A look at beetle-occupied tamarisk sites 11-13 years after initial occupancy to determine long-term vegetative community response. Study found that Tamarix cover across sites initially declined an average of ca. 50% in response to the beetle, but then recovered. Changes in the associated plant community were small but supported common management goals, including a 47% average increase in cover of a native shrub (Salix exigua), and no secondary invasions by other non-native plants.

Stahlke et al. developed a reference genome for tamarisk beetles (Diorhabda spp.) and reference panel of all four introduced parental species to monitor range expansion and hybridization across North America. They found a substantial genetic bottleneck among D. carinulata in N. America, although populations continue to establish and spread, possibly due to aggregation behavior. Among hybrids, they found that D. carinata, D. elongata, and D. sublineata hybridize in the field, especially in eastern New Mexico, with D. carinata × D.

The leaf beetle Diorhabda elongata Brullé subspecies deserticola Chen, collected in northwestern China, has been released in the western United States to control tamarisk (Tamarix spp.). While beetle establishment and saltcedar defoliation have been noted at northern study sites, this species has not established at latitudes south of the 38th parallel.

A presentation by Dan Bean at the 2020 RiversEdge West Conference about new knowledge on aggregation phermones, phenology, and genomics. 

Remote sensing methods are commonly used to monitor the invasive riparian shrub tamarisk (Tamarix spp.) and its response to the northern tamarisk beetle (Diorhabda carinulata), a specialized herbivore introduced as a biocontrol agent to control tamarisk in the Southwest USA in 2001.

A 2006 review of the saltcedar (Tamarix) biocontrol program. 

 

DeLoach, C.J., Milbrath, L.R., Carruthers, R., Knutson, A.E., Nibling, F., Eberts, D., Thompson, D.C., Kazmer, D.J., Dudley, T.L., Bean, D.W. and Knight, J.B., 2006. Overview of saltcedar biological control. In Monitoring science and technology symposium: unifying knowledge for sustainability in the Western Hemisphere. Proceedings RMRS-P-42CD. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fort Collins, Colorado (pp. 92-99).

Henry et al. 2018

In this study, we employ multi-scale analysis (Moran’s Eigenvector Maps) to better understand the variation in tree canopy exposed to defoliation by a biocontrol beetle (Diorhabda spp.).