CORN SILAGE 2014: A DIFFICULT DECISION
For years we have had sufficient supply of corn silage and BMR corn silage to feed fully fermented silage through the Christmas holidays and beyond. In 2013, however, we fed ourselves out of corn silage. Now we need to make up inventory.
As you may recall from previous Farm Report articles, we ran out of conventional corn silage last August and out of BMR corn silage in September. We had to purchase CS for a month and changed diets to increase the amount of haylage in the ration. We lost some milk but survived. Now we are left with the task of replenishing our inventory.
Crop year 2013 didn’t help much, with yields of about 17T/A of both conventional and BMR CS. This isn’t enough of either to maintain our typical nutritional strategy of 55-60% forage, or 20-24 lbs. of DM from conventional and BMR CS. The quality of 2013 CS was not great either. We chopped a fair amount of weedy, 28% starch corn. The wet spring and early summer resulted in poor weed control, and a dry July-August affected pollination and ear development. With a limited supply of good quality haylage, you can only do so much with “heifer haylage”, grain and NFFS to make milk.
We are feeding our high quality forage and BMR CS only to the fresh and high cows. Feeding just over 6 tons of BMR/day, with 1100T in inventory as of March 3, takes us through August. Feeding about 7 tons of conventional corn/day may get us into October. Clearly we will not have much if any carryover to feed well-fermented CS through 2014. Not a desirable situation for any farm, but for running feeding trials this becomes very difficult. Having stable and consistent forage quality is critical for the research ration, where the nutritional quality of the diet needs to be held constant. Varying starch digestibility as silage cures, especially in its first 3 months of fermentation, can greatly affect a feeding trial. This severely limits our ability to run cow trials in the fall. We need to have sufficient supply of fully fermented CS to run these trials. The issue becomes how best to rebuild that inventory.
To harvest a 455 day supply of corn silage (365 days + 3 months) to be fed at a rate of 12 tons/day, accounting for 20% shrink from field to cow, on 350 acres we need yields of about 19 T/A. This is attainable for us.
What this means is that we need to focus on a single type of corn silage, either all conventional or all BMR. Part of our problem of running out was bunk face management in feeding both conventional and BMR CS year-round; at times requiring us to feed more BMR than necessary in order to avoid spoilage. Also, since BMR has higher NDF digestibility, cows consume more of it, coupled with some yield drag and vulnerability to poor weather in our experience; we would need to plant about 20-25% more acres of BMR than conventional CS. This just is not feasible. Therefore, we have decided the best way to rebuild inventory on the limited acres we have available for corn is to not plant BMR CS this year and to plant only conventional CS. We have selected a few varieties focusing on higher yield and milk/acre in the 2013 Cornell corn silage variety trials. As we have stated before, the higher the NDF digestibility, the more they eat and the more you need to grow and harvest maintain or rebuild our inventory. We got caught.
Really hoping for a decent crop year.
— Kurt Cotanch