How to Kill Armyworms on Apple Trees
- 1). Limit overgrowth in apple orchards. Armyworms prefer the dark and are usually only active at night; excessive overgrowth provides shade and darkness even during the day, allowing for greater activity and damage by armyworms.
- 2). Check apple trees regularly for armyworm damage, including ragged holes in leaves, pellet-like droppings and the surface of apples eaten away. Also check for armyworms themselves, which are 1/2 to 2 inches long and green to black in color with a Y-shaped marking on their heads.
- 3). Clear the debris under the apple trees. During the day, the armyworms drop off of the trees and burrow in the soil; the more debris under the trees, the easier it is for the armyworms to hide.
- 4). Rely on armyworms' natural predators, including beetles, ants and spiders, to limit their population. Insecticides can do more harm than good by killing these and other beneficial insects, leaving your apple trees vulnerable to another pest outbreak with no natural predators to protect them.
- 5). Apply pesticides, but no more than is necessary to kill the armyworms, if the damage to your apple trees exceeds 15 percent of the growth. This amount of damage is serious and is cause for more drastic action to avoid further damage that could result in a lost crop.
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