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Not all Bugs are Bad
By Lucy Owsley

Any gardener can tell you horror stories of the devastation left by bugs. From the smallest back yard garden to the largest agricultural fields insects have been responsible for their ruin. The pesticide industry relies on our fear and loathing of all insects to make huge profits. We buy or make sprays and dusts. We plot out our strategy against these seemingly indestructible and possibly immortal beings all out to eat our flowers and vegetables. We go out armed with potions and powders, sprays and solutions all aimed at the multitudes of ravenous bugs eating our gardens and fields.

But are all bugs all bad? Actually more than 90% of the insects you find in your back yard are either beneficial or neutral. Another thing to know is a plant can lose up to 855 of their leaves, flowers and fruits and be just fine. This means when you see an outbreak of say, aphids, before freaking out and spraying them to kingdom come first look to see if a) is there a lot of damage? Are the leaves very curled, major branches missing? b) are there aphid eating (beneficial) insects having lunch on the aphids? If you see ladybugs, green lacewings than put the sprays away. Even the organically correct soap sprays. Do nothing and let the beneficial help you out.

When you spray poisons you kill ALL the insects not just the ones doing damage and generally in a well balanced environment the beneficial will equal the bad guys so that there is rarely much insect damage in the garden. Oh sure there will be holes in leaves and even the occasional tomato or bloom lost to pest insects but the bulk of the harvest will still go to the humans not the insects.

By now you are probably wondering just which bugs are the good guys, what do they eat and how can you attract them to your garden? First off to attract beneficial insects they need a water source and a place to hangout and no insecticides. The water source doesn't have to be anything fancy, a dripping tap will do. Living conditions can be an unmown part of your yard full of nectar and pollen producing plants such as Queen Anne's Lace, cilantro (coriander) or a butterfly type garden.

The Insects:

Assassin Bug-these eat many different insects including catapillers and flies

Big eyed Bugs-eat aphids, small caterpillars, leafhoppers, spider mites and tarnished plant bugs

Brachinoid wasps-tiny stingless wasps that parasitize their prey. Look for mummified aphids or white cocoons on caterpillers. They prey on aphids, army worms, beetle larva, flies, gypsy moths etc..

Damsel Bugs- These hang out in alfalfa fields and are an important orchard predator. they eat aphids, small caterpillars, plant bugs, thrips and treehoppers

Ground Beetles-These nocturnal predators go after soil dwelling pests such as cabbage root maggots, cutworms, slugs, snails. Some species prey on above ground pests such as the Colorado potato beetle larvae, gypsy moths and tent caterpillers.

Honey Bee-These and other wild bees are essential for pollinating most flowers in the garden. Bees are very sensitive to pesticides

Hover Flies These look a lot like bees but smaller and with big green eyes. And they hover. These guys love about any aphid.

Ichneumon Wasps-another usually a tiny stingless wasp. The larger versions have very long ovipositors that look like stingers but are completely harmless. they prey on catapillers, sawfly and beetle larva, other insects

Green Lacewings-The larva are known as aphid lions and have a voracious appetite for all soft bodied insects, including aphids as well as small catapillers, mites, moth eggs and some scales

Lady Bugs-The best known of the benificials. Adults eat but their larva are the big eaters of aphids, mealy bugs, soft scales and spider mites. lady bugs can come in many colors including ash gray, black, yellow or orange with black spots or blotches

Minute Pirate Bug-these eat small catapiller, leafhoppers nymphs, spider mites, thrips, eggs of many insects

Praying Mantis-One of the larger and more dramatic of the garden predators. These eat flies, catapillers, beetles, wasps, spiders etc

Rove beetles-many eat aphids, fly eggs, nematodes, springtails; some parasitize cabbage root maggots and other fly larvae. Looks like an earwig but has no pincers and are smaller.

Soldier beetle-Prey on aphids, beetle larvae, especially cucumber beetles, caterpillars and grasshopper eggs. Unlike most beetles these have leathery instead of hard wing covers

Spined Soldier bug-These eat fall army worms, hairless caterpillars including tent caterpillars;sawfly larvae, beetle larva, especially Colorado potato beetle and Mexican bean beetle. These looks like a stinkbug but the spined soldier bug have sharp points on the "shoulders" of the thorax.

Spiders-Spiders eat a lot of flying insects including white cabbage moths, grasshopper, flies and many beetles.

Tachnid flies-These prey on numerous species of caterpillars, Japanese beetles, may beetles, sawflies and squash bugs. This is the largest and most beneficial groups of flies. they look a lot like a housefly. don't kill caterpillars with white egg stuck to their backs as the eggs will become the next generation of tachinid flies.

This list is the major players in the insect predator world. There are others as well. I would advise any serious gardener especially organic gardeners to obtain a good field guide to insects in your area. Both Audubon and Petersen's publish excellent insect field guides. The guides will have pictures of beneficial insects as well as most of the bad guys.

With this knowledge you will start to notice a whole new world and will start watching all the drama that has been happening all this time right under your nose. You will also find that gardening will cost less as you learn to less pesticides and to be very discriminating when you do resort to the sprays and dusts. Soon you will cease to look at insects as bringers of devastation but rather as denizens of a tiny world most people never take the time to notice.

Copyright Lucy Owsley, February 14, 2001