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Beneficial Nematodes

Nematodes are tiny worm-like organisms, most of which are found living naturally in soil. They attack and kill soil-dwelling and boring insects such as weevils, grubs, beetles, maggots and cutworms. Nematodes are desirable to use since they do not endanger people, pets or even earthworms. Using living, natural biological control agents sustains and augments the natural soil diversity while conserving other beneficial organisms that contribute to healthy soils.

The shelf-life of nematodes is about two to three months at 70 degrees and about 20 months in a normal refrigerator (35 degrees). Nematodes should be kept in a refrigerator until ready for use. Use the entire content of a package, since they may migrate to a single part of the container.

Application and Soil Conditions
Apply the nematodes away from direct sunlight. Keep the area moist for a few weeks after application to allow them to travel farther. The frequency of application depends upon the targeted pest species. Nematodes reproduce in many pests such as beetle grubs, providing a self-perpetuating population. They do not, however, reproduce in certain pests such as fleas, and may therefore need to be applied every few weeks. Typically, nematodes will not survive through the winter season.

Nematodes can safely tolerate a water/soil pH range of 5 to 9, but be careful using water with high sulfur content that can suffocate them. They are capable of being tank-mixed with many chemicals such as insecticides, fungicides, fertilizers and soil amendments.