The brown marmorated stink bug (BMSB) has now moved into almonds. The feared pest was first reported in California in 2002, and a large find was announced in Sacramento, in 2013.
Since then, it’s been wait-and-see for fruit growers in the state as it seemed like only a matter of time before the hitchhiking bug would discover the state’s abundant variety of fruit, including peaches, a particular favourite of the pest. Its movement each year inched closer and closer to agricultural production.
Well, that time has come as BMSB was found by a peach grower in his home near a peach orchard in fall 2015, and subsequent seasonal surveys in 2016 in peach orchards confirmed the abundance of BMSB in the Northern San Joaquin Valley. This year BMSB has been reported in almond orchards as well.
“The first finding was in 2016 in peaches and this year in almonds we found them around mid-June,” says Jhalendra Rijal, University of California Cooperative Extension Area IPM Advisor for San Joaquin, Stanislaus, and Merced counties. “We found adult, nymph, and egg masses in almond trees in one orchard. We also caught several adults and one nymph from a second almond orchard that we are monitoring this year.”
What can be done
Rijal suggests growers notify their Cooperative Extension advisors of whatever findings you might have, obviously if you suspect damage from BMSB. Growers in counties where stink bugs have been found — especially in the Northern San Joaquin Valley — should be monitoring and trapping for BMSB the entire growing season as Rijal and his team are still learning how many generations of the pest will occur in one growing season in California.
He suggests growers use BMSB-specific lures in black pyramid traps and/
or in sticky panel traps as part of the monitoring strategy. While BMSB looks similar to other stink bugs, there are a few tell-tale markings on BMSBs including white bands on antennae and legs as well as dark and light bands on the margins of the abdomen.
Shoulders of BMSBs are more rounded than its lookalike stink bug counterparts. The presence of the white bands on antennae and legs are the best ways to distinguish BMSB nymphs from other nymphs.
