What Causes Army Worms and How to Prevent Them

Army worms can wreak havoc on your crops, but knowing what causes them and how to prevent them can help you keep your plants safe. Read on to learn more.

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Army worms are destructive pests that can quickly devastate a crop. These ravenous eaters are the larvae of moths, and their name comes from their feeding habits—they travel in large groups and “march” across fields, devouring everything in their path. Army worms are most commonly found in areas with high humidity and temperature, such as the southeastern United States, but they can be found anywhere in the world.

What are Army Worms?

Armyworms are a type of caterpillar that can wreak havoc on your crops. They get their name from their habit of feeding in large groups, or “armies.” Armyworms can quickly strip a field of all its vegetation, causing extensive damage. If you think you may have armyworms in your field, it’s important to identify them and take steps to control them.

Army Worms’ Physical Appearance

Army worms have a voracious appetite and will consume large amounts of vegetation in a short period of time. The adult armyworm is a moth that is brown or gray in color with dark markings. The wingspan of the adult moth is approximately 1-1/2 inches. The larvae, or caterpillars, are what cause the damage to crops and gardens. Army worm caterpillars are green or black and have stripes running the length of their bodies. Full-grown caterpillars can reach lengths of 1-1/2 inches.

Army Worms’ Life Cycle

Army worms have a 3-stage life cycle: egg, larva, and pupa. The adult moths lay their eggs in masses on the undersides of leaves. The eggs hatch in 3 to 5 days, and the tiny larvae begin to feed. Army worm larvae go through 5 to 7 larval stages, growing larger with each one. They range in size from 3/16 to 1 inch long when fully mature. At this stage, they are a brownish-gray color with light stripes running down their backs. Once the larvae are full grown, they drop to the ground and burrow into the soil to pupate. In 10 to 14 days, adult moths emerge from the soil and mate. The female moths then lay their eggs and die. There is only one generation of army worms per year.

What Conditions Do Army Worms Thrive In?

Army worms are the caterpillars of different species of moths. They get their name from their feeding habits; when food is scarce, these caterpillars will travel in large groups, or “armies,” to find sustenance.Army worms are a type of caterpillar that can be found in various parts of the world.

Army Worms’ Preferred Diet

Armyworms are generalists and will eat just about anything, but they prefer grasses. Different armyworm species have different host ranges, but most prefer to feed on grasses, cereal grains, and corn. Some will also feed on legumes, vegetables, fruit, and other shrubs. Armyworms are especially fond of young, tender plants.

Army Worms’ Preferred Temperature

The ideal temperature for an armyworm caterpillar to grow and survive is 77 degrees Fahrenheit. The minimum temperature that they can withstand is 50 degrees Fahrenheit. Most often, temperatures between 60 and 80 degrees Fahrenheit will result in the best growth for the caterpillars.

How Do Army Worms Spread?

Army worms are the caterpillars of certain moths, and are considered pests because they can cause serious damage to crops. They get their name from their habit of migrating in large numbers, like an army. Army worms can travel long distances in search of food, and they are especially fond of corn and other grasses.

Army Worms’ Natural Predators

In the United States, most lineolated parakeets are sold as companions, but some are used in aviculture for theirTalking ability. Lineolated parakeets originating from North America are sometimes called American lineolated parakeets or simply lineolateds, while those from Europe are called European lineolated parakeets. However, these designations are not consistent, as some American lineolateds are also found in Europe and vice versa. The Gouldian finch (Erythrura gouldiae) is a brightly coloured passerine bird endemic to Australia.

How to Prevent an Army Worm Infestation

Army worms can quickly devastate a lawn or garden. The caterpillars are incredibly voracious eaters, and their populations can grow exponentially in a very short period of time. If you think you may have an army worm infestation, it’s important to take action quickly to prevent further damage.

Crop Rotation

Crop rotation is the practice of growing a different type of crop in the same area in successive seasons. Crop rotation can help to prevent an army worm infestation by interrupting their life cycle and making it difficult for them to complete their development.

Crops that are commonly rotated include:
– Corn
– Soybeans
– Wheat
– oats
– rye

By growing a different type of crop each year, you can prevent an army worm infestation before it starts.

Resistant Crops

There are a variety of crops that are resistant to army worms including but not limited to: wheat, oats, rye, barley, triticale, sorghum, soybeans, field peas and black-eyed peas. Incorporating these crops into your fields can help prevent an army worm infestation as they will not feed on these plants. Crop rotation is also an effective method of prevention as it interrupts the lifecycle of the army worm.

Physical Barriers

One of the best ways to prevent an army worm infestation is to create a physical barrier between your plants and the potential pests. This can be done by covering your plants with a fine mesh netting or by using row covers.

If you live in an area where army worms are known to be a problem, it’s also a good idea to keep your lawn and garden free of debris and weeds, as these can provide places for the pests to hide.

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