Those Big Tall Blue Things

I thought I’d write about “them there big blue tubes” we have on the farm. They are silos, or to be proper Harvestores. People ask what we have inside of them and I tell them missiles. We are a part of a secret self-defense network with the government and if anything happens we are ready. The tops pop off and missiles will shoot out to protect us. Come to think of it a Farmer could probably do just as good a job as some of our government officials. I deviate, let’s get back on track.

In simple to understand terms, silos are basically feed containers. They hold and preserve the feed we grow for our cattle. They are glass lined, steel structures. We have 14 on the farm and we store high moisture corn, corn silage and alfalfa haylage.

While it would take pages to fully explain the concept of the Harvestore system, I will give you a scaled down, easy to understand, non-text book version.

A firm foundation is most important when beginning to build a Harvestore silo. Our tallest at 110 feet required a large circular hole to be excavated and filled with yards of concrete. The top of this concrete becomes the floor of the Harvestore. This floor is then covered with a thin layer of epoxy to protect the concrete from the acids and juices formed when the crops inside the structure go through the fermentation process.

The silo is built from the top down. The first sets of sheets are built with a hoist contraption inside. Each ring is formed by bolting curved pieces of glass lined steel into a ring. After the first ring is complete, the roof is built on top of the first ring. Once that is done, the whole first ring and top is hoisted up and the second row of metal sheets are added under the first row and bolted until the second row is complete. Then those two rows are hoisted up and the third row is added below the top two and so on and so on. It’s like a reverse of stacking blocks. You are lifting up what you had in place and inserting more underneath to build up to the height of the silo. As succeeding rings of sheets are added they become increasingly thicker to be able to support the weight of everything above.

When we enlarged our farm a few years ago, we added two more 25 X 110 structures. That means they are 25 feet in diameter and 110 feet high. The weight of one is 74,000 pounds, has 22 rings, 198 sheets and 17,000 bolts. A seven man crew did the job.

Once the structure is up, they close the hatches, fill it with pressurized air and check for air leaks by hanging in a chair contraption and swing around the outside of the silo making sure that each bolt and each sheet is sealed. At the place where the sheets come together there is a sealer applied to make it airtight. Around and around and down they swing. An agricultural trapeze artist.

The idea behind the Harvestore is to store and preserve the feed in an airtight container and preserving the feed for optimum quality. The feed is blown up a pipe on the outside of the silo and into the top, filling it all the way. Once it is filled an airbag is lowered and the top door is closed. The bag “breathes” and keeps the feed airtight. There is so much more to explaining the air bag. That will be saved for another time.

To get feed out of the silos there is an unloader in the bottom which is put in before the silo is filled. The unloader looks like Paul Bunyan’s chain saw. It is a metal arm half as long as the silo is wide with a chain loaded with metal teeth. The chain goes around while the arm slowly rotates inside the silo. The teeth pull the feed out of the unloader’s door and onto a conveyor belt. This contraption is dangerous. Farmer’s father had a bad accident and almost lost his arm in the process. Even when it is pulled out of the silo to fix something it is hazardous with all the sharp teeth.

Once a week a feed sample is taken to test for the quality of the feed and the nutritionist gives us a “recipe” to add to the feed for our TMR – Total Mixed Rations. Each group of cows is fed their own mix and it is always changing.