A Few of Mites Can Weave a Web of Intrigue

During the winter months, mites can cause damage to both cool and warm season turfgrasses months. Their needle-like mouthparts pierce the plant or leaf sucking out the plant juices. Although mite damage for the most part is sporadic, symptoms can appear speckled with a purplish shade or a bleached straw color. Severely damaged plants may appear stunted or killed. A potential sign of mite damage occurs in early spring when the turf fails to green up.

Most mites are no larger than a period at the end of sentence. Adult mites have 8-legs versus the 6-legs typically associated with insects. This is one reason that mites are more closely associated with spiders than to insects. The term spider mite is often used as an umbrella term for several different types of mites that may have not been specifically identified.

Of the many mites a few produce significant and large scale webbing.

Without proper identification, it is difficult to tell the mite species, but two types of mites, the Banks grass mite and the Australian redlegged earth mite are copious web formers. The Banks grass mite, sometimes referred to as a true spider mite, can attack both
cool and warm season turfgrasses including couchgrass and seashore paspalum. The Australian redlegged earth mite is associated with more temperate climates like those found in southern Australia. The winter grain mite found in the United States is a close relative of the Australian redlegged earth mite.

The life cycle of mites consists of several stages including the egg, larva (when newly hatched contain three pairs of legs), nymphs,
and adults. During winter (late fall through early spring) turf infestation eggs and the various stages of development are often present
at the same time. Control of mites is very difficult. Several mites are immune to many of the turf insecticides.

Photograph 3: Winter grain mites (close relative of the Australian Redlegged Earth Mite).