What is in this article?:
- Invasive pests severely impact California agriculture
- Invasive pest challenges continue
- Ratings for pest status
- Many exotic and invasive pests are of major concern in California. The glassy‐winged sharpshooter (an insect) and purple loosestrife (a weed) are two invasive species that are established in some areas but still threaten to invade other areas.
- Invasive species of concern to California’s grape industry include European grapevine moth (EGVM) and light brown apple moth (LBAM), have not yet established themselves in all grape growing areas, but have already been costly to the state and the grape industry.
Invasive pest challenges continue
California’s grape industry continues to be challenged by new pest introductions. Light brown apple (LBAM) and European grapevine (EGVM) moths are the most recent insect introductions impacting California grape growers.
Although growers have spent money on pesticide applications to manage isolated populations, grape growers and their industries have mostly been affected by the pest rating that identifies them as quarantine pests.
Growers in quarantine areas have worked closely with the USDA, CDFA and the local County Ag Commissioners to comply with the mandated programs so fruit can continue to be harvested and moved to their respective markets.
One pest of most concern for California agriculture and the states residents is the brown marmorated stink bug (BMSB) now found in 33 states. Although not established in California, it has been documented on several occasions in different parts of the state including Los Angeles and Solano counties. BMBS has the ability to fly, which helps it move to new locations outside of infested sites.
However, its primary movement into new areas has been through human activity by hitchhiking in vehicles, equipment and anything else that gets shipped over long distances. Native to Asia, it is thought that BMSB arrived in packing crates shipped to the Eastern United States. It has a large host range that includes grapes and many of the fruits and vegetables grown in California.
Damage can be substantial when BMSB populations are not identified early and managed appropriately.
Apple growers in the Mid‐Atlantic states have reported losses of $37 million representing 18 percent of their fresh apple market.
In addition to physical fruit damage, growers and wineries would also have to contend with the off flavors produced by BMSB that gets crushed for wine or juice.
Homeowners in the Mid‐Atlantic states also reported large BMBS populations taking refuge in their homes during the winter months and becoming a nuisance when the insects are frightened or smashed, releasing an odor — hence the name “stink bug”. It is important for growers and residents to take odd or unique looking pests to their local university advisor, ag commissioner or state ag department entomologist for proper identification. Identifying invasive pests early is key to protecting California’s billion dollar agricultural industry.