Bringing Nature Home: How Native Plants Sustain Wildlife in Our Gardens by Douglas Tallamy has been next to my bed for a while. It's been out since 2007, so it's not exactly fresh off the presses. Slow starter that I am, I finished it only recently and thought I'd post a quick review and brief notes, since it has occasionally been the subject of controversy.
The bottom line is that I like and recommend the book. It's written in an approachable manner, with many fascinating color pictures that amplify on the text and the topic is timely given the increase of green thinking that is sweeping the nation.
The first half of the book is valuable to all gardeners. But starting around chapter 10, the book becomes much more focussed on east coast flora, and therefore of less interest to those outside that area. The opinions in the book are supported by citations from scientific literature and personal anecdote, though Tallamy admits that the data are incomplete and much work remains to be done. Nonetheless, he convincingly makes the case that extrapolation from the knowledge that we presently have suggests that urban and suburban gardeners can remediate the damage that human presence has had on the wild food web. (The food web is an extension of the grade school concept of the food chain, but with multiple redundant paths up and down. This concept and current understanding that we have of "keystone species" - species that are essential to preserving the food web, are covered early in his book. It's interesting to note that I'm confining this to a parenthetical side note and considering not even mentioning it at all because of its obviousness, but apparently until somewhat recently these concepts were not commonly understood.) The tone of the book is not preachy or histrionic. He makes his case calmly, with facts, anecdotes, and extrapolation: From Tallamy's point of view, it's not too late to do something that makes an essential difference.
Tallamy is an entomologist at the University of Delaware in Newark, so he takes a look at how humans have altered the historically longstanding food web as we've expanded into previously wild areas from the standpoint of disruption at the insect level. Looking one level up and down the food chain from herbivorous insects (by total tonnage the largest group of herbivores in the world and whose predation accounts for the most abundant source of food energy in the world) he pieces together an argument supporting the expanded use of natives as follows:
Tallamy takes as his definition of native plants as species "having a historical evolutionary relationship" with their environs. This definition does away with arguments, for example, that one can take a plant from anywhere in North America and plant it anywhere else, so long as the USDA hardiness zones are the same, and call it a native. By contrast, alien species do not have a historical evolutionary relationship with their environs and therefore do not participate completely in their local ecosystems. In fact, the nursery trade has made a virtue out of "pest free" plants, in other words, aliens which won't support significant amounts of indigenous insect life.
Because native insects have a common evolutionary history with native plants, the insects have a preferred diet of native plants and in some cases exist only on certain natives. Alien plants nourish far fewer (in number and in diversity) insects than natives, even those that have been here for 100s of years. (100s of years is quite short in terms of evolutionary adaptation.) Because insects feed on plants and in turn are fed upon by higher trophic levels (mostly birds), reducing the number of natives will proportionately reduce the number of higher higher trophic levels supported.
As remedy, Tallamy proposes that urban and suburban gardens favor native plants over aliens in order to take the place of the diverse woods and wildlands that they have displaced. As a corollary, we must actively guard (or garden) remaining "wild" areas to prevent intrusion of aliens. These steps, he argues, are essential if we are to preserve the next higher link in the food chain - birds, mostly, as well as other small mammals that eat insects.
In addition to native plant species, Tallamy recommends high diversity both in species and in structure. Structural complexity means having varied types of plants (grasses to trees and everything in between). This is logical from the standpoint of replicating the diversity of native habitats which provide for the habitat needs at many more cycles of life: The insect herbivores need both larval and adult food which are often completely different plants.
Finally, he points out that the beneficial insect predators that you want in your garden (such as ladybugs) need populations of prey insects (such as aphids) to sustain them or they will abandon your garden. Therefore the co-existence of small numbers of "pest" insects is necessary to ensure that the beneficial ones are there when you need them. Your garden won't be perfect, but he cites a study showing that even the most gardeners won't notice or perhaps care about 10% leaf damage, so there's the possibility of peaceful coexistence of a variety of insects, in balanced numbers, with peoples' requirements for nice looking plants. As for where to put these plants: He suggests shrinking your monoculture lawn and expanding your hedgerows to incorporate natives and increase diversity in a subtle way.
Here's an illustrative quote from the book on the topic of diversity.
