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The Global Invasive Species Team | |
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Global Invasive Species Team listserve digest #112 Sat Jan 11 2003 - 17:39:58 PST --CONTENTS-- 1. Plant Invaders of Mid-Atlantic Natural Areas (Nationwide, USA) 2. Colorado bans more species (Colorado, USA) 3. CD-ROM version of Fading Forests II (Nationwide, USA) 4. Upcoming meetings (Nationwide, USA) 5. Effects of ATVs (Florida, USA) 6. Vermont bans almost 30 invasives (Vermont, USA) 7. Literature reviews (Global) 8. Reviews of papers on non-native plant eradication projects (Global) --------------------------------------- 1. Plant Invaders of Mid-Atlantic Natural Areas (Nationwide, USA) From: Jil Swearingen (jil_swearingen(at)nps.gov) A new 82 page guidebook has been published which provides color photographs and information on 49 species of highly invasive plants affecting aquatic and terrestrial natural areas in the mid-Atlantic region. The manual includes an introductory section explaining the invasive species problem, write-ups on each species organized by type of plant (i.e., aquatic, herb, shrub, tree, vine), suggested native plant substitutes, a glossary of terms used, references, and sources for more information. To request a copy, please call U.S. Fish and Wildlife Service, Chesapeake Bay Field Office at 410-573-4500; or Jil Swearingen, National Park Service at 202-342-1443, ex. 218; or send an email to Mary Cordovilla at: mary_cordovilla(at)fws.gov --------------------------------------- 2. Colorado bans more species (Colorado, USA) From: Damian Fagan (dfagan(at)tnc.org) Colorado has banned the sale of Russian Olive increasing the list of banned species to 16, including Dame's Rocket, Oxeyed daisy and salt cedar. For the complete article in the Denver post see: http://www.denverpost.com/Stories/0,1413,36%257E33%257E1028101%257E,00.html --------------------------------------- 3. CD-ROM version of Fading Forests II (Nationwide, USA) From: Faith Campbell (phytodoer(at)aol.com) The CD-ROM version of Fading Forests II Trading Away North America's Natural Heritage, is available. The report focuses on insects and plant diseases introduced to North America that have damaged native tree species, and especially on prevention issues: Why are introductions of insects and pathogens occurring more frequently? What can Americans (and Canadians) do to prevent even more pests from threatening our forests? We also discuss how the USDA Forest Service can better protect forests from those pests that have already become established. You may download the report from http://fwf.ag.utk.edu/Schlarbaum/selection.htm If you would like a high-quality copy of the report, a CD is available. To obtain the CD, please send $6 (US) to at American Lands Alliance, 726 7th Street, S.E. Washington, D.C. 20003 If you wish bulk copies, please contact me first. --------------------------------------- 4. Upcoming meetings (Nationwide, USA) From: Barry Rice (barrymr(at)ucdavis.edu) **Native Seed Quality Workshop/Omaha, Nebraska, 25-26 February This workshop will serve as a forum for those interested in the native seed industry. Sessions on the latest in native seed testing, conditioning, production, establishment and research will be presented by those with first hand knowledge and experience of the native seed industry. Cost: $200 More information: http://www.mwseed.com/workshops.htm **Idaho Weed Control Association Conference/Nampa, Idaho, 5-6 February This conference is for private landowners and agencies who have responsibilities for vegetation management. Topics include Biological Weed Control & Weed Ecology, Industry, Management & Restoration, and Smorgasbord (including Aquatics). Cost: $125 More information: http://www.idahoweedcontrol.org/weedconference.html --------------------------------------- 5. Effects of ATVs (Florida, USA) From: Doria Gordon (dgordon(at)tnc.org) In response to the listserve query from Dave Carr regarding ATVs, in Florida the Defenders of Wildlife has just completed a report called: Out of Control: The Impacts of Off-Road Vehicles and Roads on Wildlife and Habitat in Florida's National Forests. Copies of the report (about 140 pp) can be found at: http://www.defenders.org/habitat/florvs/. While invasion by exotic species along the corridors made by ORVs is mentioned in several places, a few more specifics are found on pp. 47-49 --------------------------------------- 6. Vermont bans almost 30 invasives (Vermont, USA) From: Rose Paul <rpaul(at)tnc.org) The Vermont Department of Agriculture recently adopted a rule banning the sale or transport of almost 30 invasive exotic plants; this is our first such regulation. Here's a link to the list: http://www.state.vt.us/agric/invasive.htm --------------------------------------- 7. Literature reviews (Global) From: John Randall (jarandall(at)ucdavis.edu) Clarke, A.L. and T. Pacin. 