The Mahnomen Pioneer

AGRICULTURAL NEWS LETTER

Reduce Tree Losses By Insect Control

Proper care of trees in shelterbelts, ornamental plantings, or woodlots involves guarding against ever present insect depredations as well as keeping protection from mechanical injury, says Parker O. Anderson, extension forester, University Farm, St. Paul. Recent examinations in many groves indicate some loss of growth due to leaf-eating insects, Mr. Anderson says. These occur in hundreds of varieties, colors, and shapes but all may be controlled by covering the surface of the leaves with arsenical poisons such as arsenate of lead or Paris green which will be taken into the stomachs of the insects when the leaves are eaten. Other insects that are causing grave concern to tree growers this year are plant lice, which suck the juices from the leaves or stems, thereby gradually weakening the trees. The action of the aphids causes many malformations of leaf and stem such as galls and rolled leaves. Because of the manner in which plant lice feed, stomach poisons sprayed on the leaf surfaces will not control them. An insecticide must be used which will kill by contact, either by closing up the breathing pores or by corroding the body. Spraying with "Black Leaf 40" or nicotine sulphate will be found highly satisfactory. These materials can be purchased at most drug stores and directions for mixing them with water will be found on the packages.