Forages & Grains
Volume 64 Number 15 Date 08/08/2019
POTATO LEAFHOPPER - Surveys continue to yield above-threshold counts of 2.0 or more leafhoppers per sweep. High populations were recorded in about one-half of the fields sampled last month, and reports indicate that treatments were applied to many alfalfa acres. Nymphs are still common in sweep nets, and weekly monitoring of the third alfalfa crop throughout August is recommended.
GRASSHOPPER - Late-season grasshopper activity is escalating in alfalfa and other crops. Defoliation has become pronounced along field margins since mid-July. Grasshopper damage to forage crops can be serious at this time of year, especially in new alfalfa seedings and when dry weather slows plant regrowth after harvest. Chemical intervention is not necessary unless populations reach 20 grasshoppers per square yard at the margins or eight per square yard within an alfalfa field.
-- Krista Hamilton, DATCP Entomologist