2006 Annual Report 1.What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? Why does it matter? Invasive plants are a serious problem. An estimated 4600 acres of natural areas are lost to invasive plant species every day. Thousands of aquatic habitats are also infested with invasive weeds. Exotic plants displace desirable plants that provide forage for livestock and wildlife, eliminate critical habitats, and affect other resources such as natural and wildland ecosystems, important for threatened and endangered species as well as agricultural production. It has been estimated that non-indigenous weeds cost the U. S. between $3.6 and $5.4 billion annually. Impacts from aquatic and riparian invasive weeds alone have been historically estimated to be $150 to $200 million annually; however recent (2003) estimates place the benefits of controlling these weeds at $500 million to more than $1 billion annually. Results of studies will contribute to solutions to problems in areas of national concern that are impacted by invasive weeds including: San Francisco Bay-Delta, Lake Tahoe/ Tahoe Basin, western irrigation systems, riparian/floodplain habitats such as the Laguna de Santa Rosa-Russian River Basin, CA, and rangelands. Development of truly integrated management paradigms also have wide-spread benefits since they will encompass many sites and target species that cause economic losses in the US as well as world-wide. By providing a basis for decreasing dependence on, and lowering the amount of herbicides needed, results of this work will contribute to the national goals to improve water quality and preservation of sensitive habitats (hence protect and enhance species diversity). Results also assist federal and state regulatory agencies such as US Bureau of Reclamation, APHIS, NMFS (NOAA-Fisheries), Calif. Dept. of Food and Agriculture, Calif. Dept. of Boating and Waterways, Calif. Dept. of Fish and Game, USFWS as well as local weed-management districts and flood control districts. This project has four main objectives:. 1)Improve our biological understanding and enhance our ability to manage important invasive weeds in western aquatic and riparian ecosystems.;. 2)Develop integrated vegetation management strategies to restore ecological structure and function to western aquatic and riparian ecosystems; and. 3)Determine the most ecologically sound and cost effective methods for managing aquatic and riparian weeds using herbicides and/or natural products; and. 4)Develop rapid response strategies and methods for aquatic plant infestations that pose serious economic and environmental threats. The project addresses objectives of NP 304-Crop Protection and Quarantine. It also addresses components of NP 205 (Rangeland, Pasture and Forages) and NP 201 (Water Quality and Management). Within the 304 Program this CRIS targets all of the following Weed Science components: Investigations of pest biology (Weed Biology and Ecology); Development of biologically based pest control technologies (Biological Control of Weeds); Improved herbicide efficiency use of natural products (Chemical Control of Weeds); Integration of management methods (Weed Management Systems). 2.List by year the currently approved milestones (indicators of research progress) Year 1 (FY 05) 1. Water Primrose: Site selection; Develop life cycle model; Measure plant and insect community characteristics; Establish exp. seed banks. 2. Egeria: Initiate sampling; establish pore-water sampling sites. 3. Egeria: Site selection; Deploy resin bags, collect plant samples, measure nutrients. 4. Giant Reed: Set up experiment; Initiate shoot destruction. Measure plant characteristics. 5. Water Primrose/Native Species Restoration: Site Selection; Community Characterization; Collect seed bank cores – initiate greenhouse study. 6. Egeria and Eurasian watermilfoil: Site selection; community characterization; establish mesocosm cultures; site selection for sediment /propagules; begin surveys for egeria insects and for E. lecontei. 7. Restoration Strategies/Giant Reed Infested Habitats: Site selection. Establish plots; collect baseline pretreatment data; apply treatments. 8. Fluridone Use: Establish cultures; begin first applications. 9. Penoxsulam and Dilute Acetic Acid Use: Site selection. Establish plots; collect pretreatment data; apply acetic acid or penoxsulam. 10. Watermilfoil Growth: Site selection; Deploy data loggers, collect plant samples for standing crop. 11. Curlyleaf Pondweed, Water Chestnut, and Hydrilla: Obtain permits and establish cultures of target weed; begin treatments on hydrilla; site selection for dredging. Year 2 (FY 06) 1. Water Primrose: Tag Plants; Demographic measurements; Analyze plant, insect, and habitat data. 2. Egeria: Complete sampling, complete CHN analysis; begin pore water/dialysis sampling. 3. Egeria: Set up growth experiment; continue field measurements. 4. Giant Reed: Post-1st year treatment measurements; continue treatments. 