - is one ofthe most discussed and studied topics in the scientific community today. This kit introduces you to Earth': climate and the issue of global warming with 23 hands-on experiments. Since Earth's formation, its
climate has been constantly changing. Periods ol warmer climate have alternated with ice ages. These changes happen over long periods of time. During the last few decades, a warming in the climate has been
observed everywhere on Earth. While some warming may be due to natural phenomena, scientists predominantly attribute global warming to human influence. This kit gives you the basic knowledge you need to understand the chmate, wlry it changes, and how our actions affect it.

First, learn about Earth's climate
system, weather, and atmosphere by conducting experiments with a model
Earth and atmosphere. Explore the hydrological cycle to learn about humidity, clouds, and precipitation. Model Earth’s heat reservoirs, thermals, global and local winds, and ocean currents.

Next, learn how human activity
influences the climate with experiments involving carbon dioxide and the greenhouse effect. Measure the effects that increased levels of carbon
dioxide have on air temperature.
Finally, investigate the potential
consequences of global warming on humans, ecosystems, and the world's economies. Learn what we can do to protect the climate.

Rain 0.24"; season total 2.50"

2010-12-06T10:37:00.001-08:00

0.24" of rain fell overnight for a season total of 2.50" so far.

Anticipating a dry winter and knowing that my natives will look best later with more water now, I was out watering some of them by hand this am, before the clouds had all burned off.

- Posted at great expense from my iPhone

Worldwide cost of tap water

2010-11-29T18:39:00.000-08:00

Water is too cheap!

A little further down in the blog when I conclude that rain barrels are only the leading edge of a water public relations campaign and that they only make sense if they are given away free, I made a casual comment that water is cheap. "Tap water costs next to nothing" is the exact quote from my most recent Rain barrel vs. soil rant. A comment from Diane of Food, Fun and Life in the Charente was that tap water was too expensive to see extensive outdoor use in France and the UK.

Wikipedia supports this, citing 6% of total residential water used outdoors (lawn watering and washing cars) in France. This is much lower than California (The Metropolitan Water District of Southern California estimates that, "in hot, dry areas, landscape irrigation can account for as much as 70 percent of the summer water use in single-family homes." This is probably a histrionic upper limit for PR purposes, but it can still serve as a point of comparison: 6% is a factor of 10 less than 70% so the real numbers are probably not in alignment either.) But is it really a cost issue that keeps outdoor water use in France much lower than in southern California or is it a cultural and horticultural issue?

A little Googling turned up a survey of U.S. water prices at Circle of Blue from earlier this year. It's an interesting read. Such surveys are complicated to synthesize data for because in addition to water use costs, there can be meter charges and other fixed monthly or bimonthly charges as well as water disposal costs (sewer fees) that are based on use. In response to a query, the author responded that sewer costs were not addressed in his article. I assume that it included the other fixed costs of water service.

I computed averages for California cities listed in the article and compared them to four European nations (I actually computed two California averages: one for Fresno, San Jose, San Francisco, Los Angeles, and San Diego and a second that excluded San Francisco because it has such a high urban population density and high rainfall that it is markedly different in water use pattern.)

Data for average residential prices for water in four industrialized European nations is contained a 2006 report titled "VEWA Survey Comparison of European Water and Wastewater Prices" that I found online. These numbers do not include sewer charges, so ignoring the several year difference in freshness of the data, it's fair to make the comparison directly to Circle of Blue numbers. More Googling turned up average rainfall on a per region or per country basis. Those are very rough numbers, since within Great Britain, for example, rainfall averages can vary between 65 and 447 cm. Nonetheless, comparison of California vs. European water rates and annual precipitation is interesting.

Diane was right - costs are higher in industrialized Europe. Not only that, but we also have much scarcer precipitation in California, and we still charge less, whereas one might intuit that we would charge more for a scarce commodity. The flip side of average costs is average use. I didn't tabulate water use numbers, but it's 125 gallons per day for the five California cities in the average and 159 gallons per day excluding San Francisco. European water use might be well below half of ours, given France's 6% use rate cited for outdoor water use versus our much larger average. However, they would have to supplement normal rainfall much less on average to maintain a green lawn since they get more rain in the first place.

Would nearly a factor of two increase in water price result in Euro-style water usage patterns in California? Maybe. This data won't lead us to a definitive answer, but people are funny about prices - consider gas prices changing from 2.50/gallon to 3.50/gallon and remember how many people it drove to better fuel economy cars.

A better comparison would be water costs and patterns of use between coastal southern California cities and other Mediterranean climate cites.

Rain 0.05"; season total 2.26"

2010-11-28T20:36:00.001-08:00

0.05" fell while I was in Joshua Tree last night. While we endured blasts of frigid air the coast was enjoying a light sprinkle.

- Posted at great expense from my iPhone

Rain 0.08"; season total 2.21"

2010-11-24T08:05:00.000-08:00

0.08" of rain on 24 Nov 2010

Rain 0.09"; season total 2.13"

2010-11-21T23:06:00.000-08:00

Forecast was for 0.5" and thunderstorms. Not so much.