2002. Domestic cat "colonies" in natural areas: a growing exotic species threat. Natural Areas Journal 22: 154-159. You likely knew that domestic cats (Felis catus L.) can be a direct predation threat to native wildlife and that feral cats can be problem in conservation areas, particularly in sites near towns and cities. You may not have known, however, that a network of well-organized, well-funded groups which promote and practice a Trap-Test-Vaccinate-Alter-and-Release (TTVAR) approach to dealing with feral cats has emerged in the U.S. and other nations. Cats are usually released in designated "colony" sites and fed regularly in hopes that if well-fed they will not hunt wildlife and that, since they have been sterilized, their numbers will dwindle as individuals age and die. Unfortunately, conservation areas or lands adjacent to them are sometimes selected for "colony" sites and data indicates that fed cats still hunt and that at least in some cases colony sizes continue to increase as irresponsible owners continue to dump cats which are drawn to these sites by the food. The authors describe two examples of TTVAR cat colony management organizations operating in South Florida to illustrate how these operations may impact and interact with conservation areas. They also provide a set of recommendations for conservation land managers, urging them to take a pro-active approach to feral and abandoned cat problems by learning about relevant laws in their areas, working with other groups to educate the public on the importance of responsible pet ownership and of the damage that cats can cause in conservation areas before unmanaged or managed groups of cats become established within their areas. They also urge conservationists to work for passage of appropriate pet ordinances in their areas. Lym, R.G and J.A. Nelson. 2002. Integration of Aphthona spp. flea beetles and herbicides for leafy spurge (Euphorbia esula) control. Weed Science 50: 812-819. A series of experiments conducted at sites scattered across North Dakota revealed that a single autumn application of the herbicides picloram and/or 2,4-D to leafy spurge infested areas (150 stems m-2) where biocontrol agents (Aphthona spp.) had already been released, decreased the time it took the insects to bring the spurge under control (0-10 stems m-2), usually by several years. However, the biocontrol agents alone achieved the same levels of control after 3-7 years in most cases. In one site where the Aphthona flea beetles had been present for 7 years without controlling the spurge, a single autumn application of picloram plus 2,4-D was followed by an increase in numbers of the beetles and control of the spurge within a few more years. Spring-time applications of the herbicides actually increased the time it took the biocontrol insects to control the spurge. Since even autumn applications of the herbicides may reduce abundance of other broad-leaved plants, for conservation areas with similar climate and soil conditions the upshot here seems to be: 1. patience is a virtue and releases of the beetles should be enough to control the spurge on most conservation areas but it may take a few more years. 2. If the beetles do not control the spurge after 6+ years a single autumn herbicide application may jump-start the control process. Hoilway, D.A., L. Lach, A.V. Suarez, N.D. Tsutsui and T.J. Case. 2002. The causes and consequences of ant invasions. Annual Review of Ecology and Systematics. 33: 181-233. This is an excellent review of what is known of the roughly 150 species of ants that have invaded new environments, with an emphasis on what is really known about the impacts of these invasions on biodiversity. Most of what we do know comes from studies of just 6 of these species: red imported fire ants (Solenopsis invicta), Argentine ants (Linepithema humile), big-headed ants (Pheidole megacephala), long-legged or crazy ants (Anoplolepis gracilipes), tropical fire ants (Solenopsis geminata) and little fire ants (Wasmannia auropunctata), and there is still much to learn about these species. --------------------------------------- 8. Reviews of papers on non-native plant eradication projects (Global) From: John Randall (jarandall(at)ucdavis.edu) There is surprisingly little published information about the many alien plant eradication projects that have been attempted - some successfully and others unsuccessfully. Too bad, because there is much that we could learn about how to carry out eradication projects - and what not to do. Fortunately, the Cooperative Research Center for Australian Weed Management (Weed CRC) has begun to remedy this gap, at least for projects carried out in Australia. The Weed CRC sponsored a workshop on successful weed eradication projects at the 13th Australian Weeds Conference held in September, 2002 and five short but interesting papers based on the five presentations given there are now available in the Conference Proceedings (H. Spafford Jacob, J. Dodd and J.H. Moore (eds.) 13th Australian Weeds Conference Papers and Proceedings. Perth, Australia, September, 2002.). The title and brief summaries of all five papers are below. They are not available in electronic format but contact Barry Rice (bamrice(at)ucdavis.edu) if you would like hard copies. Tomley, A.J. and F.D. Panetta. 2002. Eradication of the exotic weeds Helenium amarum (Rafin) H.L. and Eupatorium serotinum Michx. from south-eastern Queensland. pp. 293-296. These two native North American members of the sunflower family (Asteraceae) were eradicated from separate sites in southeastern Queensland but it took many years. Helenium amarum was first detected in 1953 at a site 80 km west of Brisbane and ultimately spread to more than 50 hectares and a small satellite population 1.6 km away. It required a total of 370 person-days over a period of 39 years to eradicate this species from Australia. Eupatorium serotinum was detected in 1962 at a site along an abandoned railway 65 km south of Brisbane and ultimately covered a 230 square meter area plus a satellite population of two plants about 1 km away. It took 50 person-days over 18 years to eradicate this species from Australia. Examination of field reports from both cases suggests that seed dispersal and longevity of the seeds prolonged the time it took to eradicate each of these species. Mitchell, A. and M. Schmid. 