Giant bark aphid is the largest aphid in North America. This sap feeder can live on several tree species. Winged forms disperse from tree to tree. Wingless aphids occur in large colonies. These aphids produce a large amount of sticky liquid waste, honeydew, which drips onto objects below. Feeding by large numbers of these aphids can damage or kill small twigs. They are eaten by lady beetles and other predators. Photo: Herbert A. 'Joe' Pase III, Texas A&M Forest Service, Bugwood.org Spittlebugs are small, sap-feeding insects that live in white, foamy masses resembling spit on buds, tender shoots, or nutlets. The liquid provides a high humidity environment and may give protection from natural enemies. Spittlebug adults, which resemble light brown leafhoppers, are active about mid-May. Photo: Bill Ravlin, Michigan State University, Bugwood.org Cottony cushion scale is an invasive scale species that can be found feeding on the sap of numerous species of plants. Adult females are orange-brown but coated with white wax and will have a long, fluted egg sac attached to the body. This can contain up to 1,000 eggs. After hatching, the nymphs (which are red with dark antennae and legs) will seek a suitable space for feeding. Nymphal feeding on leaves can cause extensive damage and honeydew/black sooty mold will accumulate as the population builds. Photo: Sturgis McKeever, Georgia Southern University, Bugwood.org Greedy scale are small armored scales that create a conical shaped cover. As they grow and shed their old exoskeleton, it is incorporated into the wax that makes up the shield. Eventually this results in a characteristic off-center nipple or dot on the outer coating. There are often concurrent overlapping generations on plants. United States National Collection of Scale Insects Photographs, USDA Agricultural Research Service, Bugwood.org Walnut lace bugs feed on black walnut trees by sucking sap from leaves. They typically feed on the undersides of leaves and cause discoloration. Leaves will have yellow stippling and lace bug frass resembles droplets of motor oil. They feed throughout the summer and damage is most noticeable by autumn. They are 1/8 to 1/3 inch long and their wings and thorax have a lacy, doily-like appearance. Photo: Whitney Cranshaw, Colorado State University, Bugwood.org

Spittlebugs are small, sap-feeding insects that live in white, foamy masses resembling spit on buds, tender shoots, or nutlets. The liquid provides a high humidity environment and may give protection from natural enemies. Spittlebug adults, which resemble light brown leafhoppers, are active about mid-May. Photo: Bill Ravlin, Michigan State University, Bugwood.org

Cottony cushion scale is an invasive scale species that can be found feeding on the sap of numerous species of plants. Adult females are orange-brown but coated with white wax and will have a long, fluted egg sac attached to the body. This can contain up to 1,000 eggs. After hatching, the nymphs (which are red with dark antennae and legs) will seek a suitable space for feeding. Nymphal feeding on leaves can cause extensive damage and honeydew/black sooty mold will accumulate as the population builds. Photo: Sturgis McKeever, Georgia Southern University, Bugwood.org

Greedy scale are small armored scales that create a conical shaped cover. As they grow and shed their old exoskeleton, it is incorporated into the wax that makes up the shield. Eventually this results in a characteristic off-center nipple or dot on the outer coating. There are often concurrent overlapping generations on plants. United States National Collection of Scale Insects Photographs, USDA Agricultural Research Service, Bugwood.org

Walnut lace bugs feed on black walnut trees by sucking sap from leaves. They typically feed on the undersides of leaves and cause discoloration. Leaves will have yellow stippling and lace bug frass resembles droplets of motor oil. They feed throughout the summer and damage is most noticeable by autumn. They are 1/8 to 1/3 inch long and their wings and thorax have a lacy, doily-like appearance. Photo: Whitney Cranshaw, Colorado State University, Bugwood.org