I find it hard to believe that the following invasive species are not = having catestrophic affects =20 Honeysuckle in the Ozarks: Crowds out forest floor vegetation Lespedeza: Crowds out just about everything where it grows Multiflora Rose=20 water hyacinth chokes off waterways and crowds out native vegetation european grasses interact with native grasses Chinese Tallow crowds out many species in cypress-tupelo swamps Sugar Maple in Midwest Oak Forests (some invasives are native) prevents = seedling trees from advancing into the canopy Sweet Gum in wetland forests same effect as sugar maple. =20 Certainly I haven't even scraped the surface.... This is one big messed up ecosystem we have created =20 =20 Malcolm L. McCallum Assistant Professor Department of Biological Sciences Texas A&M University Texarkana 2600 Robison Rd. Texarkana, TX 75501 O: 1-903-233-3134 H: 1-903-791-3843 Homepage: https://www.eagle.tamut.edu/faculty/mmccallum/index.html =20
________________________________ From: Ecological Society of America: grants, jobs, news on behalf of = [EMAIL PROTECTED] Sent: Tue 4/4/2006 12:46 PM To: [email protected] Subject: Re: invasive plants >From what I see exotics doing to the systems around me, I would say extirpations are a bigger problem than extinctions -- same effects as extinctions but on a local scale. All these local, small scale effects when considered as being repeated many times over a large area add up to = a big impact. Mike Gross = =20 Teresa Woods = =20 <[EMAIL PROTECTED]> = =20 Sent by: = To "Ecological [email protected] = =20 Society of = cc America: grants, = =20 jobs, news" = Subject <[EMAIL PROTECTED] invasive plants = =20 V.UMD.EDU> = =20 = =20 = =20 04/04/2006 10:56 = =20 AM = =20 = =20 = =20 Please respond to = =20 Teresa Woods = =20 <[EMAIL PROTECTED]> = =20 = =20 = =20 My understanding from the ecological literature is that invasives are not responsible for nearly as many native species extinctions as one would intuitively imagine, and mostly only when trophic interactions, mainly predation, are involved. Invasive plants, rather than causing extinctions among native plants, appear primarily to change and disrupt ecosystem function through shifting dominance patterns, fire regimes, etc. I have been surprised about the lack of documented native extinctions due to invasive plants (main exceptions seem to be isolated island systems). My question: are there studies / documentation to support the idea that invasive plants cause, or are at least correlated with, native plant extinctions? Just to conflagrate the issue here, here's a link to a recent NYTimes opinion article from a horticulturalist in the issue of invasives -- a view from the other side of the fence! http://www.nytimes.com/2006/03/19/opinion/19ball.html?ex=3D1144296000&en=3D= b173e8d3fdb8d5e2&ei=3D5070 Teresa Teresa Woods Graduate Assistant Division of Biology 232 Ackert Hall Kansas State University Manhattan, KS 66506 785-532-9834 [EMAIL PROTECTED]