In the East, the number one pest of ornamental gardens is the azalea lace bug (Raupp & Noland, 1984). This bug was introduced along with evergreen azaleas from Asia and now sucks the chlorophyll from alien azalea leaves wherever the plants are massed in a sunny setting, although the bugs won't touch our native azalea species. Why don't natural enemies, the insect predators and parasites native to North America, control this pest? Because the community structure of most of our gardens is far too simple to support the numbers and diversity of natural enemies required to keep the azalea lace bug in check. Picture a classic suburban foundation planting: a row of Asian azaleas along the front of the house, bookended by two arborvitaes. Just where are the natural enemies needed to control the lace bug supposed to come from? Ladybird beetles, assassin bugs, damsel bugs, and parasitic wasps can only live in a garden if there are enough types of prey available to support them at all stages of their life cycle. Because our classic suburban foundation planting is dominated by alien plants, the only insect available to support a community of predators is the azalea lace bug. When the lace bug population is small, which is the critical time for predators and parasites to prevent an outbreak, there simply is not enough [other] prey biomass in the garden to attract and support populations of natural enemies. And so the lace bug population explodes, the homeowner runs for the insecticide, and the goal of having an undamaged garden is lost.
One of the areas where Tallamy has come in for criticism is in his recommendation of trees as primary insect habitat. Of course, for habitats that didn't originally have a lot of trees, such as the California coastal prairie habitat originally around my house, this makes little sense. However, a reasonably careful reader of his book will note that in chapter 12 he writes, "I am also forced to slight western North America and focus on...eight states of the easter deciduous forest biome.... I restrict my discussion to this region because it is the only area for which we have done an exhaustive literature search for host plant relationships." So casual readers may misunderstand his writings, but the disclaimer is there for all to see, and the results are still quite interesting.
Working with moths and butterflies (Lepidoptera) as representative of all insect herbivores (apparently they represent over 50% of all insect herbivores in this country, so this is a good first choice) he then sets forth some interesting findings: Among woody plants, Oaks support the most Lepidoptera with 517 species, willows are next with 456, and Walnut, Beech, and Chestnut trees bring up the bottom of the list with 130, 126, and 125 each, respectively.
It's probably zeroth or first order correct to pull the tree genus' native to California directly from his list and assign them that relative rank in terms of insect value. However, there is no mention of the contributions of other plant types (groundcover, vines, shrubs, cactus, etc) so for areas of historically sparse woody plants, like California coastal scrub or prairie, there's no equivalent starting point to make most effective use of California's other plants.
Read an interview with Tallamy on Garden Rant.
A related link to BUGS - Biodiversity in Urban Gardens.
Showing posts with label books and music. Show all posts
Showing posts with label books and music. Show all posts
2008-03-24
2008-02-18
The Omnivore's Dilemma - commentary
Michael Pollan is getting a lot of attention for his recent book, In Defense of Food: An Eater's Manifesto. (tag phrase: "Eat food. Not too much. Mostly plants.")
I buy used books, so I'm reading his previous book, The Omnivore’s Dilemma: A Natural History of Four Meals (2006).
I'm about 3/4 of the way through the book and it's been a fascinating tour of our industrial agricultural food system, our industrial organic food system, a beyond organic / local food system, and in the final pages a local hunter/gatherer food system.
His complete message is nuanced and best read and interpreted for one's self, but one obvious take home message is that there are glaring problems with application of industrial techniques to food production. A brief summary of the guiding philosophy one could take home from the book is here.
The introduction and first chapter of The Omnivore's Dilemma (PDF)
Other writing by Michael Pollan.
I buy used books, so I'm reading his previous book, The Omnivore’s Dilemma: A Natural History of Four Meals (2006).
I'm about 3/4 of the way through the book and it's been a fascinating tour of our industrial agricultural food system, our industrial organic food system, a beyond organic / local food system, and in the final pages a local hunter/gatherer food system.
His complete message is nuanced and best read and interpreted for one's self, but one obvious take home message is that there are glaring problems with application of industrial techniques to food production. A brief summary of the guiding philosophy one could take home from the book is here.
The introduction and first chapter of The Omnivore's Dilemma (PDF)
Other writing by Michael Pollan.
2007-12-30
Theodore Payne In His Own Words
subtitled, "A voice for California Native Plants" was one of my Christmas reads. I received the book from Juli because of my interest in native plants, but it's only tangentially about native plants. The book is written in three parts. The first part is a fairly detailed account of Payne's life as a ranch hand on the Modjeska Ranch, now known as Modjeska canyon and one of the sites of recent wildfire in Orange County. The second and third parts of parts of the book are anecdotes about the nursery trade. There's a lot of local place references, so for someone who knows the South Coast it sounds like familiar territory.
Here's some of the parts I found interesting:
One afternoon my wife and I went to Redondo Beach. We walked out onto the sand dunes where I usually collected seed of Bush Sunflower, White Snapdragon, and a few other things. I found the Beach Wallflower was ripe, so while I gathered some of the seed, my wife sat down and read a magazine.
Pretty soon a woman came along..."What's it good for, rheumatics?...Makes a good tea, eh?" she exclaimed and started furiously to grab all she could. If she saw a plant before I did, she would try to beat me to it. I was only interested in the seed spikes but she took the whole plant. After gathering all she could carry in her apron she left. (Seed Collecting at Redondo Beach, p. 131)
From Goleta I went by train to Ellwood Station to visit the Ellwood Cooper ranch. Ellwood Cooper came to Santa Barbara in 1870 and bought this ranch. he became interested in growing eucalyptus and by 1875 had 50,000 trees growing....