5. Water Primrose/Native Species Restoration: Seed bank response experiment; evaluate weed response to environment manipulation. 6. Egeria and Eurasian watermilfoil: Conduct sampling for insect communities; begin mesocosm studies; initiate sediment/propagule evaluations; continue surveys for egeria insects; complete surveys E. lecontei; begin host specificity testing on egeria insects. 7. Restoration Strategies/Giant Reed Infested Habitats: Post-1st year treatment measurements; continue treatments. 8. Fluridone Use: Continue establishment of cultures; continue applications. 9. Penoxsulam and Dilute Acetic Acid Use: Post-1st year treatment measurements; continue treatments. 10. Watermilfoil Growth: Site selection; Deploy data loggers, collect plant samples for standing crop. 11. Curlyleaf Pondweed, Water Chestnut, and Hydrilla: Continue hydrilla treatments; begin herbicide treatments and assess effects on water chestnut and curlyleaf pondweed; conduct pre/post dredge assessments. Year 3 (FY 07) 1. Water Primrose: Demographic measurements; Multivariate analysis plant and insect community data; prepare publication. 2. Egeria: Complete pore water/dialysis sampling; summarize/data analysis of CHN. 3. Egeria: Repeat growth experiment; continue field measurements. Derive predictive equations. 4. Giant Reed: Post-2nd year treatment measurements; continue treatments. 5. Water Primrose/Native Species Restoration: Continue and repeat experiments to identify ecological process remediation for restoration. 6. Egeria and Eurasian watermilfoil: Continue community sampling; continue mesocosm and native propagule bank studies; continue host-specificity testing on egeria insects. 7. Restoration Strategies/Giant Reed Infested Habitats: Post-2nd year treatment measurements; continue treatments. 8. Fluridone Use: Continue establishment of cultures; continue applications. 9. Penoxsulam and Dilute Acetic Acid Use: Post-2nd year treatment measurements; continue treatments. 10. Watermilfoil Growth: Site selection; Deploy data loggers, collect plant samples for standing crop. 11. Curlyleaf Pondweed, Water Chestnut, and Hydrilla: Data analysis for treatments; prepare publication; continue second tier of herbicides treatments; continue dredge assessments. Year 4 (FY 08) 1. Water Primrose: Demographic measurements; Life Table Analysis; Matrix model development. 2. Egeria: Complete pore water data analysis; prepare publications on phenology and pore water interactions. 3. Egeria: Repeat growth experiment; select sites to test equation predictions. 4. Giant Reed: Post-3rd year treatment measurements; continue treatments. 5. Water Primrose/Native Species Restoration: Conduct preliminary community assembly tests for weed mgmt/restoration. 6. Egeria and Eurasian watermilfoil: Complete community analysis; complete analysis of mesocosms and propagules bank studies; introduce egeria insects to quarantine in US; continue host testing. 7. Restoration Strategies/Giant Reed Infested Habitats: Post-3rd year treatment measurements; continue treatments. 8. Fluridone Use: Site selection; applications of proposed optimal treatments for egeria control. 9. Penoxsulam and Dilute Acetic Acid Use: Data analysis;prepare publication. 10. Watermilfoil Growth: Site selection; Deploy data loggers, collect plant samples for standing crop. 11. Curlyleaf Pondweed, Water Chestnut, and Hydrilla: Prepare publications and recommendations for hydrilla and curlyleaf pondweed. Year 5 (FY 09) 1. Water Primrose: Data analysis; prepare publication. 2. Egeria: Provide recommendations to Boating and Waterways on optimizing egeria management. 3. Egeria: Data analysis; prepare publication. 4. Giant Reed: Data analysis; prepare publication. 5. Water Primrose/Native Species Restoration: Data analysis; prepare publication. 6. Egeria and Eurasian watermilfoil: Data analysis; prepare publication and prepare proposal for review for approval to release egeria insects; prepare recommendations for restoration actions in egeria-managed sites. 7. Restoration Strategies/Giant Reed Infested Habitats: Data analysis; prepare publication; prepare publication and prepare proposal 8. Fluridone Use: Analysis of field applications; prepare and submit publication; prepare final recommendations to the state egeria control program. 9. Penoxsulam and Dilute Acetic Acid Use: Publish findings. 10. Watermilfoil Growth: Data analysis; prepare publication. 11. Curlyleaf Pondweed, Water Chestnut, and Hydrilla: Data analysis; prepare publication for water chestnut. 