Oil down that hedge

kw: gardening, hedges, pests

This little mite, seen here in an image from Branching Out at Cornell, bedevils privet, camellia and similar plants. It takes a strong magnifier or microscope just to see them; they are less than a quarter of a millimeter long (about 1/100 inch). Eryophyid mites are unusual in having only four legs. They crawl very slowly and some call them "worm mites", but they are smaller than even the tiny C. Elegans nematode.

I have about 400 feet of privet hedge, and though I sprayed with oil last fall, I see signs of privet rust mite damage. So I bought two quarts of horticultural oil today, and I plan to spray both sides of all the hedge plants tomorrow. Fortunately, this oil is not toxic, just a bit messy. It smothers the little critters.

Last fall, shortly after spraying, I cut back the hedge on one side where it fronts a sidewalk, that it was overlapping rather seriously. The open side is beginning to fill in with new growth, so this is the perfect time to spray through the hedge to the back side of the leaves on the other side.