Mites
General recommendations. Minute red, black or brown mites are closely related to spiders, hence their common label of "spider mites." They attack just about anything in your flower or vegetable garden, including fruit crops. They especially like cucurbits, beans and tomatoes. In addition, plants on the inside of your house often fall victim to the indiscriminate mite. Mites feed on plants by sucking out plant juices, leaving leaves stippled, yellow and dry, or with pale yellow spots or blotches. They also suck chlorophyll out of leaves, causing small white dots to appear. Finally, they inject toxins into the leaves, discoloring and distorting them. If you notice any of the above symptoms, or fine webbing covering leaves, shoots and flowers, your plant is probably infested with mites. Since they are almost invisible to the naked eye, you can confirm your suspicion through examination of the undersides of the leaves with a magnifying glass. Tap a few leaves or a small branch tip against a sheet of white paper and look for the tiny culprits crawling on the paper.

Since mites thrive in hot, dry conditions, light infestations can usually be controlled simply with water, sprayed forcefully on the affected plant every other day in the early morning, beginning as soon as the first stippling of leaves is detected. Make sure you spray the undersides of the leaves, and wash plants at least three times. If mites persist or infestation is heavy, spray with insecticidal soap every 3 to 5 days for two weeks; for fruit trees, a mixture of insecticidal soap and a light horticultural oil is effective. Severely infested plants or infested portions may require destruction and disposal, since its hard to rein in a mite infestation once it's well underway.

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Clover mite (Acari)