Author
Boyd, Nathan | |
Brennan, Eric | |
FENNIMORE, STEVEN - UC, DAVIS |
Submitted to: Weed Technology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/14/2006 Publication Date: 10/20/2006 Citation: Boyd, N., Brennan, E.B., Fennimore, S.A. 2006. Stale seedbed techniques for organic vegetable production. Weed Technology. V. 20. pg. 1052-1057. Interpretive Summary: Weed control in organic vegetable production systems is challenging and expensive. We compared six weed management techniques to prepare stale seedbeds in organic vegetable production. They included 1) a propane flamer, 2) a clove oil herbicide, 3) a sled with top knives, 4) a rolling cultivator, 5) a rotary hoe, and 6) a bed shaper-roto tiller combination. Weed control operations occurred on raised beds 2 to 3 days before planting baby spinach or a simulated vegetable planting. Broadleaf weed control was 36% with clove oil, 63% with the rotary hoe, and significantly higher (87-100%) with the other techniques at one site. Broadleaf weed control was consistently lower (72-86%) with the flamer than all other treatments (95-100%) at two other sites. The flamer and the clover oil herbicide had the lowest in-crop weed emergence but were the most expensive techniques at $228 and $1557/ha, respectively. The estimated cost of forming stale seedbed with the remaining weed management tools ranged from $195 to $214/ha. Technical Abstract: Weed control in organic vegetable production systems is challenging and accounts for a large portion of the production cost. Six organic compliant weed management tools used to prepare a stale seedbed were compared on certified and transitional organic land in Salinas, California, in 2004. Weed control operations occurred on raised beds 2 to 3 days before planting baby spinach or a simulated vegetable planting. A flamer using 24 kg/ha of propane and an herbicide application of 10% v/v of a clove oil mixture (45% v/v clove oil) at 280 L/ha (site 1) or 15% v/v of a clove oil mixture (45% clove oil) at 467 L/ha (site 2 and 3) were used to control weeds without disturbing the soil. Top knives on a sled, a rolling cultivator and a rotary hoe were used to control weeds while tilling the bed top. A bed shaper –roto-tiller combination was also used which tilled the entire bed. Broadleaf weed control was 36% with clove oil, 63% with the rotary hoe, and significantly higher (87-100%) with the remaining treatments at site 1. Broadleaf weed control was consistently lower (72-86%) with the flamer than all other treatments (95-100%) at sites 2 and 3. The flamer and the clover oil herbicide had the lowest in-crop weed emergence but were the most expensive techniques at $228 and $1557/ha, respectively. The estimated cost of forming stale seedbed with the remaining weed management tools ranged from $195 to $214/ha. |