2002. Case history of the eradication of fringed spider flower, Cleome rutidosperma DC. pp. 297-299. Non-native C. rutidosperma was detected in Darwin, Northern Territory in August 2000 and has not yet been eradicated from Australia. Instead of immediately eliminating these plants, as usually called for by policy, the press was first alerted and two television crew took footage of the species and its removal from the site about a week later. This footage was played on the evening news and this was followed by a two-month media campaign to alert the public. As a result, two more populations were reported and then another two populations were found (for a total of five sites in and around Darwin) by the end of the year. A sixth population was found in February 2002 and the total area occupied by all six populations was estimated to be just over 4.5 hectares. Cleome rutidosperma appears to have already been eliminated from the site where it was first detected but several years of follow-up will be required here and at the other sites to ensure the species is eradicated. There is still concern that one or more undiscovered populations remain in the area and so the search continues. The authors encourage others to resist the urge to immediately rip out a population of new invader as soon as it is discovered and to instead save it a short time for the press so that the public can be informed and urged to report any other populations as happened here. Dodd, J. and R.P. Randall. 2002. Eradication of kochia (Bassia scoparia (L.) A.J. Scott, Chenopodiaceae) in Western Australia. pp. 300-303. Kochia was intentionally introduced to Western Australia as seed in May 1990 for use in high salinity soils. By late 1991 it had been sown on 68 sites across the southwestern section of the state and it became apparent that the plant would escape to other areas and become a serious pest, particularly of wheat and perhaps conservation areas. By 1992 it had escaped at 52 of the sites where it had been sown. Although most of the sites were small by 1993 it had spread up to 5 km from some of its planting sites and was present on a total area of 3,277 hectares. Seedling densities were often high, ranging up to several thousand seedlings per square meter near parent plants. Fortunately, comprehensive information on the sites where the seed had originally been sown was supplied by the company that originally sold it, and simple wire fences had been erected around many of these sites to protect them from cattle but were coincidentally sufficient to contain these tumble-weed dispersed plants and slow their spread. A nationally-funded eradication program was initiated in 1993 and as of late 2002 the program had cost a total of about $AU 495,000 (approximately the same in $US) and required approximately 15,536 hours of labor. All known sites have been treated and nearby areas surveyed and since 2000 no kochia plants have been found on mainland Australia but the species will not be declared eradicated until five years have passed since the last live plant was detected. The introduction and spread of kochia led to major changes in the way Australia regulates plant imports and will be one the largest weed infestations (in terms of area invaded) ever eradicated. Rudman, T. and C. Goninon. 2002. Eradication case history, Hieracium pilosella L. ssp. nigrescens (Fr.) Nageli & Peter in Tasmania. pp. 304-306. Hieracium pilosella subspecies nigrescens (mouse ear hawkweed) was detected in Tasmania in January 2001 during routine botanical surveys for a road-widening project. It occupied an area totaling just 50 square meters. This area was scraped and then covered by the road widening work and all equipment used was thoroughly cleaned and inspected before being allowed to move to other sites so it is highly likely that this population was eliminated. However, H. pilosella is known to have been in some nurseries on mainland Australia so its eradication on Tasmania was not nationally funded, with the result that there was little money to survey for the presence of other populations on the island. All nurseries found offering the species for sale on the mainland have agreed to stop doing so and the authors argue that this situation makes it clear that attempts should be made to identify what they call "pre-naturalized" weeds, or species still in their lag phase but likely to naturalize and become severe pests, and that these should be designated national priority weeds and eradicated. Groves. R.H. and F.D. Panetta. 2002. Some general principles for weed eradication programs. pp. 307-310. This review successfully completed and ongoing programs to eradicate 10 plant species from Australia generates two general principles that might be used to distinguish between weeds that are appropriate candidates for eradication and those that are not: 1. Weed eradication programs will be biologically and economically feasible if the known distribution of the weed is less than 100 hectares, if it occurs at three or fewer locations, if its location sites are easily accessible and if the weed is readily detectable. 2. If the weed has a period of seed viability in the soil greater than five years and/or continues to be traded by nurseries, then that longer will be the period required for eradication. The authors believe that these principles form the basis for a decision tree for the more effective formulation of eradication programs. The Weed CRC will continue to compile eradication case histories to determine whether these generalizations hold and to glean additional lessons. |
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