Other ways to manage weeds

Livestock: Intensive rotational grazing is widely recognized for its effectiveness in limiting perennial weeds in pasture. But in some specialized systems, farmers have developed additional ways to use livestock for weed management. Chickens confined to small pens and rotated through fields have been shown to be effective at eradicating yellow nutsedge. Geese preferentially eat grasses, and so can be used to weed strawberry fields without damaging the crop. Some tree-crop farmers use sheep to graze the alleys between rows of trees or coffee bushes.   

Organic herbicides: Very few input products are available for organic weed management. Corn gluten meal has use as a fertilizer (10% N) as well as an herbicide, but to be permitted in organic farming it must be made from non- GMO corn. It is prohibitively expensive for most crops, although it may have uses in greenhouse or specialty crop systems.   

Other organic-approved herbicides on the market are vinegar-based, like Matran, a vinegar-clove product. To be effective, concentrations in the range of 10 to 12% acetic acid are needed, although lower concentrations may work on small annual weeds. For organic use, the acetic acid must be derived from natural fermentation—industrial acetic acid is not permitted. At these concentrations, acetic acid is legally required to be labeled as a pesticide, which limits the number of products available.

Always check the OMRI list and consult with your certifier before investing in a new input material.   

 
Night-time tillage: Some farmers and researchers are experimenting with night tillage using infrared goggles. Weed species such as lambsquarters, ragweed, pigweed, smartweed, mustard and nightshade require just a fraction of a second of light to trigger germination. The idea of night tillage is to eliminate that trigger.