Sooner or later, diseases, insects, extreme heat or cold, drought and saturated soils may severely damage turf. For example, each spring, Rhizoctonia fungi are responsible for patches of injured plants observed in bermudagrass, tall fescue and Zoysia. White grubs, the larvae of scarab beetles, feed on roots. Fescues and Kentucky bluegrass plants may die in summer when leaf temperatures reach 100 degrees Fahrenheit or more. Bermudagrass, centipedegrass, St. Augustinegrass and Zoysia are dormant and prone to low temperature injury in winter. Excessively dry soils resulting from extended periods of drought do not provide adequate amounts of water or essential nutrients. Too much water may accumulate on sites with poor surface or subsurface drainage. Roots of turfgrasses growing in saturated soils often die from a lack of oxygen.

Improper mowing, fertilization or pesticide application may also damage turf. Removing too many leaves when mowing severely reduces the amount of leaf surface exposed to sunlight. As a result turfgrasses may lose energy and be less able to compete with weeds such as crabgrass and goosegrass. Routine scalping results in poorly rooted turfs that are prone to drought and high or low temperature injury. Soils seldom provide plants with enough nitrogen, and may also be low in phosphorus and potassium. Turfs in need of fertilization are often thin and disease prone. However, applying too much fertilizer at one time can increase the salt concentration of the solution surrounding roots and cause plants to dehydrate and die. The mis-application of a fungicide, herbicide or insecticide is often toxic to turfgrasses as well as troublesome pests.