Pre-Tillage Control of Spear Grass (Imperata Cylindrzca [L.] Raeuschel) with Glypnosate for Soya Bean (Glycine Max [L.] Merr.) Production in Nigeria

Spear grass jImperata cyclindrica) is among the world's most important weeds (Holm, 1969) and the most common weed that attacks soya bean in Benue State of Nigeria (Avav et al., 1995). Benue State produces 90% of the total soya bean produced in Nigeria (Anon 1990). Growth and development of spear grass are encouraged by annual bush burning (Akobundu and Agyalcwa, 1987; Terry and Michieka, 1987) in the study area. The customary control of I. cylindrica by smallholder farmers in the study area is by hoeing which tends to promote the propagation of the weed. The weed is however, controlled by regular hoeing which is labour intensive and costly.