0.05" of rain on Nov 20
0.04" of rain on Nov 21

- Posted at great expense from my iPhone

Rain barrel vs. soil

2010-11-15T18:11:00.000-08:00

You are a rain barrel stud, but you're beginning to feel a slight unease. Your sense of equanimity is a little disturbed because you've been reading this blog. You figured out that tap water costs next to nothing, so the $500 you spent on rain barrels is beginning to chafe in your tender areas - not only is there no benefit during the majority of the year when we have no rain in our Mediterranean climate, but the barrels aren't the most aesthetic or space-efficient addition to your yard. You want to do the right thing for the environment and a casual survey of your yard during the last rain storm suggested that next to the quantity of rain running off your driveway and out to the street, your rain barrels were looking a little...paltry.

Many homeowners in suburbia already have an aesthetic* and affordable solution to keep rainwater on their property without the use of rain barrels or even new and exciting green ideas like planting with California native plants. It's called lawn. Though fast falling from fashion in many circles, your lawn is a great way to keep water on your property. This is a slightly heretical thought among the green crowd, but for most homeowners in southern California today, their lawn is the best choice to keep water on their property. This is a pragmatic observation based on our collective infatuation with lawn, our unwillingness to give it up, and the fact that it may take up the majority of a home's landscape. If you're offended by the idea of a lawn doing something useful, then just assume I misspelled garden as you read along.**

The bottom line is that whether you have a lawn or not, the same basic principles apply and they revolve around knowing your soil and keeping it healthy, because healthy soil infiltrates water and stores it for future use far more effectively than rain barrels. How much more effectively? I'm glad you asked. For detailed information I refer you back to my previous post called Soils primer, which I will quote here.

Suppose you have a lawn that's 40 feet x 15 feet. This is a modest sized area but it is also a convenient 600 square feet. A previous post shows that 0.15" of rain falling on 600 sq ft of roof will exactly fill a 55 gallon rain barrel, so we're making an apples to apples comparison of lawn versus rain barrel: If that 600 square foot lawn can store 0.15" of rain, then it will be doing as well as a rain barrel collecting water from a 600 square foot roof.

Since you've been reading this blog and following along at home, let's imagine that you've attended to your soil health by tilling it if compacted, adding 5% organic matter by weight to the first 12" and topping bare soil with a mulch. Don't worry about topping your lawn with mulch, the grass will act like one, with the added benefit that turf grass has a multitude of fine roots that help infiltrate water. Water retention and water availabilities will then go up by a factor of 1.37 and infiltration rate will go up by a factor of 3.0 from the minimum values indicated in the soil texture table below based on what I wrote in Soils primer. We'll be assuming these soil improvement / conditioning factors going forward.

(Remember that available water is the measure of water that plants have available to their roots, and the wilting point of the plants is when available water goes to zero. Total water is just that - all the water that can be stored, but a large part of that water is not accessible to plant roots.)

For the sake of argument, let's say we have a one foot depth of soil to work with. This might be close to true if your top foot of soil is well-conditioned, but you have compaction starting one foot down. However, for most people this will not be their case - their soil will drain their water table, at least by a tenuous connection. Engineers call these sorts of assumptions worst case bounding assumptions - meaning that you can expect your soils performance to be at least as good as that predicted using these bounding assumptions.

If you water your lawn during our dry season (many people do not) then you won't start with perfectly dry soil before a rainstorm: You'll start with some fraction of your available water since you will maintain your watering schedule up until the first rain so that your lawn does not wilt or brown. We'll choose a situation where 50% of available water has been depleted and is therefore available to refill in a rainstorm. At 50% available water in sandy, well-conditioned, soil you'll have 0.5*1.37*(1.2-0.9) = ~0.20 inches per foot of soil water remaining and ~0.20 inches per foot of soil water holding capacity. What was the amount of water I could hold in a ran barrel from a 600 square foot roof? Oh yeah, 0.15 inches. Certainly 0.20 inches is better than any old rain barrel! In fact it's 33% better in this example.

Under these assumptions the advantage to storing water in soil only gets better the more clay-like the soil becomes. However, the infiltration rate - the rate at which surface water can work its way into the soil - goes down dramatically as soil becomes more clay-like. If you have clay soil and the improvements noted above you can expect a worst case infiltration rate of 3*0.01 = 0.03" inches per hour. That's a low rate that will lead to runnoff. Many of our storms easily exceed that.*** So in the case of high rates of rainfall the rain barrel will be superior - at least until the first 0.15" has been captured. Nonetheless, if I had a choice to spend $500 on rain barrels**** or $500 on my lawn, the more effective and aesthetic expenditure would appear to be on the lawn, though you will have to maintain the soils condition.

Soils with low infiltration rates contribute to runoff more easily than those with higher infiltration rates and one way to mitigate that is to create a shallow depression or a berm that will trap runoff and prevent it from..running off. This modification can be part of your newly justifiable $500 lawn improvement program.

*aesthetic - remember, it's in the eye of the beholder.
**There's plenty of information on converting lawn to native plants out there already, so if he keeps reading our "rain barrel stud" may yet turn into a "naturals birder".

