“The old timers will tell you that drought years scare you to death and wet years starve you to death,” says feed consultant Don Sanders.
Talking with a group of farmers in Waunakee last week about how to deal with drought-stressed feedstuffs for their dairy and beef cattle, Sanders said that old saying is true because feed raised in a drought year will still perform in livestock while the feed from wet years just doesn’t perform.
The comments from the old-timers are particularly sought after this year. One 90-year-old farmer told Sanders that he sold a cull cow in 1936 — also a particularly bad drought year — for $18 and bought a ton of hay for $20.
Others are saying that in 1936 farmers cut down box elder trees so the cows could eat the leaves.
Beyond cutting down trees, Sanders sees some opportunities for livestock operators in the current drought if they pay attention to feed values, the proper time to harvest and ensile drought-stressed feeds, take into consideration nitrates in the corn plants and look at alternative feeds.
Farmers should pay attention to high nitrates in any corn they chop for silage because the plant took the nitrogen up from the soil but could not turn it into corn kernels or cobs in many cases.
That means that nitrates are concentrated in the stalk of the plant, especially the lower foot, and can lead to more silo gas than usual.
Sanders cautioned farmers to take extra care if they put drought-stressed corn into an upright silo especially if it is attached to a barn where cows are housed.
“Cows will die from silo gas,” he said.
Even farmers who store their silage in bunkers or horizontal bags should take extra care in watching for silo gas this year. Farmers have been known to be overcome by silo gas near the open end of a bunker silo, he said.
The nitrates and thus the silo gas given off by the corn will be worst right after harvest. He advised farmers using upright silos to finish up with the silage right away — covering it or dropping the unloader and then staying away from it.
The fermentation process of ensiling will help take care of some of the nitrates in corn silage and the content of nitrates going into the silo can be mitigated by cutting the corn a foot off the ground, which will eliminate the part of the plant that has the highest levels.
HIGH NITRATE DANGER
In the rumen of cattle, high-nitrate feed will break down to nitrites, which become ammonia and pass into the blood. A level high enough can kill a cow.
In the ration, a nitrate level of 200 parts per million (ppm) is okay but once that level rises to 1,000 ppm changes start to happen in the cow “that are not good — that’s when the blood starts to lose its oxygen-carrying capacity,” Sanders said.
When oxygen doesn’t get to the cells a cascade of problems will occur.
Sanders further cautioned farmers to remember not to dry and bale high-nitrate corn for use as bedding because if it’s in the vicinity of cows they may eat it and still suffer the consequences.
Some people have round-baled drought-stressed corn and covered it with plastic, but Sanders said he’s not a fan of that practice. Corn stalks can poke through the plastic, letting in air and derailing the ensiling process. Also, the practice brings in a lot of “ash” or soil, which is an enemy of good ensiling.
The soil includes clostridium bacteria, which can outnumber the bacteria that are beneficial for the proper ensiling of feed, he added.
Sanders said farmers need to plan their feed inventory carefully this year and make plans based on how many animals they will be feeding and how much crop they will likely be able to harvest — from their own fields or from the fields of neighbors.
Sanders and colleague Justin Munson, who both work for Agri-King, gave farmers some guidelines for using drought-stressed corn for silage. If a stand of corn is five feet tall and the bottom foot is left behind, that makes it four-foot corn and it could be calculated at about 4 tons of wet silage per acre.
Even barren corn stalks can make pretty decent feed, they said, although the nitrate content will be the limiting factor.
“Any time there’s adversity there’s opportunity,” Sanders said. “If you can strike a deal with your neighbor you can get some pretty good feed. Everybody’s got to work together.”
Cows or steers don’t have a starch requirement, they have a carbohydrate requirement, Sanders said. “The energy will come from the sugar in the stalks because we didn’t make an ear.” Without the ear, corn is a tropical grass.
Barren corn — meaning it is without any ears — should probably be chopped at one-half inch rather than three-quarter inch and doesn’t really need to be run through a kernel processor.
Munson said that the corn silage “doesn’t have the mortar for the bricks” and farmers need to think about how this chopped corn will perform in the silo bag or in a bunker. He knows a heifer grower who filled one bunker with this kind of cast-off barren corn and it took 340 more acres than normal to fill it, he said.
Some farmers have bought standing corn that isn’t going to produce grain for $25 a ton, but Sanders said farmers need to keep in mind that it’s going to take $20 to get the material to their farms and it will yield 20 percent less material than it would in a normal year.
The consultants recommended sampling the feed when it’s green and going into the silo and then sampling it again when fermentation is done.
They both said that farmers should consider using more inoculant on their corn silage and should not add any urea to their ration or their process because of the potential for nitrate toxicity in the resulting feed.
Sanders said inoculants with Lactobacillus buchnerii should be avoided this year because the goal of the fermentation process should be to stabilize the pH or acidity level as soon as possible. The inoculants that have buchnerii in them would extend the fermentation process.
“With short feed inventories we don’t want to extend fermentation, although we still want the corn to ferment one month or more,” Sanders said.
He also suggested that farmers who have open fields from which they have harvested wheat or other crops consider planting oats at the rate of 3-4 bushels per acre in August.
It must be compatible with any herbicides that were used on the field this season of course, but such a planting of bin-run oats could yield 2-3 tons per acre of feed that could be ensiled to feed cattle.
“In 1988, when I was in Pennsylvania we did that a lot because we needed the feed,” Sanders said.
Munson said he knows farmers who are talking to every neighbor who grew wheat and asking about growing oats on those fields. A variety called “forage plus” oats has the highest digestibility of the oats that are on the market, Sanders said.
Munson said that many farmers are planning for next year by putting winter barley or winter rye in their rotation this fall. That will produce an early forage crop in the spring to help them get their cattle through a short feed situation.
As for other alternative feeds, some farmers in the southern part of the state are bringing in citrus pulp from the South and barley or oats from Canada are another option for putting energy in the ration, Munson said.
With corn trading as high as it is, several corn ethanol plants have already closed, he added and that could change the dynamics of the market.
They reminded farmers that in 1988, the last really bad widespread drought year, the highest prices for corn were in July and they dropped from there.
In addition, with any luck, it could be possible for farmers to see their wet tons of corn for silage double if rain comes every week, Sanders said.