Rivercities Garden Club

Meeting 06/04/00

Program   Garden Insects both good and Bad - Dr. Mike Hall

Dr Hall presented an enthusiastically received question and answer session about insects both good and bad. Dr. Hall is an entomologist who spends most of his time running clinics to control pecan pests, and most recently is building greenhouses so that the insect problems of commercial greenhouses can be evaluated, He relates that he is interested in insects in general; and noted that he enjoyed collecting bugs as a child.

Dr. Hall estimates that there may be over 30 million types of insects. Generally insects are not harmful. Their beneficial roles include pollination, food, for woodworkers - shellac. Decomposition. of organic matter is very important;t and he believes that were it not for insects we would not be here.

When finding a new bug, consider the esthetics of the creature. Look at the wings; look at the wing patterns. Though some insects have a minimal of coloration, others can be brilliant whit iridescent colors changing with the direction of sunlight.

Characterization of bugs can be a simple process for a gardener. You need to know if the bug is a good or a bad bug. Some are good, some clearly bad, others may be either good or bad depending upon their development cycle.

Beneficial bugs:

 Mosquito hawks - adult doesn't feed. they are a type of fly, and they don't eat mosquitos

Dragon flies are most beneficial. They will eat over 200 mosquitos a day. nymphs will eat mosquito larvae.

Insects bad & good moths and butterflies feed on plants when immature. moths rest wings back, butterflies wings up. moths feed on most everything. Tomato horn worms make pretty moths.

Assassin bugs - eat other bugs. They can be recognized by very heavy mandibles.

Rolly polly bugs (or pill bugs) eat decaying matter. don't hurt anything and help the development of dead plant matter into mulch.

Wasps are beneficial - it is predator and parasitic on other types of insects. Females sting; males don't. Great variation in size of wasps. You should leave them alone if they don't bother you.

Spiders also beneficial - leave them alone.

Scarab Beatles are helpful by feeding on dung and are beneficial

Lady bugs are good as predators

Love bugs which are particularly prominent in south Louisiana are harmless except that they nightmare on car paint

Yellow jackets are beneficial by laying their eggs in other insects which have a tendency to eat plants.

Bad Bugs: These insects have a tendency to damage or destroy plants or crops. Plant feeders are generally bad.

Carpenter bees - wait till they go into their next then caulk up their nest. or seven or malathion

Tent caterpillars are more of an esthetic problem here. They won't kill the tree.

Stink bugs - can be good or bad. The dark ones are Predictors feed on other pests. the green stink bug is a pest.

The cicadas causes damage to tree similar to fire blight. The tips of trees die back. If you look you will find slits in the bark.

June bug - they are bad eat roots

Fire ants don't kill plants use orthine, durispan, diazanon, or ortho bait

Indian cereal moths can eat everything and anything. Frequently get into the house are about 1/2 inch long and have brown wings.

Insect Control:

Controlling insects may not need insecticides. Consider picking them off if there are just a few or use other mechanical destruction. If you don't see anything don't worry about it. If the plant or garden is grossly infected with insects then you may need insecticides.

No insects protected by law in Louisiana

Dishwater can be an effective treatment of aphid and white fly. Such soaps as Sapher's insecticide soap are available.

Scales - Use summer oil . As an insecticide oils tend to be somewhat more safe to use. It is necessary to completely cover the insects and has a relatively short residual.

Prometherine has a very short residual as an insecide and seven has a residual of about 1 week. Getting rid of old insecticide is not a problem. Just use it. Even though old, it may well be effective. Tripple rinse the container and then you can dispose of the container. But consider buying small amounts the next time you purchase the chemical. Read environmental impact on the insecticide that you buy so that you have some idea of the impact of the chemical on other organizisms in your garden such as worms, beneficial insects, and birds.

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