After the harvest comes the bounty. I’m not sure who said that line or if I just made it up, but I like this statement. Many of you have completed the arduous tasks of preparing, planting, spraying, and fertilizing summer crops. Corn, milo, soybeans, and sunflowers have been or are very near harvesting. To livestock producers now is the time to reap the bounty.
One of the great assets a bovine possesses is a four chambered stomach. The rumen, reticulum, omasum, and abomasum are individual chambers in the ruminant stomach and all have key roles that make cattle some of nature’s greatest foragers. Ruminants specialize in consuming plant based fibrous materials that you and I can not digest. Approximately 36 percent of the USA surface area is rangeland unsuitable for farming. Worldwide 40 percent of land mass is rangelands. These statistics are why animal agriculture is critical to feeding the seven billion people worldwide.
Corn and milo stalks are terrific feedstuffs for cattle. Some refer to them as crop residue, fodder, or stover. To each their own. When the combine header comes through the field it usually does not touch the ground. The remaining stalk is available to livestock allowed to graze the field afterwards. Some milo heads, corn kernels, and corn cobs may have also survived the harvest. Cattle have shown they will consume these feedstuffs. They prefer grain over leaves, leaves over stalks, and stalks over cobs. I can’t say I blame them. High nitrate and prussic acid levels can be a problem in corn and milo stalks. Before you graze, I recommend taking a forage sample and have both levels measured before you turn out. Also, filling cattle up on hay prior to turn-out will reduce the risk of nitrate and prussic acid poisoning.
When given a large field, say 60 acres, to forage cattle will “cherry pick” it for grain first and foremost. Too much grain ingested too fast leads to acidosis, or an over acidity within the rumen. Effectively, the pH drops so low rumen lining is burned and that ruminant becomes a temporary monogastric or dies. Tragic, but true. Damaged rumens can take up to four months to recover. Corn fields are much more likely to trigger acidosis than milo fields. Cattle simply can pick up corn seeds more easily than milo seeds.
The best way to treat acidosis is to prevent it all together. Instead of giving cattle an entire field of stalks, only grant them access to a small portion. This increase in stock density forces cattle to be less picky and eat the stalks, cobs, leaves, and grain as available. Rumens are safe as the more fibrous materials digest slowly to compensate for the grain’s rapid digestion. Dividing a field with hotwire is an excellent method to limit graze cattle on stalks. Move one wire each day while allowing access to graze the previous days stubble. This limits extra hot wire construction and supply.
Dry cows grazing stalks is a great time for supplemental feeding. This may seem counter-intuitive as cows are quite possibly foraging grain from these fields. Nutritionally, this open second trimester cow requires less nutrients than any other time in her life. Weaning calves cuts cow nutrient needs by almost half. On stalks cows will consume right at 1.5 percent of their body weight a day. That is 18.75 pounds of forages for a 1,250 pound cow. Nothing to write home about. With just stalks cows could lose over two-thirds a pound each day. Studies have proven supplementing with high protein feedstuffs, even at small amounts, can increase forage digestibility and cow consumption thus adding cow body condition. Condition that can enhance colostrum production and reduce spring supplementation demands.
High protein feeds that come to mind are dried distiller grains, soybean meal, premade 32 percent crude protein cow cubes, canola meal, and corn gluten. Always ask for a feed test to know what you purchase and feed. Compare feeds on a dollar per pound of protein basis.
Rules of Thumb
• 1 acre of stalks = 1 month of grazing per cow
• Test stalks for nitrates and prussic acid prior to grazing
• Each bushel of corn yields about 16 pounds of forage per acre
• Provide mineral and salt free choice to cattle
After the harvest share the bounty of stalks with cows. They will thank you.

Alicia Boor is the Agriculture and Natural Resources agent for Barton County K-state Research and Extension. Contact her by email at aboor@ksu.edu or call 620-793-1910.