Manage 3 pests with early intervention

Grasshoppers and raspberry crown borers are summer pests that can be devastating to a home garden and yellow jackets can be at the very least, nuisances. Agricultural crops and landscape material may be seriously damaged by bad infestations of grasshoppers. As a home gardener, you have time to manage all of these pests.

In early June, the majority of grasshopper species are in the beginning nymph stages. If you are going to use a chemical control it should be done at this stage. Carbaryl or dimilin can be used to control nymphs, but is not effective at the adult stage during early summer and fall. Always use care when spraying insecticide. Often creating a border of insecticide will be enough to keep them out of larger areas. If an organic method is preferred you may want to look at keeping chickens on small acreage or looking for recipes for homemade molasses baits to keep them off of landscape plants. Grasshoppers also prefer dry areas. Home owners can discourage grasshoppers through the use of sprinklers and increased water.

Raspberries can be attacked by the raspberry cane borer leaving dead canes in its wake. The adult form is a clear winged moth. With its yellow-striped, black body it resembles a yellow jacket or wasp. After the moth's eggs hatch, the white larvae with brown head make the journey down the cane to below soil level. They begin boring tunnels in the canes and by their second summer of life, the crowns can be completely hollowed out and dead. You will know you have an infestation if the canes break off easily at soil level if pulled gently from the ground. If you discover the infestation in the fall, prune out and destroy the infested canes. Insecticides applied to the crown in the spring just before buds emerge will lower the number of larvae. Repeat the insecticide application a year later to arrest the two year life cycle of the borer. The least toxic chemical method is pyrethrin and rotenone insecticides. The only organic method is the removal and destruction of all infected canes.

Yellow jackets are considered beneficial in that they eat other insects pests. For most people yellow jackets can ruin any event where food and drink are available. Areas on your property used for entertaining, outbuildings that are used frequently, and popular play areas for children will be places to focus your attention. Trapping the queen in early spring will prevent a colony from forming in your area. The yellow plastic traps available in most home and garden stores are ideal for trapping the queen, just as they are for control of an established nest of worker wasps.

Early detection and treatment in early June can prevent future problems with insect pests during the summer months.

For more information contact the Montana State Extension Office at 758-5553.

Anderson is a Flathead County Master Gardener.