Corn Gluten Meal

Corn Gluten Meal
Effect:Pre-emergent
Selectivity:Small-seeded weeds
Persistence:5-6 weeks[1]
Application:Granular dust, generaly applied with drop or broadcast spreaders
Action:Inhibits root formation
Ecological hazards:very low risk
Organic Gardening:Acceptable

Corn Gluten Meal (often simply called CGM) is a byproduct of corn (maize) processing that has historically been used as an animal feed, but was discovered to have pre-emergent herbicidal effects in 1985, by Dr. Nick Christians, during a turf grass experiment being conducted by Iowa State University[2].

The use of corn gluten meal as an herbicide is patented[2], but like many food-related substances used for gardening is not regulated in the US [3]

Uses edit

Target plants include primarily small-seeded annual and perennial herbs. It is most frequently used in lawns[4], but may be applied to gardens and fields as well.

The corn gluten meal breaks down over time as an organic nitrogen source (NPK value of 10-0-0).[1]

Action edit

Proteins in CGM inhibit root formation on newly germinated seeds, killing the plant. Applications must be timed so that the CGM is present and effective as seeds are germinating.

Application edit

Applied using a spreader or even by hand (the material is pretty much harmless if not inhaled, and in fact is edible but not particularly palatable).

On lawns, CGM is applied in early spring (usually timed phenologically by the blooming of Crocus or Forsythia), and again in the autumn. If the lawn is overseeded, CGM should either be applied at least 6 weeks before sowing, or 2 weeks afterwards.

Precautions edit

Very safe to use, non-toxic[4]. Should not be applied to areas where it's likely to wash directly into watersheds (it is a nitrogen source), but otherwise ecologically safe.

Resistance edit

Large-seeded weeds seem unaffected.

Species affected edit

Testing for affected species is ongoing, but confirmed species include[5][6][1]:

References edit

  1. a b c "Turf:Corn Gluten Meal". Retrieved 2006-12-09.
  2. a b "Corn Gluten Meal Research Page". Retrieved 2006-12-09.
  3. "EPA Federal Register". Retrieved 2006-12-09.
  4. a b "EPA Fact Sheet". Retrieved 2006-12-09.
  5. "CNRS abstract (greenhouse tests)". Retrieved 2006-12-09.
  6. "CNRS abstract (field tests)". Retrieved 2006-12-09.

External links edit