Corn gluten meal applicator for weed control in organic vegetable production

Authors: Webber Iii, Charles; SHREFLER, JAMES - OSU, LANE, OK

Submitted to: Journal of Vegetable Crop Production
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/4/2005
Publication Date: 8/1/2007
Citation: Webber III, C.L., Shrefler, J.W. 2007. Corn gluten meal applicator for weed control in organic vegetable production. Journal of Vegetable Crop Production. 12(4):19-26.

Interpretive Summary: Weeds are often mentioned as the most troublesome problem facing organic vegetable producers. Corn gluten meal (CGM) is an environmentally friendly material that has demonstrated ability to decrease seedling development and plant survival by inhibiting root and shoot development. Unfortunately, CGM can also decrease the development and plant survival of direct seeded vegetable crops. The development of a mechanized method for CGM application and the ability to apply the material in a banded pattern would increase its potential use in organic vegetable production, especially in direct seeded vegetables. The objective of the research was to develop a method to uniformly apply CGM to the soil surface in either a solid (broadcast) or banded pattern. An applicator was assembled using various machinery components (fertilizer box, rotating agitator blades, 12-volt motor, and fan shaped gravity-fed row banding applicators). The equipment was evaluated for the application of two CGM formulations (powdered and granulated), three application rates [5, 10, and 15 lb/100 ft2 (250, 500, and 750 g/m**2)], and two application configurations (solid and banded). Field evaluations were conducted during the summer of 2004 on 32-inch (81 cm) wide raised beds at Lane, OK. Differences between CGM formulations affected the flow rate within and between application configurations. The granulated formulation flowed at a faster rate, without clumping, compared to the powdered formulation, while the CGM in the banded configuration flowed faster than the solid application. It was determined that the CGM powder used with the solid application configuration was inconsistent, unreliable, and thus not feasible for use with this equipment without further modifications. These evaluations demonstrated the feasibility of using equipment, rather than manual applications, to apply CGM to raised beds for organic weed control purposes. A number of equipment alterations will increase the efficiency and potential usefulness of this equipment. If research determines equivalent weed control efficacy between the two CGM formulations, the granulated formulation would be the preferred formulation for use in this equipment. This equipment would be useful for evaluate the benefits of banded applications of CGM for weed control efficacy and crop safety for direct seeded vegetables.

Technical Abstract: Producers of organic vegetables often report that weeds are their most troublesome production problem. Corn gluten meal (CGM), a by-product of the wet-milling process of corn, is phytotoxic. As a preemergence or preplant-incorporated herbicide CGM inhibits root development, decreases shoot length, and reduces plant survival of weed or crop seedlings. The development of a mechanized application method for CGM and the ability to apply the material in a banded pattern would increase its use in organic vegetable production, especially in direct seeded vegetables. The objective of our research was to develop a mechanized method to uniformly apply CGM to the soil surface in either a solid (broadcast) or banded pattern. An applicator was assembled using various machinery components (fertilizer box, rotating agitator blades, 12-volt motor, and fan shaped gravity-fed row banding applicators). The equipment was evaluated for the application of two CGM formulations (powdered and granulated), three application rates (250, 500, and 750 g/m**2), and two application configurations (solid and banded). Field evaluations were conducted during the summer of 2004 on 81-cm wide raised beds at Lane, OK. Differences between CGM formulations affected the flow rate within and between application configurations. The granulated formulation flowed at a faster rate, without clumping, compared to the powdered formulation, while the CGM in the banded configuration flowed faster than the solid application. The CGM powder used with the solid application configuration was inconsistent, unreliable, and thus not feasible for use with this equipment without further modifications. These evaluations demonstrated the feasibility of using equipment, rather than manual applications, to apply CGM to raised beds for organic weed control purposes. A number of equipment alterations will increase the efficiency and potential usefulness of this equipment. If research determines that the weed control efficacy between the two CGM formulations is equivalent, the granulated formulation would be the preferred for use in this application equipment because it flows more smoothly. This equipment would be useful for evaluating the benefits of banded applications of CGM for weed control efficacy and crop safety for direct seeded vegetables.