This advisory will help you determine when to scout for lesser cornstalk borers (LCB).

Lesser cornstalk borers are dark, blue-green larvae ranging from 1/2 to 3/4 inch in length with brown or purple bands around their bodies. They feed on leaves, pegs, and pods; bore into the plant near the soil line; and tunnel throughout roots and stems. Nasty bugs! They live in silken tubes or webs around the soil surface. These tubes are usually attached to the plant wherever the insect is feeding. LCB outbreaks have been associated with aflatoxin contamination in peanuts.

Outbreaks of these pests coincide with hot, dry weather as reproductive rates increase 7-fold and generation time is halved. Conditions favoring these pests can be monitored using LCB-Days. LCB-Days are a running total of hot and dry weather minus cooler and wetter weather conditions during the growing season.

We tally the LCB-Days for you. They can be interpreted as follows:

NO NEED TO SCOUT peanuts for lesser cornstalk borer. Weather patterns have been very UNFAVORABLE for the buildup of LCB numbers to damaging levels.

SCOUT FIELDS for lesser cornstalk borer. Under current conditions, increases in the numbers of lesser cornstalk borer in peanuts may reach damaging levels.

IMMEDIATLY SCOUT ALL FIELDS for lesser cornstalk borer! Weather patterns FAVOR the rapid buildup of lessor cornstalk populations to damaging levels. Apply a recommended soil insecticide when fresh feeding damage or borer (larvae) are
found at 30% of sites checked in each field.