Blue alfalfa aphid: Economic threshold levels in southern California
Raj Sharma, Cooperative Extension, Imperial County
Vern Stern, U.C., Riverside
California Agriculture 34(2):16-17. DOI: 10.3733/ca.v034n02p16.
A deceptively low count on new regrowth may signal a population buildup and potential crop loss.An invader from the Orient, the blue alfalfa aphid, is proving far more damaging to alfalfa than the pea aphid, especially when no natural enemies are present. Fortunately, it is easy to kill with the materials registered for controlling other types of aphids on alfalfa.
Raj Sharma is Entomology Farm Advisor, Cooperative Extension, Imperial County; Vern Stern is Professor of Entomology, U.C., Riverside.