By the Chemtura AgroSolutions team of experts
As raisin grape harvest picks up steam in the Central Valley, grape growers are reminded to keep leafhoppers top of mind.
“We’ve had a tough season for mites this year, but we also need to keep an eye out for leafhoppers over the next couple of weeks,” suggests Nathan Ostley, PCA with Kerman Ag Resources in Madera, California.
Keep in mind treatment thresholds vary according to leafhopper generation, the variety and type of grapes you grow, canopy size, your location and the degree of parasitism.
“Harvest is about a week to 10 days ahead of last year, so we may be able to manage around them, but growers always need to be on the lookout for leafhoppers,” he adds.
Click here for more hints on leafhopper monitoring and control.
This is also a good time to monitor diseases that can impact vine health, like Botrytis bunch rot. A fungicide application may also be warranted if a major rain is expected late in the season when grapes are nearly mature, note Integrated Pest Management experts at the University of California.
Viticure® is a systemic sterol inhibitor fungicide that’s labeled to suppress black rot and Botrytis bunch rot. It works by inhibiting development of cell walls in the target organism, which, without cell walls, cannot survive. Viticure has a short seven-day preharvest interval, making it a good choice for treatments during this time of the season.
Be sure to visit with your PCA or Chemtura AgroSolutions representative for additional ways to enhance your control program and ensure a successful harvest:
• 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