***rainfall rate - his is why we like slow steady rainfall on our fire-crisped hills: no mulch or growth makes infiltration even more difficult than usual.
****Susan Carpenter of the LA Times spent that much for two rain barrels and received a third for free from LA County.

Catalina Ironwood as street tree - before

2010-11-15T14:38:00.000-08:00

I was able to take a still out of a video that Margaret sent showing the green concrete that beautified the Aviation median strip before the Catalina Ironwoods were put in.

This view is looking the opposite direction as the picture in my previous blog post. Empty planter boxes surrounded by green-painted concrete were there for years.

Catalina Ironwood as street tree

2010-11-13T13:15:00.001-08:00

Over in Margaret's neighborhood the county recently put in new street landscaping with Catalina Ironwoods, deer grass, and a few other natives. Margaret had emailed me in May of 2009!! about a neighborhood vote to use the native plants. Although i think it was planned for 2009, apparently it took until now to put the native plants in.

Here is an bit from the May 2009, email from Margaret which shows the influence of a neighborhood association.

" Several weeks ago I attended the Del Aire Neighborhood Association meeting.
...it was discussed what will happen to the median strip at Aviation. The olive trees will be relocated to another Los Angeles city and in its place Catalina Ironwood trees will be planted. The Neighborhood Assoc. was adamant that only Calif. natives be planted. In fact they turned away a shipment of some east coast trees. The renovation is being headed up by Anne Kershner. Should start in the fall."

- Posted at great expense from my iPhone

Soils primer

2010-11-10T21:29:00.000-08:00

I was guilty, just like many of you. I went through the gardening motions of tilling, composting, cover cropping, and mulching without a good understanding of their real impact. I despise unthinking orthodoxy even if I believe it's correct, and I ought to have applied that philosophy closer to home. For all my belief in the value of soil improvement I could have been speaking cavemanese when it came to a real sophisticated rationale behind my belief: "Compost gud. Mulch gud. Make gud soil." It took me a while, but I've finally made sense of a number of soils issues that were flitting about the corners of my mind.

It turns out that there's a useful level of understanding for gardeners a step or two above the cavemanese or dummy level. While there's plenty of web information on the necessity of mulching and composting those articles are are often little better than my cavemanese since they don't provide a scientific or evidence-based rationale. I'll try to leave that sort of writing for the garden mulch sycophants, color-by-number recipe followers, and garden hangers-on and instead give you a little bit of an empirical soil science rationale behind the seven pillars of garden soil maintenance.

Were you aware that "loam" is just a word to describe a particular mixture of mineral particle sizes of your soil (soil texture)? I guess I read too many pioneer farmer stories in my youth, where they tilled the "rich loamy soil", and consequently I thought until recently that loam had copious amounts of organic material in it. It doesn't. Let me repeat more loudly: LOAM DOES NOT HAVE ORGANIC MATERIAL IN IT. Neither does clay. Nor does silt.

As it turns out I could be excused for misunderstanding loam, since in common usage, loam can mean that organic material is incorporated. For example, if one types "define: loam" in Google, the very first definition is from no less an authoritative source than Princeton, who state that loam is "a rich soil consisting of a mixture of sand and clay and decaying organic materials". Apparently Princeton is not quite the voice of authority in the garden, where we definitely do not include organic material in our understanding of soil texture.

Loam is a particular kind of soil texture described by a particular the ratio of sand, silt and clay. Sand, silt and clay are the mineral content of your soil. Sand, silt and clay are all mineral in makeup and are discriminated by size and shape. They also (generally speaking) do not absorb water. Rather, the water holding capacity of sand, silt or clay is due to the spaces between the soil particles. Scientists might call these the interstitial spaces. Sand is the largest size range from greater than 50 microns and up to 2mm. Silt is between 2 and 50 microns and clay is the smallest at 2 microns or less. 1 micron = 0.001 mm.

This hadn't really sunk in even when I blogged previously about my Ocean Friendly Garden class and threw up a graphic of a soil triangle (ternary phase diagram for soils), reproduced below.

Loam is about 40% sand, 40% silt, and 20% clay. Remember that there's only mineral constituents on this phase diagram -- no organic material. Since loam is on this phase diagram, loam can not have organic material in it. The nice thing about soil texture is that it is immutable: Whatever soil texture you have in your garden, it will always be the same during our lifetimes, unless you cart in new soil. Thus soil texture is the starting point for any garden soils analysis.

You can figure out your soil texture using the mayonnaise jar test. Knowing your soil texture is important because it will give you some guidelines about how quickly water can infiltrate the soil, how much can be retained for use by plants, and how quickly it will percolate out of your soil. You and I don't have to guess about what these various figures of merit are, since soil scientists have already done that work. Here's a table that I built as a summary of their prior work.

Total water, available water, and infiltration rate ranges based on soil texture alone. Good soil management practices will improve these figures.

