In this photo you can see a line of Arborvitae which are browning due to Mite damage. Mites are microscopic and they cannot be controlled by basic insecticides. Why? Because Mites are not insects, they are Mites. Products called miticides are necessary to control them. They are resilient little guys, so products need to be rotated from time to time to keep the Mites from building up a tolerance to them.
Mites multiply every 10 to 17 days. Within a few months there are literally millions and millions of them feeding. Mites overwinter and resume feeding the following year if left untreated, so treatment is necessary every year to protect certain trees and shrubs against them.
In our area Colorado Blue and Green Spruce and Arborvitae are the plants most devastatingly attacked by mites. If your Spruce trees or Arborvitae are browning internally you should consider treating them. For additional photos of Mite damage visit our page on Spruce Mites.
It is important to note that Mites DO NOT attack this year’s fresh new growth. They only attack older growth. So, don’t assume you don’t have Mites because this season’s new growth looks healthy. Next year that growth will be under attack as well.
If you think your trees and shrubs might be under attack from this or any problem, just give us a call. Evaluations, as always, are free!