By the Chemtura AgroSolutions team of experts
It’s that time again, time to be on the lookout for damaging web-spinning mites — like the Pacific spider mite: Tetranychus pacificus, Willamette spider mite: Eotetranychus willamettei, and the two-spotted spider mite: Tetranychus urticae — that take a bite out of vineyard profits.
Pacific spider mites and Willamette spider mites are generally the most common of these pests.
To help identify which mite is bugging your vineyard evaluate damage patterns, since each species impacts grapes differently, say Integrated Pest Management experts at the University of California.
For example, Pacific spider mite damage begins as yellow spots. As damage progresses dead (necrotic) areas appear on the leaves. High populations can render the leaves unfunctional with leaf burning and bronzing and profuse amounts of webbing. Damage is worse along the shoulder and tops of the vine canopies.
Meanwhile, the Willamette spider mite is often considered an early-season mite. It prefers the cooler parts of the plant and is found mostly in the shady parts of the vine. Its feeding causes foliage to turn yellowish bronze, but usually no burn occurs unless vines are weak. In red varieties, infested leaves may turn reddish.
The key to controlling undesirable mites while maintaining beneficial insect populations is to use the right chemistry at the right time.
Start off the season with Acramite® 50WS, which delivers good knockdown mite control without affecting beneficials. Acramite eliminates the majority of undesirable mites, giving beneficial insects a head start in keeping mite populations in check. Plus, its unique carbazate chemistry also makes Acramite an excellent rotational miticide for resistance management.
And remember, always read and follow label directions.
Be sure to visit with your PCA or Chemtura AgroSolutions representative for additional ways to enhance your control program and ensure a successful season:
• Mike Ansolabehere, Southern San Joaquin Valley: (661) 304-3023; email Mike.Ansolabehere@Chemtura.com
• Matt Loftus, Central San Joaquin Valley: (559) 960-1112; email Matthew.Loftus@Chemtura.com
• Eric Leer, North Central California: (209) 531-6478; email