The eggs are laid on and around bud scales and at the bases of needles. Unlike two-spotted mites, spruce spider mites are most active and damaging during the spring and fall when the temperatures are cooler and rainfalls are more frequent. These are also the best times to control spruce spider mites. Their activity and the effectiveness of control greatly decrease during hot summer weather. Older needles are attacked first, so the earliest injury is usually seen on the lower and inner parts of trees.
Infestations can spread to the top portions of trees as the season progresses.
If a miticide is warranted, select the least toxic material whenever possible and be sure to achieve good spray coverage on the undersides of leaves or needles. Read the miticide label carefully and make sure that the plant to be treated is listed on the label. Beneficial mites may also be purchased and released to aid in the control of pest mites. The information in this material is for educational purposes. The recommendations contained are based on the best available knowledge at the time of printing.