As historic as 2020 has been for life in general, one silver lining is a seemingly adequate growing season for farmers compared to years past, according to Rock River Laboratory. However, a "near-perfect" growing season still comes with necessary tweaks to harvest corn for ideal silage, the company said, noting that the area's weather and environment are just the beginning of a myriad of management considerations harvesters should think about when preparing to chop silage.
John Goeser, Rock River Laboratory animal nutrition, research and development director, said, “It’s interesting: In years where we have adequate feed inventory and above-average yields, we typically have below-average forage quality.”
Heat units and moisture this spring and summer hit “good” on the growing spectrum, but what is great for the plant may actually not be ideal for the feedstuff it becomes, he said.
“Lignification is likely to be greater this year, and I’m hearing about above-average grain yields,” Goeser said. “These observations could boil down to less-than-ideal fiber digestibility.”
Goeser noted that lignin is concentrated at the bottom of the corn plant, and as such, high cutting corn for silage at harvest could help improve the fiber digestibility of whole-plant corn silage that is made.
“High cut means 6-10 in. higher than normal, which can be various heights, depending on the preference,” Goeser said. “This can go up to 2 ft. high, yielding a feed that is similar to almost snaplage or earlage.”
The nutritional components of corn silage are affected by cutting height. Research has found that in high cutting-height harvests, silage quality increased, while dry matter yield decreased, Goeser noted, recommending that harvesters start from the “normal” cutting height of harvests in years past and go up from there.
Scouting fields is still an essential practice during a good growing year. “Walk corn, and look at it from a plant health and condition standpoint,” Goeser advised. If feasible, he also recommended pulling out the chopper a few days early to chop a 100 ft. run into the field at two to three different cutting heights. “Take samples at each cutting height, and send them into the lab for a nutritional measure to dial in your timeline and reap the rewards of expertly timed harvest.
“Consider using the InField updates free tool for dry matter, neutral detergent fiber and starch measures to understand plant maturity as well as moisture in similar regions,” Goeser suggested.
Another option is to cut numerous stalks out of the field at different heights, chop them with a wood chipper or other means and send a sub-sample to the laboratory.
Goeser also encouraged strict attention to both milk line and moisture to time the harvest. “If the milk line advances past maturity, let it go a little further to hit moisture at the right time. Missing moisture and harvesting on the dry side can wreak havoc on the silage quality,” he explained.
In such cases, he recommended shortening the cut length in an effort to save the crop’s potential.
As farmers in Iowa face difficulties associated with the aftermath of the recent derecho storm, they must consider all options available for their corn crops.
“For corn that is snapped off and dead or dying, growers should speak with an agronomist to discuss what they can do at this point,” Goeser said. “Removing the plants from the field is the first priority in this type of situation. If it’s just lodged, corn is incredibly resilient and will likely gooseneck and stay alive.”
In such cases, Goeser recommended networking with local grain farmers to help them in a time of need but also potentially salvaging what could be cheap feed. “If harvesting damaged fields in this region, scout the field prior to chopping — being mindful of remnants from the storm while also ensuring no employees are in the field when chopping has commenced.”