Principles of Turfgrass Growth and Development
A comparison to trees illustrates the dynamic nature of the turfgrass ecosystem. Mowing stimulates production of new tillers and new leaves. Vertical mowing, dethatching and slicing are practices designed to rejuvenate turfs. Even the predominant effect of nitrogen fertilizer is not in greening up existing leaves, but stimulating growth of highly visible, new juvenile leaves that are greener than old aging leaves. The two major seasonal environmental factors controlling turfgrass growth are temperature and rainfall. The two basic types of turfgrasses are adapted to warm and cool climates and exhibit seasonal growth patterns related to that climate. Cool-season grasses in the cool humid region of the US exhibit a typical growth pattern. Warm-season grasses exhibit peak vegetative growth during the summer. Growth of cool-season grasses is complicated by growth habit responses to long and short daylengths, and latent responses to cold temperatures (seedhead vernalization).