Plant parasitic nematodes are microscopic, translucent roundworms, generally 0.5 to 3 mm in length, depending on the species. All are vermiform (wormlike) at least during the early stages of their life cycles. Most nematodes have well developed digestive and reproductive systems.
Surface symptoms of nematode injury may include a slow green-up in spring, chlorosis and dieback of the leaf blades, sensitivity to stresses, reduction in vigor, stunting, and gradual thinning of the turf sward. Symptoms usually occur in gradually enlarging circular to irregular areas because of the clustered distribution of nematodes.