4a.List the single most significant research accomplishment during FY 2006. Caulerpa eradication from California NP 304, Related Action Plan Component VII, Weed Biology and Ecology, 14C: Early Detection and Rapid Response. Caulerpa taxifolia was eradicated from California through a cooperative interagency effort. This invasive marine algal, spread to over 30,000 acres in the Mediterranean Sea from 1985 to 1999, and in 2000, the first two US introductions of this species were discovered in California. These infestations threatened over 600 miles of western coastal subtidal habitat. ARS scientists at the Davis worksite of the Exotic and Invasive Weed Research Unit conducted research and provided technology transfer as part of a multi-agency eradication effort during the past 5 years. This work was essential in development and implementation of methods for effective eradication of C. taxifolia which provided quantitative evaluation of eradication efficacy and helped establish scientifically based criteria for determining how and when eradication could be achieved. Results have culminated in a final declaration of eradication by the California Department of Fish and Game (July 12, 2006) and is sure to have saved the State of California millions of dollars by reducing damage and control costs. 4b.List other significant research accomplishment(s), if any. Biology and Growth or Giant Reed: NP 304, Related Action Plan Component 14E, Growth, Development and Competition. These accomplishments directly address gaps in these problem areas for two important invasive weeds. Giant reed (Arundo donax L.) is a tall perennial reed classified as an emergent aquatic plant. In California, it has invaded riparian zones, where it acts as a transformer species. Scientists at the Davis worksite of the Exotic and Invasive Weeds Research Unit developed a model based on an equation for estimating Arundo donax shoot dry weight from shoot length that was as effective at explaining a high proportion of total variation in shoot dry weight (R2 = 0.90) as more complicated equations containing additional morphometric parameters. The model provided accurate estimates of dry weight for shoots ranging from 0.3 to 7.06 m height when tested against two independent datasets. The model provides aboveground biomass estimates from stem counts and heights more rapidly than direct harvest methods and is useful to a variety of field personnel in assessing efficacy of various control methods. Biology and Management of Invasive Water Primrose: NP 304, Related Action Plan Component 14E, Growth, Development and Competition. These accomplishments directly address gaps in these problem areas for two important invasive weeds. Water primrose (Ludwigia spp.) from South America is aggressively invading canals, wetland and riparian habitats throughout California and in doing so, threaten federal water project deliveries. Ludwigia forms dense floating mats that displace native vegetation and fill open water habitat, and thus interfere with mosquito control and reduced vector control is further thought to increase the possibility West Nile Virus transmission and thus Ludwigia management of significant importance to a variety of aquatic resource managers. To provide basic information to aquatic system managers, scientists at the Davis and Albany, CA worksites of the Exotic and Invasive Weeds Research Unit conducted mesocosm experiments to understand Ludwigia growth responses to hydrology, have established longer term research to determine mechanisms influencing establishment, colonization/ spread, and have assessed the aquatic invertebrate fauna (including mosquitoes) in infested and noninfested areas. Taxonomic identity of the invasive plant species is confusing as morphology varies with environmental conditions, so ARS scientists surveyed the morphological variation of invasive populations throughout California and discovered that many populations had been mis-identified by local managers. Chromosome studies were then conducted to clarify species identity in support of local management programs and biological control research in California and Argentina. These studies will provide information on long-term management and restoration within the watershed and will assist managers with faced with water primrose invasions in the Sacramento Valley, Sacramento-San Joaquin Delta, San Diego and Ventura River Watersheds. Management of Invasive Aquatic Weeds: NP 304, Related Action Plan Component VII- Weed Biology and Ecology, 14C: Early Detection and Rapid Response. This accomplishment directly contributes to both practical approaches for rapid responses (logistics) but also to the broader strategies of organization and functions of rapid response efforts. Small scale field mesocosms and outdoor cultures were used by ARS scientists at the Davis worksite of the Exotic and Invasive Weed Research Unit to assess efficacy of a new systemic herbicide, penoxsulam, against Egeria densa, Myriophyllum spicaum, M. aquaticum. Simulated drawdown applications were used to determine potential for use of penoxsulam for control of Potamogeton nodosus and Stuckenia pectinatus in irrigations canals. Results suggest that rates of 150 g/ha on exposed canals soils may provide 45 day control. These results will be useful to various aquatic system managers and the University of California Extension Service in making and implementing new control recommendations for these aquatic weed species. 