Volunteer Corn Creates Control Challenges
Extensive corn lodging caused by high winds and thunderstorms leave behind a weed problem that may take some growers by surprise--volunteer corn. Ignoring this weed is costly, particularly when soybeans are planted. Volunteer corn is very competitive, stealing moisture, fertility, sunlight and yield from both soybeans and corn. Even worse, volunteer corn left in the field past silking can encourage western corn rootworm and gray leaf spot disease to invade a subsequent corn crop.
Research by South Dakota State University, the University of Minnesota and the University of Nebraska-Lincoln (UNL) show volunteer corn ranging from 800 to 13,000 plants per acre can steal up to 54% soybean yield and 13% corn yield. Clumps of volunteer corn from dropped ears are more competitive. UNL research found 3,500 corn clumps per acre reduced soybean yields by 40%, while the same population of single plants cut yields by 10%.