Using Science to Enrich Beautiful Landscapes
Arborvitae do very well in Michigan so long as there are no deer in your area. Deer are considered the biggest threat to this plant because of the winter feeding damage that is done in order to survive above blankets of snow. A good deer repellent like Deer Pro or Deer Scram are best to limit the feeding activity of deer throughout the winter.
Another pest associated with this plant is the spider mite. Spider mite damage on Arborvitae can be observed by noting a tannish color of the needles. Sometimes their infestation is so heavy that fine webbing can be observed on the branches. To confirm simply take a piece of paper and tap the foliage while holding the paper beneath. Gently tip the paper knocking off any debris then swipe you hand across the sheet and you may witness red, orange and brown smears. These were the spider mites you just identified as the pest. It is important to know that any bright red spider mites seen with the naked eye moving quickly on the sheet of paper or observed on any patio walks and walls are the predator mites that feed on spider mites so they should be understood as beneficial insects.
Posted on: August 4, 2015
What you’ll see…is wilting leaves and dieback of branches, often one at a time or on one side of the tree. This can occur over a number of years, with remiss...