Remember that the vast majority of water that is stored in soil is stored as either a surface film of moisture or in the space (interstices) between soil particles. In the table above, total water is all the water that soil can possibly store whereas available water is the part of total water that plants can access and use. Fine soil textures store more water per unit volume than coarse textures but are less able to release that water back to plants - they have a greater surface area and it's surfaces that hold on to water - water is easily drained from large voids. Also on the chart is infiltration rate - the rate that a given soil texture will take up water. Some of the entries for infiltration rate are blank because I didn't find that data in a convenient place on the web. The trend should be clear, however. Fine particle soils like clays are very slow to infiltrate and coarse particle soils like sand are very fast. An important take-away is that there's factors of about 2-3 differences in water storage and water availability but orders of magnitude (factors of 10) differences in infiltration rate based solely on the mineral content of your soil. These baseline figures can be altered based on your soils management.

A note on units: The units "inches of water per foot of soil" means that if I have a 1 foot depth of that soil type then I can store water equal to the given number of inches per unit area. For example, in sandy loam I can store 1.9 inches of water (per sq foot or per square meter or per square hectare) if the sandy loam soil goes to a depth of 1 foot. For two feet depth I can store 3.8 inches of water. I'm asserting this as if I'd invented the units, but really it's what I've puzzled out after finding lack of clarity on the web in the several places I looked. Nonetheless, I think I'm right.

Here in Los Angeles' South bay we tend to have either very sandy soil from ancient dunes or one of the clay soils from the marsh and wetlands that used to exist here. Depending upon how much fill soil you have, you could have both on your property as I do.

So far, we've been talking about the properties of sterile soil without organic material in it. Your soil undoubtedly has at least some organic matter and that increases total water, available water and infiltration rate. Better soil management practices can additionally increase those figures. For example, larger amounts of organic matter in the soil are also associated with high biological activity which is also associated with good soil health. A list of soil characteristics and practices that influence water retention and infiltration is provided below. The color coding indicates my assessment of degree of improvement.

Soil characteristics and practices that influence water retention and infiltration in soil.

I don't know that I'm hard and fast on all the color codes but what I do know is that there are measurable improvements for organic material and ground cover. In fact, the top seven items in that table could be considered useful, or possibly useful, to your soil. I might be accused of indulging in numerology if I made more of the fact that there are seven pillars of gardening just like there are seven pillars of Ismailism and that as I was going to St. Ives I met a man with seven wives.

Here's what the data says about mulching and soil organic content impact on water retention and infiltration:

Mulch increases water infiltration rate. From http://attra.ncat.org/attra-pub/drought.html.

Egads! tons per acre? Not to fear: Straw mulch applied at a rate of 1/2 to 3 tons of mulch per acre gives a depth of 1/2 to 1 inch according to this reference. Scientists use straw mulch because it's cheap and widely available, the depth is uniform and easily controlled, and because farmers would use it too. We'll make an engineering approximation that the convenient straw mulch cited above applies equally to all mulches and to all soil textures, which means that you could add about 1" of any mulch (leaves, bark, or whatever meets your aesthetic needs) to get a factor of ~2.5 increase in water infiltration rate. As a point of reference, native plant experts recommend 3" of mulch on bare soil, though their goals are also to provide weed abatement and reduce soil temperatures and water loss from evaporation. [SIDE NOTE: Why do mulches increase infiltration rate? Although I'm an empiricist for purposes of this article, I'll speculate that mulches prevent near surface compaction from rain, prevent migration of light soil components that could fill outer layer infiltration points, and provide an intimate "kissing" contact that reduces surface tension effects on water flow.]

Organic matter increases water retention. From http://attra.ncat.org/attra-pub/drought.html.

Now let's imagine that I till in 5% organic matter by weight into the top foot of my thin, compacted soil. Then not only have I relieved the soil compaction by tilling, but I also have the benefit of that 5% organic matter. I'll let the biology gradually return to feed on that 5% organic matter, provided I don't kill it by overfertilizing, over tilling, or one of the 'cides. According to the graph above, that 5% organic matter is good for about 37% more water retention. We might expect more improvement based on the biological activity and soil beneficial aggregation that will follow. Of course, you'll have to renew the organic material periodically as it degrades, but you should remind yourself that this activity that you're doing is called gardening, not "getting a massage while sipping a cold drink".

Suppose I also top the soil with 1 inch of bark mulch or grow a cover crop such as turf grass for a factor of ~2.5 increase in infiltration rate due to mulching effects. We know that the existence of roots will further improve infiltration rate, but I haven't found data on that. I also don't have data on the impact of beetles, earthworms and the like, nor on soil aggregation. Let's assume a 20% improvement in infiltration rate for these unknown factors - this is soil science not rocket science. What else do I need to do to maintain or improve soil health and therefore improve water infiltration and retention? One thing that I have to do is in areas where people or animals walk (turf grass, in particular) I'll need to periodically aerate to remediate compaction from walking.

The bottom line is that if I keep my soil healthy, then water retention and water availabilities could go up by a factor of 1.37 and infiltration rate could go up by a phenomenal factor of 2.5*1.20 = 3.0 from the values indicated in the soil texture table. Suppose you're not happy with only 37% increase in water retention. Then add more organics.

