Chemical used in the form of a volatile liquid or a gas to kill insects, nematodes, fungi, bacteria, seeds, roots, rhizomes, or entire plants; usually applied in an enclosure of some kind or in the soil with a plastic or water surface seal.
Botanically, any plant of the Gramineae family. Grasses are characterized by narrow leaves with parallel veins; by leaves composed of blade, sheath, and ligule; by jointed stems and fibrous roots; and by inconspicuous flowers usually arranged in spikelets.
Water that contains certain minerals, usually calcium and magnesium sulfates, chlorides, or carbonates in solution in sufficient amounts to cause a curd or precipitate instead of a lather when soap is added. Generally defined as water containing 332 ppm of calcium carbonate. Very hard water may cause precipitates in some herbicidal sprays.