Heather Ainsley
ECB Publishing, Inc.
The world is full of myths and superstition, and these fantastical tales teach us little lessons about life and encourage us to keep out of trouble. If you swim right after you eat, you'll drown. If you swallow your gum, it'll be in your stomach for seven years. If you have wet hair and go outside in winter, you'll catch a cold. Farming life can have its own superstitions. If your chickens tuck their heads under their wing while your pigs tussle in their pen, it means it's going to rain. Carrying an acorn while working on your tractor can bring you good health and will bless your crops. If you bale hay while it's wet, it will catch fire and burn the barn down. But... while it may seem like a load of tall tales, that last one is actually true, and I've seen it with my own eyes.
Several weeks ago, I was pet sitting for a farm. They have small cows, several horses, chickens, dogs and cats. Everything you might expect to find on a farm. As I was leaving one day after the morning feeding, I passed by the cow pen in my car and glanced over. I noticed a cloud of dust coming up from the field, and thought to myself, 'aww, cute, the cows are taking a dirt bath.' I do so love when big farm animals roll around happily in the dirt. It was then that a thought struck me.
There was no dirt over in that part of the field. It was the end of May and we had had a steady supply of rain all week – that field was mud! I had had to trudge through that mud to get to the barn to feed the animals. So if the dirt wasn't dusty, what was all that dust from? Was it pollen? I looked around at the many trees. Possible, but pollen clouds move downward from the trees, not upward towards them. Could it be smoke? There should be nothing in that field that would be smoking. Curious and a little concerned, I got out of my car, and went out into the field to investigate.
What I discovered was the remnants of an old hay roll that was piled on a couple of fallen tree limbs. It was clearly a “discard” pile; the cows had a fresh hay roll by their trough. It wasn't a big pile of hay, it came only about to my thigh at the highest point, but sure enough, the strange cloud was coming from this hay, which was damp and covered in cow patties, as the cows had trodden around and through it.
Confused, I wondered if the cloud was steam. After all, it was a hot day, and the pile was undeniably soaked through. I'd seen steam coming off asphalt roads after a good rain on a hot day before. But as I pulled the wet, matted clumps of hay back, I heard the undeniable sounds of embers crackling. It seemed unlikely that a pile of hay that was so sopping wet could possibly be on fire, yet there it was, under the top layers of soggy hay: hot embers and white ash surrounded by wet mats of poop-covered hay. But how could this be?
So I did a little digging, and learned that it is extremely common for hay to spontaneously combust, especially if it is wet. There have been numerous reports of barns and farming facilities catching fire due to the combustion of wet hay. In fact, according to an agronomy specialist in Oklahoma, “wet hay is more likely to spontaneously catch fire than dry hay. Excessive moisture is the most common cause of fire in hay bales and stacks.”
The reason for this is simple. Wet hay will rot. As this rotting hay breaks down, fungi and bacteria take over, doing what they do best in decomposing the plant matter. This process gives off heat. Hay is a great insulator, and those tightly-packed rolls or layers in the hay bale prevent any heat from escaping. So as the bacteria keeps digesting, the heat builds and builds within the hay layers, and this can produce some seriously intense temperatures.
Because hay comes in such finely woven layers, even if a bale or roll of hay gets wet partially, there will be dry sections within the roll. As the temperatures steadily increase, those dry sections can start to smolder, but due to the tight environment, there may not be enough oxygen for full, open flames. This causes your hay to look perfectly ordinary from the outside, while the inside is a ball of burning embers. The best indication of a hay bale that has overheated to the point of combustion is smoke.
Individuals who bale hay should only bale when the hay has had sufficient time to dry. Heating can occur in any type of baled hay if the forage moisture content is 15 percent or higher. According to experts, depending on the moisture content at the time of baling, how the hay is stored, it could be at risk for not just overheating but also molding. It takes anywhere from a few days to 10 weeks for the heat to build to the point of combustion, depending on conditions.
Those who have hay stored should check their hay regularly. If they notice a distinct, musty odor, there is a chance that the hay is beginning to heat up. If it is suspected that the hay is heating up, insert a probe or thermometer deep into the hay stack. A probe can be made with a long pipe or electrical tubing, with the thermometer inserted into the hollow center. Check in several different places within the hay bale, and leave the thermometer in place for long enough to get a good reading.
Hay temperatures above 175 degrees means the risk of fire is imminent.
If you notice smoke coming from your hay bale, it is crucial that you DO NOT break open the bale or roll to look inside. This can let in a rush of oxygen and allow the embers within to explode with flames that will be uncontrollable. If you suspect your hay is on fire, call the fire department. Even if you don't think it's necessary, alert them to the potential issue. It takes less than 30 seconds for a single, small flame to turn into a blaze that is out of control.
Although the risks of property damag and animal harm are significant when considering a hay fire, flames are not the only concern when it comes to burning hay. Some hay is treated with preservatives before baling. These preservatives can contain chemicals called ethoxyquin and butylated hydroxytoluene. While that all sounds like a bunch of mumbo-jumbo to those of us without chemistry degrees, those chemicals can release hydrogen cyanine gas (which is deadly) when they reach 240 degrees (F) or higher.
If you notice a small pile of soggy hay (emphasis on small) that has begun to heat up, like the one at the farm I was tending to back in May, extinguishing any hot spots can help control the issue. Note: this should only be done if all of the hay is already soaked through and open to the air. Never separate a pile of smoldering hay that is dry, and always call the fire department to have them on standby if needed.
The hay will need to be spread out, with all clumps removed, and doused completely to ensure the fire is completely out. After a fire is extinguished, it's a good idea to take any remaining clumps of hay and haul them away to be discarded safely. Keep a watchful eye over the next several days/weeks to ensure that no flare ups take place.
We hear superstitions and old wives’ tales all the time. It can be very easy to simply dismiss advice if it seems farfetched, but there could be a little truth mixed into the tall tales. It can never hurt to do a little research, and when in doubt, maybe don't swallow your gum.