Hopefully you now feel like you're a leg up on the Dummies folk and have a better understanding of why we ought to add compost and mulch and why we build our soil's health by practicing good soil management. And who says there's no better living through science?

updated 9 Feb, 2011 to correct some typos and add a bit more clarity.

Sources around the web varied slightly in their exact numbers. I liked the good soil information on http://attra.ncat.org/attra-pub/drought.html, which I summarize here. I use a couple of their figures as well. I also used some other facts and figures http://turf.arizona.edu/tips1095.html.

Southern California vegetable garden

2010-11-09T12:59:00.000-08:00

Robert Smaus, the well-regarded but now retired LA Times gardening columnist, advised in early October, 2006 (http://www.latimes.com/features/la-hm-smaus5oct05,0,6059164.story) the following winter crops.

Winter vegetables

Many vegetables only grow, or grow best, during the cool fall, winter and early spring months. These include beet, bok choy, broccoli, Brussels sprouts, carrot, cauliflower, celery, endive, garlic, kale, kohlrabi, leek, head and leaf lettuce, mesclun mixes, onion, pea, radish, spinach, snow peas, Swiss chard and turnip. Most are easy from seed but cabbage, broccoli and other cole crops [Brussels sprouts, cabbage and cauliflower] are best transplanted into the garden so they can be planted deep enough to cover and support the bends typically found in young stems.

I think that arugula ought to do well too, given the leafy greens that are on the list.

I'm also about a month behind his suggested planting schedule, but maybe my proximity to the coast will help keep temperatures up for germination.

Rain 0.11"; season total 2.04"

2010-11-08T11:35:00.000-08:00

I was surprised by overnight rainfall totaling 0.11" this A.M.

A co-worker who lives in the inland areas stated that it fell hard at his house, but it was gentle at mine.

Magical rain barrels versus the world

2010-11-07T07:00:00.000-08:00

I've previously talked about the kind of collection efficiencies that rain barrel users can expect. They are typically dismal unless you have a very large barrel or the right kind of rainfall pattern. Collection efficiency depends on the rainfall pattern since one large storm would overwhelm most storage systems, thereby wasting the majority of the rainfall whereas a large number of small storms might never once overflow a typical barrel system. In the latter case efficiency would be 100%.

Based on typical southern California rainfall patterns I estimate a typical rain barrel collection efficiency at 10-20%. This is based on my previous analysis after throwing out the highest and lowest rainfall years and applying a factor of two reduction in efficiency, since the numbers I calculated were best case, and nobody is that diligent. Susan Carpenter of the LA Times spent $500 on two rain barrels and received a third for free. If the roof area she captured rain from was 1500 sq ft, then her cost per square foot would be $0.33 for 10-20% efficiency. She was happy to pay it, and I guess that speaks to the psychological impact of having a seemingly large amount of water deposited, as if by magic, in your barrel.

But is 100% efficiency achievable and cost effective? Yes, just about.

We know that some city codes require new construction to keep all* rain water on site. In fact, Bad mom recently blogged about the new Redondo Beach Library that has a swale and infiltration area intended to do just that. Let's call the collection efficiency of this engineered infiltration area 95% to account for the fact that "all" is probably not really all. Here's a Google Maps snapshot of the Redondo Beach Library being built. The infiltration area will end up being at the south end of the dirt lot and will infiltrate rain from 25,000 sq ft! You can estimate the size of the lot too, based on the 50x100' lot sizes of the surrounding homes.

If Susan Carpenter's roof area is 1500 sq ft and that required 3 rain barrels to get 10-20% efficiency, how many rain barrels are needed to capture runoff from 25,000 sq feet of lot? At 95% efficiency? The answer is far too many.

Suppose the infiltration pit at the North Redondo Beach Library added $20,000 to the cost of the project (this link says the whole project was $6 million so this is 1/3 of 1%). I have no idea what the actual cost increase was, but this seems like a good starting point for a construction project of significance. The lot is 25,000 sq. ft. as I noted above and they capture 95% of the rain from that lot. Then the cost per square foot is $0.80. Don't forget: That's at 95% efficiency! If we all agree that we ought to save rainwater, then shouldn't we be happy to pay $0.80 per square foot when the efficiency is so much higher and the area served is so much greater than that achievable with rain barrels?

The cost numbers get more lopsided if you factor in efficiency directly. Then we have a cost of $2.22 per square foot per point of efficiency for rain barrels and a cost of $0.84 per square foot per point of efficiency for infiltration.

You say to me, "I'm just a homeowner. I don't have $20k for an infiltration pit. All I have is $500 for some measly rain barrels" And I'd have to agree, $500 isn't too much. But it's not nothing. Unskilled labor costs $10-15 per hour, so with $500 you and your unskilled labor could regrade your lawn to include a slight berm on the downhill side and direct your roof runoff onto the lawn. The details are probably long enough for another blog post, but it's money better spent than on rain barrels.

And there's no magic involved.

*"all the rainfall" of course has an engineering definition that probably has to do with the mean rainfall in a storm plus some margin so in a very heavy storm not all the actual rain runoff will be captured.

