Scale insects are one of the most undesirable bugs to visit your trees and shrubs. Scale insects look very different from most other insects and are often missed when trees and shrubs are infected with them. Scales look like little white, gray, or brown bumps on stems and are found on almost all kinds of fruit shade and evergreen trees. Scales suck the juices from the stems, which causes the leaves to become discolored and then wilt. The plant will eventually die if the scales go unnoticed for very long. There are two main types of scale insects, which are the soft bodied scales and the hard bodied scales. A few of the more common scale insects are the pine tortoise, pine needle, Fletcher, spruce bud, cottony maple, brown elm, European Elm, scurfy, peony, soft brown, San Jose, tea, euonymus, Florida wax, oleander, and thread.

Scales are difficult to get rid of once they invade your trees and shrubs. The shell, made up of wax-like fibers, protects the soft bodied insects inside from almost all forms of chemical controls. The best scale control is to encourage beneficial insects to make a home in your garden. They’ll feed on young scales before they form their shell, and will sometimes pierce the shell and lay eggs that will feed off the adult scale. It takes a few weeks for the beneficial insects to build up their population enough to control the pests. Some common beneficial insects are garden spiders, green lacewings, ground beetles, bees, hornets, wasps, yellow jackets, hoverflies, and lady bug beetles. You can also plant some things in and near the garden to bring in the beneficial insects, as well, like fennel, dill, Queen Anne’s Lace, lemon balm, and parsley. Also plant flowers like marigolds, salvias, alyssum, and candytuft. Control ants in your garden as well, as ants tend scales, aphids, and mealy bugs by interfering with their natural predators.

Even though you try these methods first, there may be times you have to resort to stronger controls. General control uses two types of spray mixtures – dormant spray and a summer spray. The dormant spray is applied in early spring before growth begins. Summer spray, of course, is used in the summer when growth is at its height. It should be applied once a month throughout the summer. First try using low impact insecticides like insecticidal soap, horticultural oil, and Bacillus Thuringiensis (BT). Derris, pyrethrum, and insecticidal soaps are organically approved and made from plant extracts. Other controls that have been used in the past are Diazon, Malathon, and Carbaryl. Always remember that the stronger controls you use will also kill beneficial insects as well, so always try the least measure first.