Nalepella, the rust mites, is a genus of very small Trombidiform mites in the family Phytoptidae. They are commonly found on a variety of conifers, including hemlock, spruce, balsam fir, and pine. They sometimes infest Christmas trees in nurseries. Nalepella mites are vagrants, meaning they circulate around the tree; females overwinter in bark cracks. Infested spruce emit a characteristic odour.

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