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The Global Invasive Species Team | |
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Global Invasive Species Team listserve digest #017 Fri, 29 Jan 1999 18:07:42 -0800 (PST) --CONTENTS-- 1. More On Weed Mapping 2. Colorants in Garlon 4 3. Weed Surveys and Kite Flying --------------------------------------- 1. More On Weed Mapping From: Marilyn Jordan (mjordan(at)tnc.org) Two weed species in a 5 acre portion of the Hempstead Plains on Long Island, NY were mapped using permanently marked, surveyed reference points to divide up 20 m x 20 m squares into 2 m wide, parallel strips measured out with a 50-m tape. Several classes of biology students from a nearby university walked each strip, and for each 2m x 2 m square along the strip they recorded a code for the cover of two weed species (>90%, 10-90%, <10%). A lab assistant created a grid map using a different density of shading for each cover class. The students at first had tried to draw boundaries around patches of weeds but that did not work, since the weeds were diffusely distributed with no clear patch boundaries. The "strip method" could be modified by reducing the size of each unit square to get more detail, or by enlarging the squares to cover a larger area with less detail. One disadvantage of this method was vegetation trampling by dozens of students. The biological impact of the trampling was minimized by doing the mapping in late September, at the end of the growing season. Marilyn Jordan, Ph.D., Stewardship Ecologist The Nature Conservancy, Long Island Chapter 250 Lawrence Hill Road, Cold Spring Harbor NY 11724 phone 516-367-3384 x 21; FAX 516-367-4715; mjordan(at)tnc.org --------------------------------------- 2. Colorants in Garlon 4 From: Randy Tate (gtate(at)tnc.org) I didn't have luck using colorant in Garlon 4 used on Australian pine in the Keys. I used Blaze-on and found it not very visible and fast to fade. Maybe I didn't mix it adequately; I don't know. What colorants are being used with success? G. Randall Tate Director of Stewardship Ops. & Fire Mgmt. 250 Lawrence Hill Rd., Cold Spring Harbor, NY 11724 (516)367-3225, ext. 24; e-mail: gtate(at)tnc.org --------------------------------------- 3. Weed Surveys and Kite Flying From: Barry Rice (bamrice(at)ucdavis.edu) This is just about the last call for the weed surveys. Have them in by the 15th or miss out on all the fun! Incidentally, George Gress pointed out the "guy with the kite" mentioned in Weeds Digest #16 is Steve Eisenhauer, from the Delaware Bayshores Office! --------------------------------------------------------------- |
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