One of the e-mails I received this week was from the owner of a local equestrian center. The question was why they seem to have armyworms in their pastures about this time each year. The truth is that armyworms have been so consistent about showing up the last few years, it seems that cattle and horse ranchers can almost plan on them appearing in late summer. From the looks of things, we need to be on guard again this year.

The second part of her question was if there were something she could do to prevent the armyworms’ occurrence. The best answer to that question is no. It is really better to control armyworms only after they appear and after they reach the damaging levels we refer to as economic thresholds.

Armyworms are not only pests to forage and hay producers, though. Late summer and early fall are the peak season for fall armyworm invasions of well-managed turf, too, especially Bermuda grass lawns, athletic fields, and golf courses that have been fertilized and watered.

With the advent of football season upon us, it would really be an unpleasant situation to have the Friday-night playing surface disfigured by an invasion of armyworms.

Folks who take a lot of pride in the appearance of their home lawns wouldn’t appreciate that kind of damage either. Believe me, the treatment threshold for golf courses, football fields and many lawns can be quite low, meaning very little damage will be tolerated.

The armyworm adults or moths migrate in large numbers and lay as many as a thousand eggs each. During these hot days of summer the eggs hatch in only a few days with the tiny caterpillars feeding almost continuously.

When small they may go unnoticed while consuming only a small amount of leaf tissue daily but nearing their last few days as larvae they can literally devour an entire lawn almost overnight. Therefore, it is important that a careful scouting regime be established to detect their presence and control them while they are small.

At least once a week during the remaining growing season randomly check several locations in the lawn by brushing the grass back and forth with your hand, parting the blades down to the soil line and looking for coiled light-tan or green to nearly black caterpillars.

If you care to pick one of them up and look at it straight on you may notice a small inverted “Y” marking on its forehead.

Control is not too difficult if the lawn is treated with an appropriate insecticide when the caterpillars are small.

Liquid sprays or granules containing active ingredients of carbaryl, cyfluthrin, permethrin, lambda-cyhalothrin or trichorfon are recommended.

Reminder: Mississippi State University will host a Muscadine Field Day at the McNeil Experiment Station Vineyard on Highway 11 at McNeil, Miss., Thursday beginning at 9 a.m. Almost every named muscadine variety in existence is included in this vineyard.

Contact the Extension office for program topics and directions to the McNeil station.

John C. Coccaro is county Extension director. Write to him at 1100-C Grove St., Vicksburg, MS 39180 or call 601-636-5442. E-mail him at jcoccaro@ext.msstate.edu