Root-knot nematodes are only 1/50" long, with thin, translucent bodies. Occurring naturally in large numbers throughout the U.S., especially in the Southeast, they plague vegetables, ornamental plants and trees. Infested plants are usually stunted, lighter in color and lower in yield than healthy plants. Roots have swellings, galls or knots in which the nematodes live. They rob the plant of food and make root crops such as carrots unsightly or completely unusable.
Beneficial Sf Nematodes provide excellent control of root-knot nematodes. Cultural practices are also important. Soil rich in organic matter is a favorable environment for fungi, some of which control plant-attacking nematodes. Maintain a high humus content in garden soil by adding compost and growing a cover crop to turn under in spring. (Root-knot nematodes enter the roots of rye and are trapped and destroyed when the rye is turned under.)