During the colder months of fall and winter, garden pests go underground or die off. Unfortunately, this is not true in the southern parts of the United States. Louisiana’s warm, mild autumns and winters allow for these insects to continue harassing gardeners all throughout the year without the normal cold weather reprieve. Crops like corn, cabbage, lettuce, spinach, broccoli, peas and carrots are in jeopardy of being ruined by these annoying bugs.
There are many species of caterpillars in Louisiana. Caterpillars have three pairs of jointed legs upon each side of their bodies. They vary in colors and patterns as well as size. Caterpillars are usually classified as a beneficial insect in gardens, but with Louisiana’s warmer climate, these insects become a problem for fall crops. These insects feed heavily in the autumn before going into their cocoons to emerge as butterflies for spring. Normally, caterpillar species only eat one type of plant in the garden. Caterpillars consume spinach, broccoli, Brussels sprouts, eggplant, lettuce, mustard and cabbage.
Pea Aphid (Acyrthosiphon pisum)
Pea aphid love the fall because of the lower light levels and cooler temperatures. They are 1/16 to ¼ of an inch in size and have oval-shaped bodies that vary in color from black to white or pink and green. These insects are very destructive to many plants by draining the liquid from the plants' leaves and stems. Aphids carry diseases to plants and can soon kill a whole crop with an infestation. Avoid high nitrogen fertilizers and check plants often; if aphids are attacking a plant, use water to remove them. They like to feed upon peas.
Greenhouse Whiteflies (Trialeurodes vaporariorum)
Greenhouse whiteflies are cold-weather insects that are usually found indoors or in greenhouses; however, they can become outside garden pests as well. They resemble tiny white moths with two wings and are 1.5mm long. Whiteflies produce a sticky secretion that coats the leaves of plants. These bugs feed off the undersides of leaves, ingesting the plant’s liquid nutrients eventually leaving the plant in a weakened state. In order to control their population, use a shop vacuum to suck them off the leaves of garden plants. Whiteflies like to eat cabbage, cauliflower, tomato, eggplant and onions.
Brown Stink Bug (Euschistus Servus Say)
The brown stink bug is well known throughout the southern part of the United States. It has a long shield formation for a body with grayish-yellow spots upon its back and sucking mouth parts. The length of the body is 10 to 15mm for the adult insects. These bugs damage plants by puncturing them with their sharp needle mouth pieces. They destroy leaves, stems and seed pods by injecting toxins into the plants while they feed. Brown stink bugs are known to eat corn, okra, snap beans and peas. Stink bugs are hard to manage, as they are tolerant to many insecticides.