URBANA In what amounted to a kind of census of sweet corn grown for processing, three years of data from 175 fields in Illinois, Wisconsin, and Minnesota shed light on what works and what doesn't. Along with identifying the most troublesome weeds, the results also revealed some of the more complicated relationships among factors influencing both weed control and sweet corn yield in the Midwest.
"Rather than a typical controlled field experiment, this was a large scale approach. We wanted to find out what some of the driving characteristics are on the regional level for sweet corn production," said University of Illinois and USDA Agricultural Research Service ecologist Marty Williams. "We contacted sweet corn processors in the Midwest. They supplied us with fields to study as well as a huge amount of information on the agronomic practices used in those fields, such as planting dates, tillage practices, and herbicide use."
From other sources Williams acquired environmental data for the fields, including temperature, rainfall, and latitude. In all, the study analyzed 20 environmental variables, 30 agronomic variables, and 56 weed species.
Identifying which weeds were most abundant was the easy part.
Just prior to harvest, Williams and his team walked the 175 fields and noted the weeds present. "Most of the fields had a number of species," Williams said. "On average, there were four to eight weed species in a field. Most the fields were dominated by a couple of species, but it wasn't the same dominant species from field to field."
The most abundant weed species they observed in the Midwest were fall panicum, giant foxtail, wild-proso millet, common lambsquarters, and velvetleaf. Williams added that each state had its own uniquely dominant weeds.
The next step, finding characteristics of the best and worst fields, was much more complicated. Williams was looking at not only sweet corn yield of the 175 fields
|Contact: Debra Levey Larson|
University of Illinois at Urbana-Champaign