Weed populations and cultural practices on wheat farms of the Hanang complex in Tanzania
1988
Owenya, Z.J. | Makoko, B.R. | Moyer, J.R. (Selian Agricultural Research Inst., Arusha (Tanzania))
Mechanized wheat production in a monoculture began on the Hanag plains in northern Tanzania in 1968 at the Basotu farm. In 1986, wheat was seeded on 24,200 ha at seven farms. The main weed control method is to delay seeding until the middle of the rainy season. Herbicides are used when foreign exchange is available. In 1986, the dominant weeds were Setaria spp., mainly lovegrass (Setaria verticillata L.). The Setaria spp. population ranged from 0 to 420 shoots/m2 on fields in the two oldest farms while the average Setaria spp. density on farms established since 1980 was less than 3 shoots/m2. The densities of the other weed species on the Hanang complex were not influenced by the number of years (1 to 15) that wheat had been grown in monoculture. Several weeds that are resistant to 2,4-D were identified but there was no indication that these weeds were becoming a serious problem
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