I enjoyed meeting them very much. I visited this place on a number of occasions in later years and Fanny Cooper, one of the daughters, collected seed of various kinds of eucalyptus for me. (p. 95)
During the Eucalyptus boom in Southern California which started in 1907 and continued for five years, there was a good demand for young eucalyptus trees in flats. Quite a number of small Eucalyptus Nurseries sprung up almost overnight. Many of these were operated by people who had regular jobs and who did this work in their spare time. A man would rent a vacant lot, have a water meter installed, purchase a quantity of flats and seed and raise perhaps 50,000 or 100,000 trees.
I supplied many of these dealers with the seed and helped dispose of their young plants....On one occasion I had a customer for a carload of young trees of the Red Gum (Eucalyptus rostrata) to be shipped to the San Joaquin Valley. I made arrangements to buy these trees from a man who raised them on Crocker Street. He was a stock broker by profession and had taken up eucalyptus raising as a side line. (p. 132)
The Eucalyptus boom burst about 1912. There was now no demand for seed or trees. I had over 100 pounds of seed on hand. Nobody wanted it. (p. 145)
There's no lesson here about the housing market, is there?
In April 1896 I entered the employ of the Germain Fruit Company, Seed and Plant Department....In those days Germain's handled pampas plumes which were then grown extensively here in Southern California. I represented the firm on this trip and sold over 40,000 of these dried plumes on London, Hamburg and Erfurt. (p. 191)
When I first came to California, what impressed me perhaps more then anything else was the wonderful native flora. But as the years went by it was with deep regret that I saw the wildflowers so rapidly disappearing from the landscape. I made up my mind that I would try to do something to awaken a greater interest in the native flora. Thus it was the a I began to specialize in the growing of wild flowers and native plants. I collected seed of a few kinds of wild flowers, grew then and offered the seed for sale.
Little or no success attended this first venture, it being generally conceded that it was foolish to waste time on "wild flowers." As a demonstration I secured the use of a vacant lot in Hollywood and sowed it with wild flower seeds. I went to Walter Raymond of the Raymond Hotel in Pasadena and asked him for the use of a piece of ground for sowing wild flower seeds. Mr Raymond readily consented and the following spring there was a splendid display. I also secured the use of two lots in Pasadena, one on Green Street and the other at the corner of Lake and Colorado, which I sowed with wild flower seeds. All these plots were greatly admired and I received complimentary letters from many people. This was really the beginning of wild flower planting.
My first wild flower catalog was a very modest little booklet published about 1906. (p.192-193)
Here's some of the parts I found interesting:
One afternoon my wife and I went to Redondo Beach. We walked out onto the sand dunes where I usually collected seed of Bush Sunflower, White Snapdragon, and a few other things. I found the Beach Wallflower was ripe, so while I gathered some of the seed, my wife sat down and read a magazine.
Pretty soon a woman came along..."What's it good for, rheumatics?...Makes a good tea, eh?" she exclaimed and started furiously to grab all she could. If she saw a plant before I did, she would try to beat me to it. I was only interested in the seed spikes but she took the whole plant. After gathering all she could carry in her apron she left. (Seed Collecting at Redondo Beach, p. 131)
From Goleta I went by train to Ellwood Station to visit the Ellwood Cooper ranch. Ellwood Cooper came to Santa Barbara in 1870 and bought this ranch. he became interested in growing eucalyptus and by 1875 had 50,000 trees growing....
I enjoyed meeting them very much. I visited this place on a number of occasions in later years and Fanny Cooper, one of the daughters, collected seed of various kinds of eucalyptus for me. (p. 95)
During the Eucalyptus boom in Southern California which started in 1907 and continued for five years, there was a good demand for young eucalyptus trees in flats. Quite a number of small Eucalyptus Nurseries sprung up almost overnight. Many of these were operated by people who had regular jobs and who did this work in their spare time. A man would rent a vacant lot, have a water meter installed, purchase a quantity of flats and seed and raise perhaps 50,000 or 100,000 trees.
I supplied many of these dealers with the seed and helped dispose of their young plants....On one occasion I had a customer for a carload of young trees of the Red Gum (Eucalyptus rostrata) to be shipped to the San Joaquin Valley. I made arrangements to buy these trees from a man who raised them on Crocker Street. He was a stock broker by profession and had taken up eucalyptus raising as a side line. (p. 132)
The Eucalyptus boom burst about 1912. There was now no demand for seed or trees. I had over 100 pounds of seed on hand. Nobody wanted it. (p. 145)
There's no lesson here about the housing market, is there?
