Q: Some of my camellias are not looking their best. The leaves of a few of them are brownish-gray. Can you help me?
Q: Some of my camellias are not looking their best. The leaves of a few of them are brownish-gray. They seem to have specks of something all over them but I can not tell exactly what they are. Can you help me?
A: I am glad you brought in a few samples as the brownish coloration on the leaves could be caused by several things. After viewing the leaves under the scope we were able to determine the cause of the bronzing was from hundreds of two-spotted mites feeding on the leaves. The two-spotted spider mite prefers the hot, dry weather of the summer and fall months, but may occur anytime during the year. Overwintering females hibernate in ground litter or under the bark of trees or shrubs.
This mite has been reported to infest over 200 species of plants. Some of the more common ornamental plants attacked include arborvitae, azalea, camellia, evergreens, hollies, ligustrum, pittosporum, pyracantha, rose, and viburnum. Fruit crops attacked include blackberries, blueberries, citrus and strawberries. A number of vegetable crops such as tomatoes, squash, eggplant, cucumber are also subject to two-spotted spider mite infestations and damage. The mite is also a pest of trees and may damage maple, elm, and redbud. Complete defoliation may occur if the mites are not controlled. You may need to use a spray program of horticulture oil in addition to an ornamental miticide specifically labeled for ornamental trees and shrubs