Pearleaf blister mite
Editor’s note: This article is from the archives of the MSU Crop Advisory Team
Alerts. Check the label of any pesticide referenced to ensure your use is
included.
Bob
Bricault, an MSU Horticulture educator in Washtenaw County, received
several samples of ornamental pear leaves last week that were covered
with brown spots on the undersides and blistered on the tops. Bob diagnosed the problem as pearleaf blister mite, a microscopic mite
that causes these symptoms. Most of the time the injury is minor and
nothing to worry about, but occasionally nearly every leaf turns brown.
The only published control strategies for this mite is to plant
resistant cultivars of ornamental pear, or to spray with infested trees
with a horticultural oil in April before the buds begin to swell.