How to barn-dry square bales to make high-quality hay
Interview with Sam Zook, President of Keystone Bio-Ag
Acres U.S.A.: For this method, are you barn-drying loose hay or do you bale it first?
Zook: We do everything in small square bales. We bale it out in the field and then bring it into the barn to dry. People want clean, dry hay for horses without mold.
We’re in southeastern Pennsylvania and have high humidity. We’ll usually have one of our cuttings dry in the field, but it normally takes three and a half days — almost four days — to get good, dry horse hay. Sometimes dairy farmers will use less than completely dry hay, but it’s just not worth the risk for horses.
With this method, two nice days is all we need. We cut it before noon, or at least around one or two o’clock, and we bale it the next evening. We’ll often ted it once or twice in the meantime. But don’t ask me what the moisture content is when we bale it, because I don’t know. It’s kind of an art.
By that evening of the second day it’s still nice and green. It’ll keep its color after the drying — it’s usually about as green after drying as before. Without the fan drying it would get mowburnt. It would ferment a little bit. It just gets brown.
I really like this method because it can make hay dependably. If it’s predicted to be nice weather, you cut it one day and put it in the barn the next. It’s not that hard to get hay almost finished by drying it out in the field like normal; it’s that final touch that’s very challenging. We just do that in the barn with the fan.
Acres U.S.A.: So what does that look like in the barn? How are the square bales arranged and where does the fan go?
Zook: We have a typical post-and-beam barn with 16 feet between the posts, and it’s about 45 feet long. So we build a mow that’s about 16 feet wide by 45 feet long. We set the fan at the front of the barn and we drive in the back.
The fan is in a box. It’s a 4-foot fan. We built a plywood box that we can stack the hay around.
I talked with an old-timer about this before I started. They actually did this back in the ’40s. It was a very common practice in this area.
The key is to stack the hay so as to leave a tunnel down the middle of the mow — about 2 feet wide and as high as the fan is — 4 feet — to blow the air down. We stack the hay equally on either side of the tunnel and on top and on both ends. We stack it fairly tight, so there’s no easy out for the air; it has to push out through all the hay. We made a 2×4 frame to put on the top of the tunnel for support so the bales don’t fall down into the tunnel.
So if you were inside this 2-foot by 4-foot tunnel, there’d be about 7 feet of hay stacked above you and to your left and right. The fan is behind you, and ahead of you, at the end of the barn, is another wall of 7 feet of hay.
The reason for the box for the fan is so that we can stack seven bales above it, and so we can stack hay tight up against the box as well.
We’ve done as many 900 bales in one mow. The number of bales isn’t as important — we’ve done as few as 350. We just brought the sides in a little bit, but we use the same principle.
Acres U.S.A.: What horsepower is the fan?
Zook: It’s a 4-horsepower motor and pulls 18 amps — single phase 220 volt. It takes some power, but it’s not going to be too bad for your power bill. It creates a lot of static pressure.
Acres U.S.A.: How many days is the fan blowing?
Zook: It depends a little bit on how wet the hay is. The very first batch I made I thought this method was going to dry really wet hay. The bales I made were so heavy I could hardly pick them up — they must have weighed 120 pounds. I ended up throwing those out — they didn’t dry.
I usually figure a minimum of four or five days running 24/7. Then, to finish it off, I shut the fan off overnight and run it another couple of days during the afternoon for four or five hours. It won’t heat anymore at that stage, and the afternoons are when there’s the least amount of moisture in the outside air.
It depends a little bit on the humidity. With fairly dry weather it won’t take quite as long.
Ideally, I’d put a little bit of heat to it. I could cut the run time in half. I experimented with loose hay and blowing heated air. In two or three days it was done.
Acres U.S.A.: But baling it in the field makes it a lot easier logistically than using loose hay.
Zook: It does.
Acres U.S.A.: Is the end product uniform? Are the bales from the outside edges of the mow as dry as the ones nearest the fan?
Zook: The ones on the inside tend to be a little drier than the ones on the way outside corners. But I’ve found that if I make my mow square it helps.
Acres U.S.A.: And after this is all done, it’s essentially top-quality horse hay.
Zook: Pretty much. It’ll be top price at auction every single day. And you don’t lose a cutting to rain as easily.
Acres U.S.A.: Do you notice a difference in quality from first cutting to second to third — the same with this method as for regular hay?
Zook: Not really, no.
