Chewing Insects - Chewing Insects

General Description

The two major groups of insects that cause damage to plants via their chewing mouthparts include the caterpillars and beetles. Other chewing insects that are sometimes damaging to plants include grasshoppers, katydids and their relatives.
Caterpillars are the immature or larval stage of moths and butterflies. Their bodies are usually cylindrical in shape and either slender or robust. However, some are oval and others are flattened. They may be striped, marked with various color patterns or solid in color. They also may be naked, extremely hairy, or possess tufts of hair. Most mature larvae are 3/4 - 1 1/2 inches long, but some are much smaller and some may be more than 4 inches long. Caterpillars have three pairs of jointed, true legs on the thorax and usually four pairs of soft, fleshy projections (prolegs) on the abdomen, with a fifth pair at the extreme rear of the abdomen. The prolegs have tiny hooked spines (crochets) to aid in holding on to leaves and other plant parts.

Many species of beetles frequently cause injury to woody ornamentals. Both the adult stage and the larval stages are injurious and both have chewing mouthparts. Some beetles, such as lady beetles, are extremely beneficial in both the larval and adult form. Adult beetles vary in size tremendously. Some are less than 1/8 inch long while others are more than 2 inches in length. They may be any color or combination of colors. However, the most common colors are black or brown. The larvae of beetles vary greatly in feeding habits, body shape, size and color. Some species feed on leaves while other species feed on roots. Some are elongate with relatively long legs and may be brightly colored while others, usually grubs, are robust, C-shaped and white with a brown head. Mature beetle larvae vary from 1/8 inch to over 2 inches in length.

Grasshoppers are 3/4 to almost 3 inches in length, gray or brownish and some have brightly colored hind wings. The lubber grasshopper is the largest grasshopper in Florida. Adults often exceed 2 1/2 inches. They have very short wings, are clumsy and incapable of flight. There are two color forms of the adult lubber grasshopper. Some are yellow with red, brown and black markings and others are almost black. The nymphs are black with red markings.

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