Color of different aphids range from bright orange or red to dull gray. One common group, woolly aphids, produce an abundance of flossy, waxy threads that cover their bodies.
Aphids feed on plants by sucking plant sap from the leaves, twigs or stems of plants.
When abundant, aphids remove large quantities of sap, reducing growth and vigor of the plant. Aphid feeding on developing leaves also can produce leaf curl injuries. This is most frequently observed on snowball viburnum, honeysuckle, plum and ash. Most aphids also excrete large quantities of a sweet, sticky substance called honeydew. At times, excessive honeydew dropping from trees can be an extreme nuisance.