Potential Weed Management Systems for Organic Peanut Production
Abstract Studies were conducted near Tifton, GA to develop weed management systems for organic peanut production. Trials in 2004 and 2005 evaluated row patterns (two levels), remedial weed control (four levels), and cultivation (three levels). Row patterns were wide rows (91 cm apart) and narrow rows (30 cm apart). Remedial weed control was early-season applications of clove oil, citric plus acetic acid, broadcast propane flaming, and a nontreated control. Cultivation regimes were 1X or 2X sweep cultivation and a non-cultivated control. The experimental sites had heavy natural infestations of annual grasses and broadleaf weeds. None of the treatment combinations effectively controlled weeds season-long and resulting peanut yields were poor. Annual grasses were particularly troublesome due to ineffective control from flaming and citric plus acetic acid. Clove oil was slightly more effective in controlling annual grasses than the other remedial treatments, but annual grass control was still unacceptable. Dicot weeds were not effectively controlled by mid-season, although clove oil and flaming controlled the seedling weeds early season. The lack of residual weed control by the remedial weed control treatments resulted in heavy weed infestations by mid-season. Poor control of annual grasses, no residual weed control, and high cost of remedial treatments indicates that these systems of weed management in organic peanut production are not suited to sites with heavy weed infestations.