4c.List significant activities that support special target populations. None 4d.Progress report. None. 5.Describe the major accomplishments to date and their predicted or actual impact. Models for growth and development in Arundo donax have been developed, which will help provide optimal timing and methods for mechanical or herbicidal control, as well as identify key targets for potential biological control agents. (NP Components 14/VII (Weed biology and ecology), and 18/IX(Biological control of weeds). Developments of essential components of successful rapid response leading to full eradication of an invasive algal have provided guidance for similar programs (NP 304, Related Action Plan Component VII- Weed Biology and Ecology, 14C: Early Detection and Rapid Response. This accomplishment directly contributes to both practical approaches for rapid responses logistics, but also to the broader strategies of organization and functions of rapid response efforts. Initiation of long-term community structure and ecological studies on water primrose will provide a basis for development of management plans, including potential for biological control. (NP 304, Components 14/VII Weed Biology and Ecology, and 18/ IX, Biological Control of Weeds. Research on dissipation of key aquatic herbicides has led to their safe and effective uses and have helped provide critically important tools for management of submersed aquatic invasive plants in the US and in particular in the Sacramento - San Joaquin Delta, (NP 304, Component 16/IIIV, Chemical Control of Weeds, and 10/V, Pest Control Strategies. 6.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? Provided scientific information, data, and technical support to state and federal agencies, including California Department of Agriculture (CDFA), California Department of Boating and Waterways (BWW), California Department of Fish and Game, US Fish & Wildlife Service, and US Bureau of Reclamation that seek to manage exotic and invasive weeds in the Sacramento-San Joaquin Delta, and the Russian River Watershed. We participated as members of the Steering Committee of the Southern California Caulerpa Action Team (SCCAT) and provided expertise on the eradication program and developed criteria that were essential for determining the success of eradication. We served as a technical advisory to the California Bay-Delta Authority’s Ecosystem Restoration Program. We provided examples of on-going research to the public at an annual Picnic Day on the UCD campus attended by 40,000 people. Our educational displays included hands on activities to show how aquatic plants are dispersed via boating activities. We participated in an annual "Weed Day" educational event at the UCD Campus during which we presented research findings to over 100 weed control practitioners. 7.List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). We presented four papers at the Western Aquatic Plant Management Society conference in San Diego, three papers at the Aquatic Plant Management Society conference in San Antonio, one paper at the Ecological Society of America meeting in Montreal, a poster at the California Invasive Plant Species Symposium in Chico, California, one paper at the International Conference on Aquatic Invasive Species in Miami, Florida, and one paper at the California Lake Management Society. We participated in bi-weekly meetings of the UC Davis Weed Science Group and presented research results. We provided lectures and contributed to workshops on weed control and invasive species for a variety of stakeholders including pest control advisors, farm advisors, county/city park managers, ranchers and farmers. Most of the advice and suggested technology was accepted and is in use. We provided five lectures on aquatic weed control to professional pest management organizations (Pesticide Applicator Professional Association, California Association of Pest Control Advisors,). We provided guest lectures on invasive water primrose to marsh managers throughout California. We participated in a National Public Radio broadcast about water primrose invasions and integrated weed management as a component of ecological restoration. We provided expertise on two Sacramento-San Joaquin Delta restoration projects (Dutch Slough and N. Delta). We presented one paper and chaired a breakout session at an Aquatic Weed Research Workshop in San Diego, California. Review Publications Spencer, D.F., Ksander, G.G., Donovan, M., Liow, P., Chan, W.K., Greenfield, B.K., Shonkoff, S., Andrews, S. 2006. Evaluation of waterhyacinth survival and growth following cutting. Journal of Aquatic Plant Management. 44:50-59. Spencer, D.F., Liow, P., Chan, W., Ksander, G.G. 2006. Estimating arundo donax l. shoot biomass. Aquatic Botany. 84:272-276. Anderson, L.W. 2005. California's reaction to caulerpa taxifolia: a model for invasive species rapid response. Biological Invasions. 7:1003-1016.