High Elevation Gardening Web Log "Blog"

Akin to a blitzkrieg, a lightning war, invading grasshoppers can only be fought with counter-terrorist tactics. In war the difference between strategy and tactics is the difference between a plan of action and the means by which that plan is executed. An inexhaustible reservoir of grasshoppers makes annihilation impossible. A pre-emptive strike won’t work because they’re everywhere.

The strategy is to cripple and reduce them to ineffectiveness with a series of tactics both repeated and diverse and a comprehensive defense in which the gardener is prepared before the attacks begin.

The first line of defense is a lethal series of traps. A fixed line of defense, such as the French Maginot Line in World War II, won’t work because the grasshoppers will pull an end-run, just as the Germans did in 1941. In a mobile defense, the traps are placed where grasshoppers are likely to attack, such as those bare undisturbed spots where the pods of eggs are buried, especially in the garden’s perimeter.

An effective trap is both attractive and lethal. Grasshoppers find wheat bran toothsome. Mixed with either NoLo or Sevin, it is both attractive and lethal, a real winner.

NoLo, short for Nosema locustae, isn’t a poison, but a disease which favors grasshoppers and isn’t a threat to anyone else, such as children, pets, and birds. Sevin is the commercial name for the pesticide carbaryl. While there have been no reports of human deaths from carbaryl, it’s still a poison and must be used carefully as with any deadly weapon. As a recipient of friendly fire years ago, I urge caution since carbaryl is lethal to a gardener’s allies, honey bees, parasitic wasps, birds, and lady bugs.

If carbaryl is sprayed as a shotgun, collateral damage will result so it’s best used instead with wheat bran. Happily, carbaryl disintegrates rapidly, loosing its lethal potency, but this means repeated use.

The traps are best laid in barren spots and amongst tall grasses where our allies won’t suffer collateral damage and far away from plants attractive to honey bees and from bird feeders. An in-depth defense for those grasshoppers who make it through the perimeter defense are tin cans with both ends cut out, partially sunk in the soil, placed in the middle of the garden with the bait placed inside the can.

Older and more developed grasshoppers will take longer to die than the nymphs. They will become lethargic, jumping about as though drunk, easy target for their cannibalistic kindred.

Since grasshoppers never stop, NoLo and Sevin should be applied regularly from early spring to late autumn. Happily, NoLo has a residual effect and may carryover from year to year, gradually building up a lethal arsenal, even afflicting the egg-laden pods.

The next line of defense is airborne, such as squadrons of birds and praying mantis. Several bird feeders throughout the yard help to develop a resident corps of birds ready to attack from the air. Pods of praying mantis eggs purchased from commercial nurseries can be hung in trees. When hatched they favor grasshoppers. Turkeys and other domesticated fowl, if allowed by local government, devour grasshoppers with gusto.

When spotted, remember the words of Admiral William F. “Bull” Halsey, Jr., of World War II fame. “Strike, Repeat Strike.”

Dana Prom Smith is a Master Gardener volunteer and coordinating editor of the Master Gardener Column for Coconino County Cooperative Extension. He can be contacted at stpauls@npgcable.com. For more information about the Master Gardener Program, call Hattie Braun, the Master Gardener Program Coordinator, at 774-1868 ext.17 or visit our Web Site: highelevationgardening.arizona.edu.