NEMATICIDE. A chemical agent that kills, inhibits, or protects against nematodes.

NEMATODE. A tubular, unsegmented, roundworm, generally microscopic, usually living free in moist soil, water and decaying matter or as parasites of plants or animals.

NITRIFICATION. The process through which nitrites are converted to nitrates by soil bacteria.

NODE. The portion of a stem where leaves and buds arise.

NONSELECTIVE. A type of weed control that kills plants without regard to species.

NYMPH. An immature stage of bugs i.e. leafhoppers, aphids, and chinchbugs.