Location: European Biological Control Laboratory
Project Number: 0212-22000-028-00-D
Project Type: In-House Appropriated
Start Date: Dec 2, 2015
End Date: Dec 1, 2020
Objective 1: Explore for natural enemies, including arthropods and microorganisms, of invasive weeds identified as high priority targets by the ARS Office of National Programs, performing collections, importations and exportations in compliance with local and international regulations. High priority pests include hoary cress, swallow-worts, thistle species, giant reed, tree of heaven, French broom, and medusahead grass. Objective 2: Perform taxonomic, population genetic, and phylogeographic studies as necessary to support the successful development of biological control agents for invasive weeds. Objective 3: Identify the biological and physical parameters that affect the efficacy and safety of potential agents, including climatic conditions, host specificity, effective rearing conditions, and how interactions that occur between a target weed (e.g. hoary cress) and multiple natural enemies (e.g., a root gall weevil and a root pathogen) enhance or inhibit biocontrol.
The goal of the proposed research is to improve management of several important, invasive alien weeds of the contiguous United States. The Bureau of Land Management estimates that over 4,600 acres of western rangelands are lost to the spread of invasive weeds each day. Successful invaders usually lack natural enemies, which control them in their native ranges. Classical biological control is a highly cost-effective, sustainable, environmentally-sound method of controlling exotic weeds over large areas. This method requires research aimed at understanding the basic biology and ecology of target weeds and their interactions with the environment and natural enemies. Genetic characterization of target weeds in their native and adventive ranges can identify regions of origin of invasive populations and help to understand the invasion process. Foreign exploration in the region of origin provides candidate biological control agents such as insects and mites for evaluation. Host specificity and potential effectiveness of candidates will be evaluated in field and laboratory studies. Experiments will also examine the evolutionary, ecological, and physiological aspects of plant-insect interactions relevant to weed biological control. Research on yellow starthistle, hoary cress, giant reed, medusahead, and French broom will continue, and additional weeds will be targeted in response to stakeholder demand and available resources. EBCL plays a key role providing research and prospective agents to federal and state cooperators necessary for the successful control of target weeds. The research proposed here is critical to achieving ecologically rational, sustainable management of some of the most important invasive weeds in the United States.