Fall Field Work

| No Comments

Kate and I have had some beautiful weather for field work (except today--it rained most of the day). Here's a picture of the roadside site we call East Riley. Notice that our ambitious mower has mowed TWO swaths of the roadside. The mowed area includes most of the circles I am searching to re-find and measure plants we had identified in years past.
P9121847web.jpg

We do seedling searches every spring at 14 prairie remnants. We search within 41 cm (or 50 cm for smaller populations) of randomly selected Echinacea plants that flowered the previous summer. Since 2006 we have used these spring searches to find new seedlings (identifiable by the presence of cotyledons). When we find seedlings, we draw circle maps showing the seedling locations with respect to the focal plant, and make measurements to other tagged plants. In 2009 and 2010 we mapped ALL Echinacea plants within the 41/50-cm radius circles. Late in the growing season, we return to the 14 sites and re-find the seedlings and other plants. We update the circle maps, and measure the surviving plants.

Why go to all this trouble? I plan to use the data to estimate the growth rate for these small Echinacea populations. Are the Echinacea producing enough offspring to maintain their populations? That's the question I hope to answer!

The re-finds are complete at eelr, lih, nessman, nwlf, randt, sap, sgc and spp. I am currently working at eri; still remaining are eth, kj's, lc, lf and ri. Some of the sites are disappointing. There has been a lot of gopher activity at lih, and most of the Echinacea plants, big and small, are gone. I was only able to find 1 of the 12 seedlings we had previously mapped. Other sites (eri, ri, nessman) are disturbed by frequent roadside mowing and scraping. In spite of that, we were able to find 18 of the 23 previously identified seedlings at nessman. In total (so far), we have found 54/85 seedlings. Some of the survivors were first identified in 2007 (I don't think I've found any 2006 seedlings yet--but there weren't many to begin with).

I'll post an update when I finish entering all the data...or the next time I get rained out!

Leave a comment