grasshopper

=American Grasshopper (**Phylum**, Arthropoda; **Class**, Insecta; **Order**, Orthopter)=

By Nathan Gartin


= = =Introduction=

Grasshoppers are a very commonly found insect not merely just in the Ames High prairie, but also throughout the entire Midwest. Grasshoppers have two wings: forewings narrow and relatively hard, and hind wings large and membranous. The antennae are not particularly long, 20-24 segments. They have conspicious eyes and unjointed cerci (a pair of appendages at the end of the abdomen.)

Distribution
Of North America, the American Grasshopper may be found in the following states: Kentucky, Tennessee, Mississippi, Alabama, Georgia, North and South Carolina, and Virginia. It also may be found in the Bahamas and Mexico.

Life Cycle
The American grasshopper has two generations a year and overwinters in the adult stage, unlike most grasshoppers whose eggs survive the winter. Thus, American grasshoppers are present throughout the year. The two hatching periods are from April to May, and again from August to September.

Grasshoppers produce two generations of young a year; once from April to May, and later from August to September. Adults can survive winter, while the eggs cannot. However the eggs of other species can survive the winter.

**Egg:** The female American grasshopper deposits her eggs in the soil about 2 to 3 cm below the surface by pushing her ovipositor down into the substrate. Female grasshoppers lay their eggs 2 to 3 cm below the ground with their ovipositors. Grasshoppers lay their eggs in places with lots of debre and objects to hide under. They lay their eggs in clusters that carry 60 to 80 eggs. The eggs are held together by a milky, polymer-like substance that is secreted by the female. Females will lay no more than three egg pods. Eggs are 7 to 8 mm in length and are light orange in color.

**Nymphs;** grasshoppers hatch in about 3 to 4 weeks. Once born, grasshoppers start as nymphs. The nymphs hatch from the eggs in three to four weeks and must work their way to the surface. The nymphs have five to six stages to go through before they reach adulthood. These stages are called instars. Six instars are normal, but if there are not as many nymphs there probably will only be five instars completed. If there are alot of nymphs the latter instars will be more yellow, orange and black, than green. At lower densities, nymphs may be completely green in color. When it comes to defining what instar the nymph is at, it is best to pay close attention to the wings. The wings start off absent, then go to a wing pad, to a more developed wing pad, and then finally to the full grown wings. However other factors apply as well. - The first instars are pale green with a black mid-dorsal stripe running the length of the body. It is 6 to 7 mm in length and has 13 antennal segments. - Wing pads and 4 more antennal segments come about in the second instar. - In the 3rd instars, the length changes from 16 to 18 mm, antennal segments go from 21 to 22, and the wing pads take on a triangular shape. - In the fourth instar the antenna goes from 22 to 24 segments. Wing venation becomes present. - In the fifth instar the direction of the wing pads changes from ventral(Pointing toward the ground) to posterior (Pointing horizontally). Also, it will have a length of 27 to 30 mm. Antennal segments will be 24 to 25 in number. The sixth will be 35 to 45 mm in length and have 25 to 26 segments in its antenna.

**Adult:** Adults can be described as carrying fullydeveloped wings with unique brown spots. Their color changes from the green of the nymphs to reddish brown.The male's length is 39 to 42 mm. The female is only 48 to 55 mm in length. As the grasshopper reaches the reproductive stage, it changes to a yellow/brown color.

Dangers to Crops
The American grasshopper is known to be capable of wreaking destruction on many different kinds of crops, including: corn, oats, rye, peanuts, sugarcane, tobacco, cotton, vegetables, and citrus. Grasshoppers tend to gnaw on the leaves of plants. Sometimes they can even eat young vegetables right off the ground. Most damage done by grasshoppers is isolated to the the third, fourth, and fifth instars. These younger grasshoppers require much more food than the older. In addition to crops important to human society, grasshoppers also will eat bahiagrass, bermudagrass, dogwood, hickory, crabgrass, woodsgrass and nutgrass.

Sources

1. http://insected.arizona.edu/ghopperinfo.htm 2. http://creatures.ifas.ufl.edu/field/amhopper.htm#dist