Long, hot summer days paired with a dry climate means one thing for grape growers: insects. These small pests can create big problems for a vineyard when the climate is right. Being prepared with reliable crop protection tools is essential for growers to protect their crop during this critical stage of grape development.

One of the most destructive grape pests found in California vineyards are mealybugs. Small but mighty, the mealybug can reduce yield by up to 40 percent. Vine mealybugs produce a substance called honeydew that drops onto the bunches and other vine parts. A large quantity of the waxlike substance can lead to black sooty mold infestations on the grape crop.

As temperatures rise in the springtime, vine mealybug populations increase and become more visible as they move from the roots or trunk to the cordons and canopy, according to UC IPM. By late spring and summer, vine mealybugs are found on all parts of the vine. Being proactive with the application of an insecticide can help lower populations in infested areas.

Another pest grape growers should be wary of is the leafhopper. Most commonly found in the San Joaquin, Sacramento and North Coast valleys of California, the leafhopper can wreak havoc on a vineyard in the summer months. Nymphs and adults suck the contents of the leaf’s cells which causes pale yellow spots. While vines can tolerate fairly high populations of the pest, severe infestations can result in leaf drop, leading to sunburned fruit and delayed ripening. In young or stressed vines, this can reduce shoot growth the following season.

Products such as ASSAIL^® and BIFENTURE^® EC Insecticides offer protection designed specifically to ward off harmful insects including the mealybug, leafhopper and other key grape pests. These insecticides work together with the vineyard’s natural ecosystem to keep grape leaves pest-free.

ASSAIL (IRAC 4A) is an effective broad-spectrum option when mealybug, leafhopper, thrips, aphid and/or whitefly are what you are seeking to control. With Lorsban moving out of the California market, ASSAIL is a perfect addition to your mealybug program. ASSAIL’s translaminar activity provides weeks of residual control to your insect management program.   

BIFENTURE (IRAC 3A) is one of the most widely used insecticide/miticide products on the market — a second-generation pyrethroid that offers a level of quality, consistency and effectiveness at an economical cost per acre. With its excellent contact and residual activity, BIFENTURE controls a wide spectrum of insects and mites on grapes, including cutworms, leafhoppers, grape berry moth and more.

Whatever pest your vineyard is experiencing, you can count on UPL for a complete line of reliable grape protection and a staff dedicated to keeping your vineyard going strong. For more information, contact your local retailer or visit www.upl-ltd.com/us.