Last week I had the opportunity to spend some time in the field with Extension Entomologist Roy Parker. One of the field activities included estimating damage resulting from corn earworm activity. As might be expected the pest was not hard to find.

The field exercise reminded me how difficult it is to grow sweet corn in the home garden without suffering some losses from the corn earworm.

The home gardener is not alone in battling this pest, the corn earworm feeds on many plants. In the United States, the earworm is also a destructive pest of cotton and tomatoes.

In the cotton field the corn earworm is referred to as the cotton bollworm and when it feeds on tomatoes it is commonly called the tomato fruitworm.

Adult corn earworm moths vary in color and markings, but the forewings are usually light yellow to yellowish brown, with dark irregular lines and a dark area near the tip. The hind wings are white with irregular dark markings near the border.

Adult moths are most active at night. During their 10 to 14-day life span females are capable of laying 450 to 2,000 eggs. Eggs hatch in 2 to 5 days and the larval or caterpillar stage lasts about 2 to 3 weeks before they pupate.

The larvae vary in color from pale green to dark brown, with alternating light and dark longitudinal brown or orange stripes running the length of the body.

The head is dark yellow or reddish orange. It is the larvae that seemingly eat more corn than the gardener gets to enjoy each year. Even before the ears develop, corn earworms feed in the whorl of leaves and their presence will often go undetected until damaged leaves unfold exposing large ragged holes.

Eggs of later generations are laid on the corn silks and the emerging caterpillars feed on the silks and then on the ears from the tips downward.

The Aggie Horticulture web site, vegetable IPM page, list numerous biological and chemical controls for the corn earworm. Chemical controls are spray or dust formulations with carbaryl, permethrin and pyrethrin being some of the active ingredients.

Dusting or spraying at an early stage will help prevent adults from entering tender plant parts and laying eggs. Bacillus thuringiensis (Bt) is listed as a biological option and will provide control if applied before the small caterpillars enter ears.

For a complete listing of treatment options access the Aggie Horticulture web site at: http://aggie-horticulture. tamu.edu When using any insecticide always read and follow the label on the product.

Unfortunately, regardless of the control program used, chances remain that some ears will be damaged. However, most damage will be confined to the ear tips.

These ears are still edible. The damaged portions can be removed by clipping off the tips as the corn is shucked and prepared for cooking.