Honeydew
What is the white material on a tree twig?
It is possibly honeydew excreted by aphids as a sugary waste. Some (spirea, willow twig, white pine) occur in the spring. Others (crape myrtle, giant bark, willow leaf, linden, maple, and oak) build up in mid-summer. Many (white pine aphid) may be present, migrating to hosts throughout the season and in the fall. Apply control measures before populations become large. Aphids may infest buds, leaves, stems, branches, or trunks of the host plants. Be sure to follow all label directions and precautions. Horticultural oil or soap may be used. Ask your Extension agent for information about appropriate pesticides. Soaps and oils are most effective when used when large numbers of over wintering eggs are detected. Again, it is often best to leave control of aphids to natural predators to minimize damage to host plants.
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