In April 1896 I entered the employ of the Germain Fruit Company, Seed and Plant Department....In those days Germain's handled pampas plumes which were then grown extensively here in Southern California. I represented the firm on this trip and sold over 40,000 of these dried plumes on London, Hamburg and Erfurt. (p. 191)
When I first came to California, what impressed me perhaps more then anything else was the wonderful native flora. But as the years went by it was with deep regret that I saw the wildflowers so rapidly disappearing from the landscape. I made up my mind that I would try to do something to awaken a greater interest in the native flora. Thus it was the a I began to specialize in the growing of wild flowers and native plants. I collected seed of a few kinds of wild flowers, grew then and offered the seed for sale.
Little or no success attended this first venture, it being generally conceded that it was foolish to waste time on "wild flowers." As a demonstration I secured the use of a vacant lot in Hollywood and sowed it with wild flower seeds. I went to Walter Raymond of the Raymond Hotel in Pasadena and asked him for the use of a piece of ground for sowing wild flower seeds. Mr Raymond readily consented and the following spring there was a splendid display. I also secured the use of two lots in Pasadena, one on Green Street and the other at the corner of Lake and Colorado, which I sowed with wild flower seeds. All these plots were greatly admired and I received complimentary letters from many people. This was really the beginning of wild flower planting.
My first wild flower catalog was a very modest little booklet published about 1906. (p.192-193)
2007-11-30
Music
Unamplified speakers: The PSB Alpha B1 loudspeakers seem to be highly rated and in my price range ($279) as are the Paradigm Atom Monitor v.5's ($249). Onix x-ls speakers have a good review or two and more favorable pricing ($200)
When looking for loud speakers for computer systems, it seems that you can find only amplified systems. Of these, the M-Audio Studiophile DX4 seems to be rated highly for audio source materials (not games) and comes in at an affordable price point. Samson Resolv 40a's are similar (repurposed monitors) but have higher power ratings.
Music to look into: Miles Davis and Gil Evans' Porgy and Bess
When looking for loud speakers for computer systems, it seems that you can find only amplified systems. Of these, the M-Audio Studiophile DX4 seems to be rated highly for audio source materials (not games) and comes in at an affordable price point. Samson Resolv 40a's are similar (repurposed monitors) but have higher power ratings.
Music to look into: Miles Davis and Gil Evans' Porgy and Bess
2007-11-28
Last Child in the Woods
I've been reading _Last Child in the Woods_ by Richard Louv. He speculates upon a beneficial nature / mind link.
see http://www.thefuturesedge.com/
One of the central elements of Mr. Louv's thesis is that because nature is a highly enriched environment, it can have beneficial effects on peoples' (particularly childrens') mental states. He has a well-written argument that I won't repeat here.
My experience with my son at the Lair convinced me that Mr. Louv has a bead on some elements of truth. My son went to the Lair somewhat unhappy and came back much happier, a state that has persisted. His best activity there was unstructured play in the creek - exactly the sort of play that Mr. Louv states is most beneficial.
I am aware that you can draw an infinity of lines through one data point.
see http://www.thefuturesedge.com/
One of the central elements of Mr. Louv's thesis is that because nature is a highly enriched environment, it can have beneficial effects on peoples' (particularly childrens') mental states. He has a well-written argument that I won't repeat here.
My experience with my son at the Lair convinced me that Mr. Louv has a bead on some elements of truth. My son went to the Lair somewhat unhappy and came back much happier, a state that has persisted. His best activity there was unstructured play in the creek - exactly the sort of play that Mr. Louv states is most beneficial.
I am aware that you can draw an infinity of lines through one data point.
2006-12-01
Ethel - Light
I like Ethel's most recent release, which I downloaded from emusic.com but I'm at a loss as to how to describe the music to someone who has not already heard it since it's not my usual cup of tea and I find my vocabulary lacking. Tracks like Temporal Disturbances use voice samples to good effect, as well as percussive elements but it's mostly string-driven "classical" music with a modern interpretation. However, to put it squarely in the classical category isn't completely right. To me it seems to have elements of experimental music (all the wit and quirkiness with none of the randomness or atonality) and a sort of plucky rock / punk /pop sensibility, depending upon the tracks.
NPR has more information.
Edit 12/15: I've had more time with Light (still enjoying it) and I also downloaded Ethel's eponymous first release and can say with certainty that it is much less immediately accessible than Light. Ethel is to Light as la daube is to granita di limone - both satisfying, but in completely different ways. If you are curious about this group then start with their second release, Light.
NPR has more information.
Edit 12/15: I've had more time with Light (still enjoying it) and I also downloaded Ethel's eponymous first release and can say with certainty that it is much less immediately accessible than Light. Ethel is to Light as la daube is to granita di limone - both satisfying, but in completely different ways. If you are curious about this group then start with their second release, Light.
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