1) Tulip tree aphid on tulip poplar                2) Woolly beech aphid on beech

APHIDS - Aphids, of the order Homoptera, are soft-bodied, pear shaped insects with piercing-sucking mouth parts. They can be a variety of colors and some exude a woolly covering. They produce sticky, sugary excrement called honeydew. Shiny, sticky spots on the leaves can be an indication of aphid infestation. They can reproduce rapidly and often form thick masses on stems. Aphids are vectors for a variety of diseases. Some aphid species feed on a variety of different plants while others stick to one particular host species. A wide variety of trees and shrubs such as ash, tulip poplar, pine and viburnum can be susceptible to aphids. They can also be a pest in greenhouses and on indoor house plants. For aphid control horticultural oil is applied when the aphids are first detected.