For a more extensive background on the history of tamarisk biocontrol please see tamarisk biocontrol
1970s - The expense and difficulty of managing tamarisk through convention means leads scientists to begin overseas exploration for tamarisk specialist herbivores for potential use in biocontrol. Out of over 300 species of herbivores, the tamarisk leaf beetle (genus Diorhabda) is chosen as the best candidate. Extensive testing is done in the following years, both overseas and in quarantine in the US before the beetle is approved for initial field releases.
1996 - The tamarisk leaf beetle is approved for field release biocontrol methods by the USDA Animal and Plant Health Inspection Services (APHIS). Testing ensured the leafe beetle was not only effective but also would not feed on native plants or crops.
1995 - The Southwestern Willow Flycatcher (Empidonax traillii extimus) (SWFL) is listed as an endangered species by the USFWS and is reported to occasionally use tamarisk as a nesting habitat. The primary point of contention surrounding the SWFL was whether or not defoliation of tamarisk by the leaf beetle would occur during nesting times, which could potentially expose the SWFL to excessive predator and heat during its late breeding season.
2001 - Tamarisk beetles are released in 12 sites across the west.
2016 - The tamarisk leaf beetles have naturally moved through tamarisk infestations along the Colorado, Mojave, and Virgin rivers. In 2016, the tamarisk leaf beetles established in California with major defoliation in the Needles region and surrounding Lake Havasu, as well as along the Mojave River near Barstow. Another population exists further north on the Owens River, presumably established from our original research releases there in 2001. The California Alliance for Biocontrol (CATB) is established.
2016-17 - CATB has began outreach to the public, organizations, and agencies to provide information on biocontrol of tamarisk and establish a framework for future actions.In Spring 2017, the tamarisk leaf beetles continued to move and establish in California.
Look To The Future - CATB is currently identifying sites where biocontrol could be useful in controlling tamarisk, creating outreach materials and connecting with interested stakeholders, and will assist in beetle releases on approved sites. CATB has also developed a statewide monitoring protocol to monitor the natural movement of the beetles in the state and assess ecosystem responses.
If you have any questions or might be interested in participating in biocontrol in your area, please email us at TamariskAllianceCA@gmail.com