Maximize Energy Production From Grain Crops

Three ways to boost potential energy harvested from corn acres this fall and winter.

Published on: Aug 21, 2012

Livestock producers face record high prices for corn and energy in dairy or beef rations. Some are already heading to the fields with their silage choppers.

But stop at least long enough consider these three ways to maximize harvested corn energy from Greg Roth, Extension agronomist at Penn State. It may change your strategy for better results, he hints.

Consider delaying silage harvest a few days
Penn State and University of Wisconsin colleagues collaborated in a study over six locations, measuring starch in silage at 25% milkline, half milkline and 75% milkline. Then they compared that to the corn yield harvested by combine.

HOLD OFF SILAGE HARVEST? Corn is laying down 4 to 5 bushels of grain energy per bushel per day. Thats energy needed in feed rations.
HOLD OFF SILAGE HARVEST? Corn is laying down 4 to 5 bushels of grain energy per bushel per day. That's energy needed in feed rations.

"We converted the starch yield to bushels, assuming corn grain is about 70% starch," explains Roth. "Grain yields increased by an average of 61 bushels per acre between early silage harvest and the combine yield. Between the half milk and combine harvest, the increase was 37 bushels per acre.

"While these numbers sound high, consider that a high-yielding corn crop is laying down about 4 to 5 bushels per acre per day during grain-fill. So, a five day delay in silage harvest could likely mean an extra 20 to 25 bushels of grain energy per acre in the silo.

"Delaying harvest can lead to more issues in getting a good fermentation. So, carefully consider how long you can delay harvest for your particular silage storage structures. At least think about it."

Roth also cautions that this year's silage is maturing earlier than normal. So base your decisions on the crop maturity not the calendar.

Harvest high-moisture ear corn as snaplage
Snaplage harvest generally results in 10 to 15% more total digestible nutrients than shelled corn, and has an earlier harvest. Harvest costs will generally be lower with a forage harvester than combine.

There are some management issues with snaplage, he concedes. But they seem to be less than were encountered with high-moisture ear corn harvested in the past.

For a good summary of the pros and cons of snaplage, review a factsheet from the University of Vermont and this presentation at the 2011 Penn State Dairy Nutrition Conference.

This might be a good year for snaplage since our corn silage crops will likely be short and low in fiber, suggests the agronomist. Having another energy source that has more fiber in it will be valuable.

The earlier harvest (black layer or 34-36% grain moisture) allows more potential for winter forage crops following corn for grain. Also, the cost of purchasing fiber is high this year as well, so it pays to use more of that produced on farm.

Follow early harvest with small grain silage
A small grain silage crop planted immediately after early corn harvest could provide high energy feedstuffs. One of the best in this regard is barley, harvested at the soft-dough stage.

"This is a practice done by some Lancaster County (Pennsylvania) producers who direct-cut in the narrow window when whole plant barley is in that soft dough or 35% dry matter stage, often in mid to late May," explains Roth. "Then they double-crop with corn."

This provides a supplemental silage crop for use during summer that's nearly equal to corn silage. It provides a winter cover crop, a place to spread manure in late spring and a way to spread out planting and harvesting. It also helps to reduce drought risk, since barley is fairly drought tolerant.

All of these strategies require some additional management and consultation with the nutritionist, he cautions. But they appear to have some potential for increasing energy production per acre and ultimately reducing feed costs. And that's hugely critical.