By Tom Dudek, Michigan State University Extension
Broad mites are less than 0.3 millimeters – smaller than a period in font size 12 print – and infest several greenhouse crops, including African violet, ageratum, azalea, begonia, dahlia, gerbera, ivy, bedding impatiens, lantana, marigold, New Guinea impatiens, peperomia, snapdragon, torenia, verbena and zinnia. According to Michigan State University Extension, broad mites will damage flowers and foliage of begonia and cyclamen and bronze the lower leaf surfaces. Their toxic saliva causes twisted, hardened and distorted growth in the terminal of the plants (see photos below). This feeding injury will last for a long time even after the infested plant has been treated and the mites have died.
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