E. terracina pulled versus date: Is there a useful trend?

Here's a graph of number of E. terracina pulled versus date starting in 2013 and going to 1/2/2015.  This is based on my personal data from Lunada Canyon covering the same hillside area of perhaps 5000 ft^2.

I'm observing that:

Peak removal times are Feb, Mar, and April.  Cal Flora says bloom times are Mar-July.  Since bloom follows growth, this is consistent and it suggests that starting in February is the best time to catch the juvenile plants but that we needn't be on high alert after May if we've been diligent since February.  No fresh news here, just on-the-ground confirmation.

I removed about the same total number last year and the year before during peak season, but fewer seeds should be in the seed bank since the ones I removed generally had few ripe fruits.

We had a dry year last year, so the better rains we have now may improve the seed germination.

Look at that exponential-looking germination rate in early February, 2014.  In Feb 2013 there had been some prior efforts (not mine) and I didn't find the mother lode until my second trip to the site.

I didn't document my findings of no E. terracina plants observed well enough in the documents that I have at hand.  I should do this better.

An interesting, apparently linear, sub-trend exists from 10/19/13 to 12/22/13 which could be explained by having only about a 30%-50% chance of seeing plants when the plants are sparsely located.  Or it could have to do with crown sprouting plants continuing to grow and becoming visible as they re-emerge.  It suggests that early fall is a good time to make a sweep after taking time off from May's successful eradication.

This coming season's eradication numbers might be insightful to let us know how depleted the seed bank is becoming, assuming it's not confounded by the better rain.

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