Abstract: Crop yields are significantly enhanced by treating soil or other plant growing media with a fungicidally or pesticidally effective amount of metham, the fungicidally or pesticidally effective amount being insufficient to significantly retard growth of a plant. In the practice of the invention, the soil or growing media surrounding roots of growing plants is treated with metham by dripping an aqueous solution of metham onto the media, by injecting the aqueous solution into the soil, by irrigating the soil or by drenching or spraying the soil with the aqueous solution. Significantly reduced amounts of metham are employed to reduce damage to the plant or vegetative material.

Abstract: Crop yields in a plant bed are significantly enhanced by treating soil in the plant bed with a fungicidally effective amount of metham, the fungicidally effective amount being insufficient to retard growth of a plant. In the practice of the invention, the plant soil is treated with metham by dripping an aqueous solution of metham into a seed furrow, by injecting the aqueous solution into the soil or by drenching the soil with the aqueous solution, either at about the time of planting of the seed or vegetative material or by treatment of the soil surrounding established plant crops. Significantly reduced amounts of metham are employed to reduce damage to the planted seed or vegetative material.

Abstract: Perennial weeds are controlled by deeply placing selected volatile chemical soil fumigents, 14 to 24 inches below ground level, at 18 to 30 inches of horizontal spacing, and applied at rates ranging between 2.5 to 30 gallons per acre, to destroy their vegetative and reproductive roots. Examples of such perennial weeds that are effectively and economically controlled and/or eliminated are morning glory, which is also called field bindweed or Convolvulus arvensis and Canadian thistle, which is also called Cirsium arvense. Examples of the volatile soil fumigants are respectively: 1-3 dichloropropene and related chlorinated C 3 hydrocarbons containing fumigants known by various marketing names and symbols, such as Telone, Vidden-D DD, 1-3 D, and Vorlex; Methyl bromide contaning fumigants known as M. B.; and/or ethylene dibromide containing fumigants known as E.D.B.