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Corn Gluten - The Natural Herbicide

Safe For Your Vegetables, Flowers and Lawn
In 1985, a research project began at Iowa State University, by award winning scientist Dr. Nick Christians. His experiments led to the development of Concern Weed Prevention Plus, a natural product for weed control made from 100% corn gluten meal. Corn gluten meal is a by-product of the wet-milling process and is sold as a feed material for cattle, poultry, and other livestock. It has been used in fish food, for commercial fish production, and is also a primary ingredient in many dog food products. Corn gluten meal is produced as a fine yellow powder and is pelletized for easier application to the soil.

Here's How It Works
The corn gluten meal in Concern Weed Prevention Plus inhibits root formation of germinating weeds. Without roots, the weed plants cannot get water, and soon die.

Learn Why We Call It Plus
Corn gluten meal is composed of 10% nitrogen. Nitrogen is a valuable plant nutrient responsible for the vivid green color of healthy plants. The nitrogen in Weed Prevention Plus is in a natural slow-release form. This means it becomes available to the plants over an extended period of time, so it will not burn your plants. Applying Weed Prevention Plus not only controls weeds, but contributes to healthier plants and soil. Plants need a complete, and complex, range of nutrients for optimum growth. Use your regular fertilizer along with Weed Prevention Plus without fear of overfeeding.

Research Data
Dr. Christians' original project was designed to study the effects of a fungal pathogen on grasses. Corn gluten meal was combined with a fungus organism and then applied to the soil of a new golf course green at the field research area. At the same time, adjacent field areas were treated with the same amount of corn meal without the fungus. The study area was then seeded with creeping bentgrass.While the fungal organism/corn meal combination did not have the reducing effect on the grass that was anticipated, the control plots that received only raw corn gluten meal did have very thin grass stands. Close observation showed that something in the gluten meal stopped normal root formation at the time of germination while shoot tissue developed normally. When the soil surface dried, plants that had not developed a root system simply died.Field tests established that corn gluten meal could be used to inhibit the establishment of annual weeds, such as crabgrass, that germinate into turf. In July 1991, U.S. Patent No. 5,030,268 was issued on the use of corn gluten meal as a natural preemergence herbicide, on turf. Following submission of new data resulting from new research, the original patent was reissued in April 1994 as U.S. Patent Re. 34594. This reissue expands the original claims to include uses in field crops, gardens, and other agricultural areas.

Species Affected 
Twenty-two plants species have been screened for susceptibility to corn gluten meal: black medic, black nightshade, buckhorn plantain, catchweed bedstraw, common lambsquarters, curly dock, dandelion, purslane, redroot pigweed, velvetleaf, annual bluegrass, barnyardgrass, creeping bentgrass, giant foxtail, green foxtail, large crabgrass, orchardgrass, quackgrass, shattercane, smooth crabgrass, wooly cupgrass, and yellow foxtail. Corn gluten meal significantly reduced plant survival, shoot length, and root development of all tested species.

Effectiveness
Applied at a rate of 20 lbs. per 1000 sq. ft. in both the spring and fall, corn gluten meal reduced crabgrass by 86% at the end of the first year; 98% at the end of the second year. Dandelion infestation was reduced 100% in plots treated for four years at the 20 lbs. per sq. ft. rate when applied in the spring and fall.There is no postemergence effect of corn gluten meal on weeds, grasses or plants. For optimum control apply Concern Weed Prevention Plus a few weeks before germination. Water in if there is no rain. Weeds without an established roots system need a drying out period of 2-3 days, in order to effectively kill the emerging weed.


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