What’s in a Silo?


Farm Notes

Our 3 silos: One Harvestore; 2 concrete stave

I pause to shake my hands and get the blood flowing again. My palms are sweaty and my legs feel a little rubbery. On top of that, my heart is pounding because I climbed the first 40 feet of our Harvestore fairly quickly—and maybe a little too confidently. I still had 20 more feet to climb! As I pause to catch my breath and look down, I foolishly let myself think of what would happen if I misjudged reaching for the next rung on the ladder. “You’re not afraid of heights,” I remind myself, “you’re just out of shape!”

Perhaps you’ve had this same experience climbing a 60’, 80’ or even 100’ silo. But unless you’ve spent some time on a farm, you may not know much about these strange structures. Sure, everyone’s pretty familiar with the image—the tall, cylindrical building is a pretty classic piece of the iconic farm setting. But what are they for?

The concept of the silo as a place to store bulk materials dates back to the 8th century BC. On the farm, silos hold grains or fermented feeds.  There are actually three main types of silos used in modern agriculture. First and most recognizable is the classic tower made of steel, concrete, or even wood. We have three of this type on our farm, one blue Harvestore and two concrete stave silos.

Second is the bunker or “bunk” silo, a wide trench or bay with three (usually) concrete walls. The farmer fills the bunk with fresh forage and packs it down with tractors or skid steers and then covers it with plastic, oftentimes weighing the plastic down with old tires. If you’ve seen this and wondered what the farmer was doing with all those used tires, now you know!

The last type is a bag silo, which is a large, long plastic bag that accomplishes the same thing its vertical cousin the tower silo does—except horizontally. This type is a relatively new and inexpensive option.

Like so many things on the farm, silos have the potential to be quite dangerous. This is especially true during filling, emptying and repair or demolition. Filling a tower silo requires a PTO-driven loader or blower to carry the harvested crop from the ground level to the very stop of the structure. Any time there is a tremendous amount of activity—large trucks filled with grain or fresh forage coming and going plus whirring drive shafts—there is ample opportunity for an accident. Filling a bunk silo, too, can be dangerous. With each new load, the farmer must pack it down by driving over it with heavy machinery. The loose material can give way or simply be uneven enough for the machinery to roll, taking the farmer along for a potentially deadly ride.

To feed their animals from a tower-type silo, farmers originally had to climb to the top of the silo with a pitchfork and toss the feed down. Later, machines were introduced that would “ride” on top of the feed, blowing it down to a feed cart below. The big blue Harvestor’s unloader is a powerful motor-driven chain that sweeps feed from the bottom of the silo. Of course, chains and motors can break and things can get gummed up. Our own Harvestor’s metal floor had once pulled up after getting caught on the sweeper arm. Fixing it meant someone had to crawl into a 3-foot high cave-like gap under hundreds of tons of feed to make the repair before it would work again. I literally could not watch. In fact, I might have hidden in the house until it was all over.

Older tower silos, especially the ones made of concrete, can become unstable over time or are simply in the way of an expansion. In order to take one down, the farmer will first cut away the steel hoops keeping tension on the lower level. He will then hit the side of the silo with a sledgehammer, slowly breaking out a large section near the base on one side (the side where he wants the silo to fall). There are plenty of videos of this procedure online and I highly recommend watching one or two. But hold onto your stomach, it is extremely dangerous and hard to watch!

A Different Type of Silo
Well before I knew anything about silos in agriculture, I understood a very different definition of the word from my experience in the corporate world. Silo mentality or “silo thinking” is a term used to describe people in an organization or business that are strictly divided along department lines. People in these types of organizations are insulated and isolated from one another. They may be very good and focused on what they do within their department, but are incapable of looking outward and seeing themselves as a part of a much larger entity. The result is an “us-versus-them” mentality that has the potential to hold the business back in a variety of ways. The best, most nimble and forward-thinking organizations work very hard to ensure that “silo thinking” never takes root.

I found myself doing my own bit of silo thinking a few years ago. As part of our local food movement, I have made many friends with the same passion of helping local agriculture to thrive. However, it was when the conversations turned to what was wrong with the rest of agriculture that I started to wonder if I was in a silo. When others in the local or organic food movement would use terms like factory or industrial farms, or compared seed improvements to Satan himself, I had to step back and reassess my position on these issues. Who did they mean when they said factory farm? Is it possible they were misinformed about the safety of GMOs? How “big” is “too big”? My list of questions went on and on. I only knew that the conventional farmers I know and love are good stewards of the land and their animals…and did not deserve to have their hard work and experience dismissed out of hand quite so easily. The push-back I heard from “big ag” against farm-to-table type farmers has been equally dismissive and, at times, inaccurate.

Unfortunately, there is a great deal of silo thinking going on in agriculture today—local, organic, conventional—each one fairly isolated from the other. The root causes of this rift are many, but one good example is the documentary “Food, Inc.”, an inspiration to young newcomers to try novel approaches (a genuinely good thing), while causing tremendous dismay amongst other farmers and scientists by sharing a great deal of misinformation (definitely a bad thing.) The resulting “us versus them” mentality could be holding us all back from finding the best answers to feeding a growing planet.

So, how did I get out of that “silo”? I made an effort to talk to all sorts of types of farmers, to read industry publications representing all corners of agriculture, and began following respected science-based organizations like The Genetic Literacy Project. As it turns out, it’s complicated; but I’m now more optimistic than ever about the future of farming. There are challenges, yes, but nothing thoughtful planning and cooperation can’t overcome.

In other words, silos are great for storing feed… but that’s about it!