Our cool spring has been perfect for aphids this year. As a result they are showing up on all kinds of perennials, shrubs and trees. There are literally dozens of different kinds of aphids, many of which prey on particular plants. They are generally about a sixteenth- to an eighth-inch long, in colors of green, brown, purple, red and black. Some are shiny while others have a waxy, cottony covering. All of them have long thin legs, sucking mouth parts, long antennas, a pear-shaped body and a pair of tiny tubes that project from the bug’s posterior. They are most often found on the underside of the leaves, where they tap directly into a plant vein to suck sap.