Timothy is a perennial bunch grass that has a shallow, fibrous root system that does not spread by rhizomes or stolons. Timothy is readily identified by its characteristic cylindrical seed head, blue-green color, and swollen tiller base. Individual timothy shoots live during parts of two growing seasons, and some new shoots develop each year from older ones, which results in a perennial stand.

Timothy hay is an increasingly popular grass hay, highly favored by horse owners around the globe. In addition to being the premium forage for horses, timothy is highly popular for dairy cows and other livestock. In Japan, for example, timothy is the preferred forage for high producing dairy cows because of its palatability, consistency of texture, and impact on rumen stimulation.

The timothy plant prefers a slightly damp, moderate climate with cool evenings and warm days. If growing conditions are too warm, the timothy plant develops a coarse stem by increasing the amount of lignin in the plant cell structure. Overly coarse stems may cause the hay to become unpalatable to some livestock, especially high producing dairy cows.