Madrona Marsh demonstration garden

2010-11-06T07:01:00.000-07:00

The native plant demonstration garden around the Madrona Marsh visitor center is open whether or not the Marsh is open. While visiting, I met a Torrance city employee and another couple members of the public who were enjoying the gardens.

One reason I had for going was that I had previously identified a small grove of Salix exigua (Narrow-leafed Willow) as particularly pleasing. They had reminded me of bamboo glades in both form and height and I thought them quite elegant. The grove is now closer to a thicket - I think some thinning would be required to maintain the bamboo look over the years but perhaps the look is also dependent upon the growth cycle. I still think it's a pleasing shrub, below at a distance.

Other plants had their autumn finery on:

Erigonum

'Rogers Red' grape identified in the sign as Vitus californica. However we now know that is not true. DNA analysis tells us that 'Rogers Red' is a first generation cross between Alicante Bouschet, a less widely known Vitus vinafera grape used traditionally as a vin de tincture in winemaking and our native Vitus Still looks great!

Catalina silver lace looked luminous.

This plant struck my fancy because of the jaunty dried stalks, though I don't know its name.

Finally, Ceanothus 'Dark Star' - the same that recently died in my yard - shows that branch dieback is more typical than one might suspect.

- Posted at great expense from my iPhone

Magical rain barrel psychology

2010-11-03T23:47:00.000-07:00

In earlier posts I first exposed the cult of the rain barrel as a marginally efficient sop to green guilt but then had an Ah Ha moment in the second post when I related the prevailing theory of how unengaged people will become engaged people through the magic of rain barrels.

The magical rain barrel theory says that Flo and Joe Sixpack will suddenly throw off years of disengagement and disregard for the environment after receiving a free rain barrel from the City of LA(1) After work Joe will park his 4WD full sized truck in the lot-length driveway of their 50's era SFR, amble over to the rain barrel, and switch on the irrigation for his organic free-range tomatoes. He'll share the tomatoes down at the local VFW Hall and, over cold Budweiser, tell the story of the enabling technology of the rain barrel. In doing so he will spread the true gospel. It'll be viral!

FAT CHANCE.

This theory only works on people that are already on the cusp of wanting to do something green. Among LA's west side population I'll take a guess that fraction is at most 5% of households. So if you want to make inroads in 5% of households, go ahead and give out free rain barrels. Heck, I'll take one, though even on my somewhat capacious lot I don't know where I would conveniently keep it. On second thought, cancel my rain barrel. Just send me a crew of workers for a weekend to redo the drainage in my yard to more effectively infiltrate water on site.

What sorts of efficiencies push people's buttons and get them excited and engaged? Hardnosed reporter Susan Carpenter, the Realist/Idealist of LA Times was so thrilled with her $500 investment in 3 rain barrels that she put it at number three on her top list of green innovations. She lived with them for the past two to three years and based on my guess that her roof was larger than 600 square feet, she was probably getting rainwater collection efficiencies no better than I cite in my first blog post - 20% to 47% (her roof is larger but her total barrel size is larger too so these numbers are educated guesses for sake of discussion). But because no one is as efficient as the hypothetical water stud in that post, let's assume Susan had an actual 10% to 24% efficiency out of her rain barrels. She says that it lasted her a month into summer.

And she got excited! So here's a person with green tendencies, presumably somewhat skeptical (she is a Realist, after all) getting excited over an outlay of $500 that netted one less month of watering their fruit trees in summer.

I guess magic does happen.

1. "The City of Los Angeles, Department of Public Works, Bureau of Sanitation, Watershed Protection Division (Stormwater Program) rolled out the City’s first free Rainwater Harvesting pilot program in July 2009.
Residents that sign up for the program will be eligible for complimentary installations of (1) rain barrels (2) downspout disconnections, or (3) custom-made planter boxes for businesses. The captured rainwater will then be either routed to pervious surfaces or used for on-site irrigation."

OFG Hands On Workshop event wrapup

2010-11-01T18:02:00.000-07:00

Last Saturday I went to the Hands on Workshop (HOW) that I had heard about through my Ocean Friendly Gardens class participation (see Ocean friendly garden landscaping class wrapup) The workshop covered implementing a site evaluation using a worksheet to calculate current water use, runoff, and a water budget for conversion of a Torrance single family residence to an Ocean Friendly Garden that uses rain water. My goal was to check and cement the knowledge that I gained since I started to install my own native plant garden. I know that I made a lot of decisions based on less data than I could have had and when I build the next garden I want to have a bit more basis for my decisions. I was also interested assessing in the community interest OFGs.

The next step at this residence will be to incorporate the ideas into the Garden Assistance Program Workday (GAP) on Friday, November 26, 10am-4pm. This household is participating in the Garden Assistance Program whereby successful applicants get assistance to have their gardens reworked into ocean friendly gardens. I believe they are paying for plant materials and garden supplies, but the labor and design advice are provided at no cost. The homeowners were very gracious and welcoming (particularly considering that we were tracking mud all over their yard) and provided a light lunch with some delicious homemade berry and guava preserves.

