Boxwood Mite
Eurytetranychus buxi
A tiny spider mite specific to boxwood that feeds on the leaves and stipples them with fine scratch-like marks. Heavy populations bronze and discolor the foliage and can cause leaf drop, with the worst damage on plants in full sun.
🔎 How to spot it
Adults are greenish to yellowish brown, have eight legs, and are tiny, only about one sixty-fourth of an inch long, so a hand lens is needed to see them. The eggs are laid on the undersides of the leaves. The first sign is fine stippling and tiny scratch-like yellow spots on the upper leaf surface.
🥀 Damage it causes
Feeding produces fine stippling on the upper leaf surface and tiny scratch-like yellow marks caused by the toxic saliva, giving leaves a dull, speckled, hen-scratched look. As feeding continues the foliage bronzes and discolors, and heavy infestations can lead to premature leaf drop. English and American boxwoods in sunny, dry sites are the most affected.
🛡️ Prevent it
Inspect boxwoods in spring and early summer, checking leaf undersides for mites and eggs, since the pest breeds rapidly once warm. Keep plants healthy and not drought-stressed, and avoid broad-spectrum insecticides that kill the predators that help suppress mites. Hosing down the foliage can reduce light infestations.
🧯 If it is already here
Apply horticultural oil at the labeled summer rate to kill eggs and mites, and use insecticidal soap before populations get high, treating early in the season on plants that showed heavy feeding the year before. Repeat applications may be needed because many generations occur. Good coverage of the leaf undersides improves results.
💡 Good to know
The boxwood mite overwinters as eggs on the undersides of leaves and can produce eight or more generations a year, so it builds quickly in warm weather. It feeds only on boxwood. Sun-stressed plants show the most injury, so siting and vigor matter as much as spraying.
🌱 Plants it attacks
178 plants in the library can be attacked by this pest
CalibrachoaFor educational and informational purposes only. Pest control advice is general guidance drawn from university cooperative extension sources; always identify a pest positively and read and follow the label on any product before use, especially around food crops, children, and pets.