MARCH
2002

 

By
Tom Turpin
 
Professor of
Entomology
Purdue University

 

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Check out these books by Tom Turpin:

Flies in the face of fashion

What's Buggin You Now?

 

 

 

3-14-02

Download the audio of On Six Legs: MP3, WMV.

Insect Good Guys Don't Wear White Hats


The month of March brings with it an annual major human disease epidemic that sweeps across Midwestern states. No, it is not the flu, measles or mumps. This disease is far more widespread than those human maladies. It is called the garden itch!

Yes, every spring folks young and old succumb to the disease. No one is sure what causes garden itch. It might be the garden catalogs that sprout in large numbers in our mailboxes. It might be the overnight appearance of garden products outside of every store in town. Or it might be the song of the cardinal from the treetops or the flocks of robins hopping around on our lawns.

Not everyone succumbs to the disease, however. Some folks apparently are immune. Their immunity might be inborn; more likely, it has developed over the years following exposure to the disease. But most of us remain susceptible to garden itch and exhibit symptoms of the disease. We buy seeds, spade the garden plot, plant the seeds and prepare to do battle with the insects that show up!

Yes, just as surely as gardeners plant each spring with visions of ripe tomatoes and new potatoes dancing in their heads, insects will show up. Most gardeners take great delight in sharing the fruits of their labors with neighbors, which is why most of us don't have to plant zucchini! But to share with insects is an entirely different matter.

So, when the insects show up, most folks infected with the garden itch display another symptom of the disease -- a maniacal attempt to kill the pests. To many gardeners, the only good bug is a dead bug!

One approach to getting rid of unwanted insects is to allow nature to lend a hand. Some insects have been called friendly carnivores because they eat those insects that feed on our garden plants. Scientifically, the process is known as biological control.

But who are the good guys? Unlike in the old western movies, the good guys in the garden do not wear white hats. To most people, the good guys and bad guys look pretty much the same. You know: three body sections, antennae and six legs.

The most common of the garden good guys are the lady beetles. Sometimes called ladybugs, these insects are the most easily recognized of the garden-beneficial insects. There are dozens of species, but most are a round or oval shape, brightly colored and spotted. The females lay large masses of yellow-colored eggs on leaf surfaces. The immatures look much different than the adults. They are wingless, elongated and usually dark-colored with spots of red or orange.

Like lady beetles, another of the garden good guys commonly feeds on aphids. This is the lacewing. The most common are green in color and are delicate, soft-bodied insects with large, clear wings with many veins. The wings are held over the body when the insect is at rest. The immature of the lacewing looks, in shape, much like the immature of the lady beetle.

Another beneficial insect is a fly called the sryphid. This fly sometimes is called a flower fly or hover fly. The latter name is based on its habit of hovering in one place for a long period of time. The hover flies are also incorrectly called sweat bees, since many species are colored like bees. Some of them will land on humans and collect sweat with their mouthparts. They won't sting or bite, even though they look like bees.

Other good guys include several of the true bugs. Most stink bugs are predators on other insects, as are the assassin bugs, minute pirate bugs and damsel bugs. You can tell bugs because their wings are half membrane and half leathery! But watch out! Some bugs, like the squash bug, are major garden pests.

So, if you are infected with garden itch this year, it makes sense to buy a book with pictures of the garden good guys. After all, you probably won't be able to identify the players without a program!

 

 

Writer: Tom Turpin
Editor: Olivia Maddox