JULY
1988

 

 

 

By
Tom Turpin
 
Professor of
Entomology
Purdue University

 

 

 

 

 

7-14-88

Chewing Machines

Grasshoppers are among the most recognizable insects on earth. Perhaps it's because of their chewing mouthparts. Grasshoppers have the type that show up in horror movies. Or it might be because of their hind legs. Those legs are used for jumping, and hence, the name—hopper.

But the truth is that grasshoppers are well known for their appetites. The eating habits of grasshoppers make them one of the world's worst insect pests.

Grasshoppers have been known as a pest for thousands of years. The bible contains several references to grasshoppers—sometimes called locusts—as pests. For example, in Joel 2:3 we read,  “… the land is as the Garden of Eden before them and behind them is a desolate wilderness; yea, and nothing shall escape them. “  The eighth of the plagues visited upon Egypt preceding the Exodus was a great mass of locusts, which, according to biblical account, ate all the vegetation on the land so that nothing was left.

Grasshoppers primarily feed on green foliage, but when food is scarce they will feed on almost anything. Tales have been told of grasshoppers eating straw hats left in the field. In the Dust bowl days, wooden pitchfork handles were said to have been nearly consumed by hungry grasshoppers.

Grasshopper problems are the most pronounced when the weather is dry. Biological control of this insect is reduced under dry conditions. For instance, under wet spring conditions, the egg masses, which are the overwintering state of grasshoppers, are attacked by a fungus disease. This disease eliminates many hoppers before they hatch.

In the arid regions of Africa, the migratory locust is a continual problem. During the drought periods of the 1930s and the 1950s, grasshopper damage to the U.S. crops was high. And in unusually dry years, such as 1988, grasshopper problems normally increase.

Many approaches to grasshopper control have been used of the years. During the 1930s in the Midwest, hopperdozers were used. Hopperdozers were grasshopper—catching machines placed on the front end of a truck or tractor. As many as eight bushels of hoppers were collected per acre using one of these devices. Such a grasshopper population has been estimated to consume a ton of alfalfa hay per day in a 40-acre field.

More recently, people in Africa have tried to keep the insects from damaging crops by driving them away. Today, large swarms of grasshoppers are sometimes sprayed during their flights with an insecticide carried by aircraft.

Another way to kill grasshoppers is to include a poison in a bait. An enterprising entomologist during the 1930s even mixed poison with horse manure for use in controlling grasshoppers.  Reports are that the bait worked quite well.

As a last resort, some peoples of the world have taken to eating grasshoppers. However, such an approach has not been widely accepted in the United States.  It seems that eating up an insect problem—especially grasshoppers—just doesn't appeal to our tastes.

 

Writer: Tom Turpin
Editor: Steve Cain