The cost of the HOW, attended by perhaps 40 or more people, was free to the attendees though in the past charges have been up to $25 per person. This underwriting was provided by the City of Torrance since this is the first well-publicized garden conversion in the City of Torrance, who also plan similar garden conversions at several public sites around the city in an effort to reduce water use and provide demonstration gardens.

A (the?) top Torrance water manager was there and stated that Torrance will be moving to more recharge and use of local aquifers and to a four tier water rate system where the top rate will be more than twice the lowest rate, making gardens like this one a possibly significant contributor to the local water economy. It's interesting that no one ever mentions rationing at these meetings without first and more prominently mentioning tiered rates. I figure that aggressive tiered rates is the standard public answer to "what about rationing" types of questions. I hope that it is sufficient because no one is actually talking about real water rationing in California, such as would result immediately from significant infrastructure failure in northern California, or gradually due to continued severe drought. I've not heard of emergency water tiering, whereas emergency water rationing has a more familiar ring. At the class, West Basin Water District representative Carol Kwan related how rationing worked when she lived in Hong Kong: Water was turned on for 4 hours every three days! During the time water was on they filled every pot in the house with water to last through the next three days!

The workshop was useful, the instructors friendly and approachable, and the participants seemed engaged. I'm judging the community interest high based on the number of participants. I also felt particularly rewarded to get the straight skinny in regards to clarifying my mystification at the cult of the rain barrel. I did a little practical garden work, digging a hole to assess soil compaction (over 30 minutes to drain means it's compacted), learned that you only need to remediate soil to the depth of your largest plant (about 12" for 1 gal plants (soil flora and fauna will do the rest), and assessed drainage, learned to identify fungal hyphae and did some figgerin' on soil type and exposure for use in evapotraspiration calculations.

Walking in LA

2010-11-01T12:08:00.000-07:00

I came across Where the Sidewalk Starts blog today and found it an interesting read. I have to confess that I was searching for the straight skinny on how I (as a motorist) need to yield to pedestrians. I found that information in a post titled "A Confession A primer on the finer details of crosswalk law."

Rain barrels redux or Why I can now live in the same world as rain barrels

2010-10-30T16:52:00.000-07:00

In a previous post I calculated some optimum efficicencies for rain barrels in sizes of 55 gallons and 110 gallons in support of my feeling that I don't really care for rain barrels. After I had calculated their efficiencies I still wasn't convinced they were a good idea. Today I had the opportunity to ask a garden professional about rain storage and rain barrels when I attended an Ocean Friendly Gardens Hands On Workshop. More on the HOW later, since I know you are all so interested in this garden professional's opinion on rain barrels.

She said, "Rain barrels are the gateway drug to an ocean friendly garden", as near as I can recall. Just as I already knew, just as I already calculated, and just as the workshop today taught, soil is the preferred method of water catchment. But for those who live in blissful ignorance of their impact on downstream flow, rainbarrels raise awareness in an effective way. The rain barrel owners get engaged and that engagement leads to even more effective changes on their properties. Oh, and if you have a vegetable garden or some area that needs a bit more water like fruit trees then by all means use a rain barrel if it meets your space and aesthetic requirements, They do after all provide soft water for free (ignoring the initial costs). But don't look to even a couple 55 gallon barrels as your primary line of defense in a water wise garden.

That was the gist of the insight that I received today, which was well worth the price of admission (several hours of my time plus I learned a few other things). Ahhh...Finally, a rational thought on rain barrels. Given all the hype, I was losing hope that it was out there, but was.

Rain 0.30"; season total 1.93"

2010-10-30T16:38:00.000-07:00

We had a nice early morning rainfall that left us with 0.30" of rain. My downspout diverters, which I have been using for years in lieu of a rain barrel to cache water in my garden, worked flawlessly.

Why I don't think rain barrels are a good idea

2010-10-29T16:53:00.000-07:00

You are a rainwater stud or studette! You are such a rainwater stud that you operate your rain barrel in a way that any time there's a day of rainfall you have an empty barrel ready to capture your roof runoff. You feel proud because this is a highly efficient way to manage your rain water. In fact, it's nearly the most efficient way to use your rain barrel. You're so good that even if we have several consecutive days of rain you manage to have an empty rain barrel at the start of each day. I don't know how you do it, but this is what makes you the rainwater stud. At the end of the wet season, how many gallons of runoff have you saved?

I'll try to answer this question and others as I dig into rain barrels in an effort to convince myself that they are a good idea.

There's good instructions on the web for sizing and building rainwater catchment systems. The more comprehensive ones have disclaimers such as, "However, rainwater harvesting for landscape irrigation may only be practical in locations where rainwater can be collected in sufficient quantities during the time that it is needed," which I pulled from the linked web page (from Texas).

Susan Carpenter, the Realist Idealist of the LA Times ranks her three rain barrels third on a list of good eco-innovations - right behind gray water and solar photovoltaic panels and ahead of earthworks (passive garden design to capture rainwater), the Australian waterwall (a narrow rectangular rain barrel that looks like a wall), edible landscapes, and composting toilets. See Composting toilets, backyard chickens and waterwalls: Susan Carpenter's eco-living experiment

She spent $500 ($300 for two rain barrels (a third was free from the city) and $200 for installation and parts) and writes of the rain barrel experiment,

I was a rain barrel skeptic before I joined L.A.'s rainwater harvesting pilot program last fall.... Though rainwater holds such enormous potential for supplementing Southern California's dwindling reserves of imported water, rain barrels seem like such thimbles. During a normal L.A. winter, my 1,500-square-foot roof generates 13,500 gallons of water — a tidal wave compared to what a little barrel can handle.

