Abstract: Bio-control Activities and Consortium Makeup and Future Direction

Saltcedar is probably the most destructive exotic, invasive weed of western riparian areas. It rapidly excludes desirable native vegetation, especially following wildfires or floods, in saline soils and in overgrazed areas; interacts synergistically with altered hydrologic cycles below dams, droughts, overgrazing, and with some control methods to increase its own competitive advantage over native plants. It dries up desert springs and small streams, alters stream geomorphology and water quality, and increases soil salinity, all of which seriously degrade wildlife habitat including that of many sensitive species of birds, fish and other animals and plants. It interferes with recreational usage of parks and natural areas, and is a major water user that put it in direct conflict with agriculture and municipalities. To help combat this exotic pest plant, the United States Department of Agriculture developed a biological control research and implementation effort that is now well under way and showing significant success. Biological control provides an environmentally compatible alternative method of control. Beetles (Diorhabda elongata) from China, Crete and other Eurasian locations have been tested by USDA-ARS scientists in Albany, CA and Temple, TX for efficacy and safety and have been permitted for release by both the US Fish and Wildlife Service and USDA-APHIS. Releases were initially made in six western states in limited release areas where cage studies verified the efficacy of these insect natural enemies. Open field releases have further verified their effectiveness in multiple field sites. For example, release of 1300 beetles in the summer of 2001 increase to millions of beetles in two seasons so that over 400 acres of saltcedar was totally defoliated in research sites in Nevada. Similar results have been seen in Colorado, Utah, and Wyoming. Additional research is being conducted to provide beetles adapted for more southern areas. These beetles should be affective in states such as California, New Mexico and Texas. This effort was planned and implemented through a effort with many local, state and federal groups. A Saltcedar Biological Control Consortium was established and used to provide the USDA and others with guidance in implementing this effort. Details of the biological control program and its management via the Saltcedar Biological Control Consortium will be discussed.

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