Selective Grass Control with Siduron

Abstract

Doses of 1-(2-methylcyclohexyl)-3-phenylurea (siduron), sprayed on seeds of several forage, turf, and weed grasses on the soil surface killed some weed grasses without injuring many desirable grasses. Seeds of tolerant grasses mixed with an excess of a dry siduron formulation and stored for 12 months germinated without injury, but crabgrass (Digitaria sanguinalis (L) Scop.) and barnyardgrass (Echinochloa crusgalli (L.)) were killed during germination. Siduron eliminated seedling weed grasses from seedling perennial turfgrasses when applied on the soil surface or incorporated in the soil just before planting. When applied as a coating on seeds of turfgrasses at planting time, siduron controlled some annual weed grasses without injurying the turfgrasses. Herbicidal action appeared to be localized mainly in the grass roots and differed from that of 1,1-dimethyl-3-phenylurea (fenuron) and isopropyl carbanilate (propham) applied at equimolar doses.