Pest Management Program

County Agricultural Commissioners are charged with the responsibility of managing nuisance pests of agriculture and human health.  Many of these pests are introduced species that have become established despite the best efforts of agricultural commissioners and CDFA to eradicate them.  One insect pest example is the Glassy-winged Sharpshooter that is under intensive control efforts in several southern counties, while eradication efforts continue in counties farther north.  Merced County assists with the management of aquatic weed species such as Water Hyacinth.  Our Department provides assistance to agriculture in controlling vertebrate pests through manufacturing and the sale of rodent baits (Chlorophacinone, Diphancinone and Zinc Phosphide) and sale of gas cartridges manufactured by USDA.

Management of larger vertebrate pest species such as coyote, skunk and beaver is conducted under a Merced County contact with USDA-APHIS - Wildlife Services.  The Agricultural Commissioner provides indirect oversight of this work.

Biological Pest Management (Biocontrol) in California began in 1888 with the introduction of the Vedalia Ladybettle to control Cottony Cushion Scale on citrus.  CDFA, the University of California and County Agricultural Commissioners have been leaders in Biocontrol for over 100 years.  In Merced County, Biocontrol agents have been successfully introduced and established for insect pests including Ash Whitefly, Grapeleaf Skeletonizer (3 organisms), and Red Gum Lerp Psyllid.  Successful introductions for weed pests include Yellowstar Thistle (5 organisms), Russian Thistle (2 organisms), Puncture Vine (2 organisms), Italian Thistle, and Klamath Weed.