Mites found on conifers – scout now for activity
Large numbers of mites have been found on several conifers species. Make sure you’re scouting fields for mite activity.
We are beginning to find a large number of several mite species active in Christmas tree plantations. These include Admes and eriophyid mites in Colorado blue spruce and Black Hills spruce, and spruce spider mites in Fraser fir. Christmas tree growers should be actively scouting fields, especially if trees had damage from mites last year.
If you suspect mite problems, perform a foliage check. Take a piece of white paper (eriophyid mites show up best on a black background), hold it under a branch suspected of having mites and strike the branch hard against the paper. This should dislodge the mites, and even though they are very small, you should be able to see the dark, oval spider mites against the white background, or the cream-colored eriophyid mites on the dark sheet. You can also use a good hand lens to look for mites on branches.
Michigan State University Extension has several articles to help you with mite identification and management options:
- Spruce spider mite management – Spruce spider mite management in Christmas trees for 2015
- Eriophyid mite management – Should you spray for eriophyid mites on spruce?
- Mite identification – Mites are becoming active on conifers