Which is my concern exactly, but I don't think that under most circumstances that it's best mitigated by her next observations:

Having lived with rain barrels for a year, I've learned that their small size makes them manageable and affordable. The water they catch isn't stored only for summer use. It can be drained in between rains to water nearby plants. An added perk: reducing storm-water runoff to the ocean.

...The 175 gallons they hold were a lot more useful than I'd expected for feeding my exceptionally thirsty fruit plants. The water they held lasted about a month into the summer.

Under certain circumstances (for instance, your roof drains to unavoidable hardscape and then directly off property) I can see a benefit of rain barrels, but for the vast majority of suburban homes I can't see the ecological benefit over garden infiltration. There will almost NEVER be a cost savings if Ms. Carpenter's costs are typical: $500 for three unsightly barrels?

Let's try to put some numbers to my misgivings.

Let's assume that you, the rainwater stud, have 600 square feet of roof (half of a modest sized suburban home's roof area) and a 55 gallon rain barrel. Then it would take about 0.15" of rainfall to fill the barrel (using a conversion of 231 cu. in. per gallon). That means that after 0.15" of rainfall any additional rain is not captured!

Looking over the last six years of rainfall information in my own LA-area backyard (One of my not so private obsessions is rainfall statistics. I'm using my daily records of rainfall to make the tables below. You can do the same thing with a modicum of effort, an Excel spreadsheet, and the daily rainfall tallies for your area. Note to Steve Libby: Naturally I predicted the statistical utility of this data years ago when I started recording rainfall :-)

I'm also assuming I made no mistakes with the analysis, something that has not always proven to be the case, but the numbers seem to be what I expected and time is growing short so with an arrogant tip of my nose I'll take the "meets my expectation" observation as confirmation that they are indeed correct. Most of LA and a wide area of coastal southern California should be similar to what I present below. In fact, the inclusion of our driest year (06-07) and our wettest year (04-05) probably bounds the calculation for most of southern California: you should have results no worse and no better than predicted in those years.

Finally, with caveats and rambling prose out of the way, I can make the assessment of the impact that a rain barrel would have had on the rainwater stud's runoff, had he or she sited it in my backyard in any of the preceding six years:

There are two cases below. They use identical rainfall patterns (that of my back yard for the given years) and identical roof area (600 square feet). They differ in the size of the rain barrel. [Note that the number of down spouts doesn't matter. I assume ALL the rain from a 600 sq ft roof goes into the barrel or barrels. I'm writing this parenthetical note in response to a comment I received elsewhere suggesting that I add downspouts.] The upper table gives values for a 55 gallon rain barrel and the lower gives values for a 110 gallon rain barrel. In our recent wettest year, 2004-05, a 55 gallon rain barrel would only have been 11% efficient at capturing rainfall but would have been 65% efficient in our driest year (2006-07). For the case of the 110 gallon rain barrel the numbers are 19% and 99%, respectively. Average efficiencies are 0.47 for 110 gallon rain barrels and 0.29 for 55 gallon rain barrels.


55 gallon rain barrel, 600 sq ft of roof

110 gallon rain barrel, 600 sq. ft of roof

I have to admit that the efficiencies are surprisingly high, particularly with larger capacity barrels. However, our assumptions tell us that our rainwater stud isn't always using the water when it's most needed in the garden, which is between storms. Instead, over consecutive storm days that exceed capacity the barrel has to be drained to get the kind of efficiencies that you see here: you actually would have to water with your barrel while it was raining in many cases. Consider also, that 600 sq ft of roof is only half of a small 50's era SFR roof. For larger homes the runoff will increase in proportion to the roof area driving efficiencies down for the two cases set forth above. I'll leave this post as it is now, with a high likelihood of a return visit to this topic later when I can stand to think about this again.

More locally-relevant information about rain barrels is contained in a fairly thorough document that does not address rain barrel efficiency at www.larainwaterharvesting.org.

Dawn harvest

2010-10-26T08:12:00.001-07:00

Looks like enough for paella?

- Posted at great expense from my iPhone

Rain 0.28"; Season total 1.63"

2010-10-25T09:18:00.000-07:00

0.08" on 23 Oct
0.20" on 25 Oct - nice overnight rain with beautiful blue skies on the morning of the 25!

A total of 0.28" in a couple days is the nice sort of rainfall that makes gardens grow.

We're in between rainfall totals from the previous 6 years at the same date: three were greater and three were less. If direct comparison to historical LA averages are to be trusted, we're well above both mean and median rainfall for the end of October, so we're running a little wet early in the season. Forecasters are predicting a dryer than normal winter, however, so it might be best to make ~~hay while the sun shines~~flowers while the rain falls.