Be on the Lookout for Late-Season Insect Pests

Weekly Newspaper Article for The News-Democrat, Carrollton, KY

Despite the mild winter experienced through much of the nation, insect pest populations have been mostly below average in Kentucky.  However, as the summer season continued, weather patterns made it favorable for insets to begin migration, especially in southern states.

There have been reports of increasing numbers in the corn earworm, fall armyworm, and yellow-striped armyworm populations in various crops across the state.

Corn Earworm (University of Kentucky)

 While the corn earworm can be a pest of field corn and soybeans, this insect is also a serious pest of sweet corn and tomatoes.  The corn earworm has other names including soybean podworm, tomato fruitworm, and the cotton bollworm.  Earworms are variable in color, but they have a brown head without markings and numerous microscopic spines covering the body.  The larvae are moderately hairy and can vary from yellow, green, red, and brownish black.  Even with low numbers through much of the summer, growers need to monitor soybeans and vegetables for this pest.

Fall Armyworm; Notice the "Y" Marking on the Head (University of Kentucky)

The fall armyworm is an infrequent invader in Kentucky but can be a problem in late planted field corn.  You can recognize this brown caterpillar by an inverted light-colored "Y" on its head.  Even though there was below-normal rainfall this summer, recent rains have initiated a flush of grass growth around ditches and waterways.  The fall army worm strips these areas and moves into nearby crop fields, particularly soybeans and other grain crops.

Yellow-Striped Armyworm (University of Kentucky)

A third pest making a late-season surge is the yellow-striped armyworm.  This is a pest of many vegetables, including tomatoes, peppers, fall cole crops, and tobacco.  This caterpillar is both a leaf and fruit feeder.  The mature caterpillar is easy to recognize as it is almost black in color with two thin yellow stripes running the length of its body.

With these late season pests, growers should monitor their fields regularly and only use recommended insecticides as necessary.  Regular monitoring usually means weekly visits to the field.  With late season applications, growers need to pay close attention to required Pre-Harvest Intervals.