2012 Annual Report
1a.Objectives (from AD-416):
Conduct research with USDA/BLM on weeds that are problems on BLM lands. Weeds
include saltcedar, yellowstar thistle, hoary cress, field bindweed, Canada thistle, leafy spurge and the knapweeds. The search for new biological control agents will be conducted by USDA/ARS/EBCL. Research on saltcedar biological control will be conducted by USDA/ARS Sino-American Biological Control Lab-China and by Exotic and Invasive Weeds Research Lab-Albany, CA. Insects cleared for use in U.S. will be released and/or evaluated by ARS, Sidney, MT.
1b.Approach (from AD-416):
Exploration will be conducted in Europe, Eurasia, and China for insects and
pathogens which show potential as control agents for priority noxious weeds. Once
identified, the agents will be tested for host-specificity and efficacy. Tests on
saltcedar and yellowstar thistle insects may be conducted in quarantine in Albany, CA. This is a long-term process, extending over three to six years for new agents. Once tests are completed on a Technical Advisory Group (TAG) list of plants, a report of the test results will be submitted to APHIS/PPQ and TAG. Agents approved for quarantine and/or release via quarantine will be collected and sent to the appropriate quarantine facility for processing. Cleared biological control agents will be released on BLM administered lands by ARS, Sidney, MT. Post-release monitoring for establishment and impact on the targeted weed species will follow these releases. All programmatic changes must be approved in advance by NPS.
We monitored saltcedar attack by biological control agents in WY, but found the tamarisk beetle present only at barely detectable levels. We still have no known established beetle populations in MT, and are not allowed to import beetles due to APHIS permit revocations. We are initiating new beetle releases in WY in August. The hoary cress weevil was imported to quarantine and is awaiting rearing for hybridization studies.
Japanese, Giant and Bohemian knotweed species are highly invasive in North America, especially in the Pacific Northwest USA and western Canada. These species hybridize and are thus difficult to distinguish with morphology, and biological control agents currently being developed attack each species, and certain hybrids, with different levels of efficacy. ARS researchers at Sidney, MT were asked by Oregon State University, University of Idaho, and Agriculture and AgriFood Canada to use molecular tools on over 900 plants from 132 locations in nine states and provinces to determine identity of local invasions and distribution of the species across western North America. This information will be used to ensure that representative knotweed genotypes are adequately screened in biological control testing, and that biological control agents are distributed only in regions where they will be effective.
Progress for this work was delivered as published papers and presentations at the January 2012 MT Weed Control Association Meeting.