Are You Dense?

My brother used to say that to me a lot. It was usually – well, no – always – after his little sister had done or said something really dumb. “No, I’m NOT!” I would retort, and stomp away.

For our purposes here, I will rephrase that question and give a totally different meaning: Are your silage piles dense?

Density is one of the BIG keys to a successful forage pile. We encourage a packing density of 15 to 16 pounds of dry matter (DM) per cubic foot.

Referring to an article written by Dr. Keith Bolsen for Progressive Forage Grower, “Packing density: Putting dollars to densities” he tells about working with a family whose drive over pile of corn silage had an actual 11.4 pounds of DM per cubic foot, determined by a core-sample testing method. The silage was unstable at feed out and there was visible surface spoilage. The shrink loss estimated by Dr. Bolsen was 20 to 25 percent. This was a smaller dairy, and it was a few years ago, but the relative numbers don’t change.

Dr. Bolsen and the owners sat down with their team – including the silage contractor, the nutritionist, the feed company representative, and the banker. Density was determined to be the number one problem at 11.3 pounds DM per cubic foot – close to the actual 11.4 pounds. Using that same spread sheet, they plugged the number in to see what would have to be done to get to a density of 15 pounds.

Here is what they did:

  • Forage delivery rate increased from 75 to 90 tons per hour. The silage contractor had a higher capacity forage harvester, which had a kernel processor on it.

  • Average whole plant DM increased from 32 to 34 percent.

  • A 35,000 pound second pack tractor was added to the pile and 5,000 pounds was added to the first blade/pack tractor.

Here is what happened:

  • The predicted density was 16 pounds DM per cubic foot. Actual: 16.4.

  • As silage density increases, shrink decreases. Increasing density from 11.4 to 16.4 decreased the shrink loss by 5 to 7 percent from the first year to the second.

Bottom line:

  • There were 3,500 tons of corn silage in the pile with a value of $60 per ton.

  • Reducing the shrink loss from 20 percent to 14 percent saved 210 tons of silage – or $12,600. The cost of adding the second pack tractor was $5,250 ($1.50 per ton).Current estimates on cost of adding a pack tractor are between 75 cents and $1.50 per ton, depending on cost of fuel, weight of the tractor, and other discretionary factors.

  • Net saving: $7,350. Remember, this was a smaller dairy – think of the relative cost savings you could realize.

Please follow this link to the full article – there you will also find “Twelve key considerations to improve density”. Dr. Bolsen gives explicit instructions that should be followed by pack tractor drivers.

We appreciate Progressive Forage Grower giving us permission to cite and reprint this article on our resources page.

So – are your silage piles dense? “Why, yes, they ARE!” is the correct answer!

There is a way to do this at your farm.

Talk to your nutritionist or advisor. Call us at 559-779-5961 for help.