Hemlock woolly adelgid, or HWA, is member of the Sternorrhyncha suborder of the Order Hemiptera and native to East Asia. It feeds by sucking sap from hemlock and spruce trees

The gypsy moth is one of North America’s most devastating forest pests. The species originally evolved in Europe and Asia and has existed there for thousands of years. The gypsy moth is known to feed on on the foliage of hundreds of species of plants in North America but its most common hosts are oaks and aspen. Gypsy moth hosts are located through most of the US.

The pine sawfly can be very destructive, attacking trees 1 foot to 12 feet tall. Infestations may be worse on trees already under stress due to a poor site or if under severe competition from other trees. Some species change significantly in appearance as they grow, making identification confusing. Large numbers of sawflies can strip the needles from a tree in a short period.

Both adults and nymphs suck plant sap, which usually causes distorted leaves, buds, branch tips, and flowers. Severely infested leaves and flowers may drop. As they feed, aphids excrete a sweet, sticky honeydew onto the leaves below. This allows a sooty mold to grow, which, in addition to being ugly to look at, blocks light from leaves. Also, some aphids spread viruses as they feed.

Spider mites, almost too small to be seen, pass into our gardens without notice. No matter how few, each survives by sucking material from plant cells. Large infestations cause visible damage. Leaves first show patterns of tiny spots or stipplings. They may change color, curl, and fall off. The mites activity is visible in the tight webs that are formed under leaves and along stems

Various types of leafminers attack various kinds of plants. They’re found on broadleaf trees, including elm, aspen, hawthorn, and poplar as well as shrubs and bushes, including lilacs. Damage can be limited in initial stages of infestations but increase as leafminer numbers multiply, and even minor infestations, while not killing a plant, will cripple its hardiness.

The female moth lays her eggs on branches of coniferous and deciduous trees in the fall. The larvae eat the vegetation while creating a pouch around itself. This pouch is made up of the host plant’s vegetation and is why the bagworm is such a destructive pest. In the past, the only choice a gardener had was to either spray with a chemical or hand pick off the bags. Today, we use organic methods to deal with bagworms.