For years entomologists have warned that fall armyworm outbreaks are the highest when rainfall follows an extended period of drought. That fact has certainly held true this year.

Populations are extremely high and long time Kleberg residents state that worm activity has not been this great since the early 1960s.

A quick check of coastal bermudagrass in the Ricardo area earlier this week found worms of varying sizes.

Numbers were well over the three or four per square foot threshold for damage.

However, many worms were found that had succumbed to parasitic wasp, disease and fungi.

Hopefully these natural enemies are starting to put a dent in the population and will limit another damaging outbreak.

As these gluttonous pest have marched across the area, devouring hay patches and pastures, many people have contacted the Extension Office with questions regarding the armyworm’s life cycle.

Female armyworm moths are very prolific laying 50 to 100 eggs on individual blades of grass.

Even more disturbing is the fact that some entomologist report that the moth has the ability to deposit up to 2000 eggs.

Two to three days following a lay, the eggs hatch and the worm’s march across pastures and hay meadows begins.

Since the destructive pest is very small at hatch, infestations often go unnoticed. However, as the larvae grow their food intake increases.

About 2 weeks after hatch the larvae have increased greatly in size and their appetite is enormous.

Damage is easily seen when worms reach this growth stage and are 1 to 1-1/4 inches in length.

As the larval stage nears its end, feeding and damage becomes colossal. 80% - 85% of the worm’s total food intake occurs in the four-day period before the pest enters the pupal stage.

Once the armyworm completes feeding, it tunnels into the soil about an inch and pupates.

In 7 to 14 days, the armyworm moth emerges and the cycle repeats. Emerged adult moths often move long distances to find habitats favorable for laying eggs. Development from egg to adult requires three to four weeks and is is influence by weather. As would be expected, cool conditions slows development.

The fall armyworm moth has a wingspan of about 1-½ inches. The front pair of wings is dark gray with an irregular pattern of light and dark areas.

Outbreaks of the pest can’t be assessed by moth numbers due to the fact that the moths are most active at night and therefore seldom seen.

Insecticide treatment is effective in controlling the pest if the worm is caught early in its life cycle.

The key to managing fall armyworms is to detect infestations before they have caused economic damage.

Close inspection for early detection is a must when battling the fall armyworm.

When caught in a timely fashion, there are a number of products labeled for use on the fall armyworm.

Be aware that some of the products have a grazing, haying or grazing and haying restriction.

Please read and follow label directions when utilizing any insecticide