Dynaweed, a new pre-emergent herbicide, is made from a by-product of corn milling.

Soil Technologies Corp., Fairfield, IA, makes the herbicide by processing leftover corn gluten into a pellet form for spreading.

Corn gluten attacks the feeder root development of germinating seeds - including weed, corn and vegetable seeds. Thus, its value is as a herbicide for perennial crops like blueberries, asparagus and strawberries.

An added benefit: It contributes nitrogen to the soil.