One of the most common is aphids. Aphids are sometime called plant lice and are related to cicadas, leaf hoppers, whiteflies and scale insects. Aphids are sucking insects about one tenth of an inch long and can be winged or wingless. They are pear shaped and have soft bodies. Under magnification most aphids will have two small horn like structures protruding from their backs.
Aphids range in color from light green to dark brown and black.
Aphids cause damage by sucking the juices from the plant. Gathering in great numbers, aphids are most commonly found on the tips and stems of plants sucking the sap for nourishment. Aphids can also be found on the underside of foliage sucking, which leaves the leaf curled or puckered. The feeding by aphids results in a sticky liquid appearing on parts of the plants. This residue is often referred to as honeydew which can attract ants.