Is wet straw a fire hazard? ...

[Bocktobery 10]

Hi.

I recently acquired several straw bales that I intend to use as bedding for my coop. At the time it was delivered, I was not ready (due to illness and current heat index) to put it in the place where I have it stored for the coop. We ended up putting it in an old barn, the floor of which is dirt and slopes, but there was a rubber tarp on the ground. 10 bales stacked with four on the bottom. Illness and heat advisory continued, so the bales sat in this old barn. I was finally able to get to it today and noticed that two of the four bottom bales had gotten wet and were starting to decompose- just at the very bottom. Obviously I don't want that rotten straw in my coop at all and not even in storage, so I tore out the rotten part in generous amounts so as to salvage what I can from the bales.

Was this ok to do? Or should I have thrown all of the bales that had gotten wet? I looked it up online and found an article about how wet hay bales are a fire hazard. I knew nothing about this. Now I am concerned since I have the bales stacked in my coop- what happens if I missed a wet part somewhere in the straw bale?

Is wet straw bale as hazardous as wet hay bales?

And how common is a fire started from composing (hot) straw/hay bales?

Do I have to worry about this?

Should I pitch the bales I know got wet and just keep the ones that I suspect did not? By the way, the bales got wet because the rain water drained on the floor on the one side of the barn. I would say the bales stacked on top are fine, but how does one really know? I'm concerned I do not know much about this, which is why I need help and asking here. I never really heard of it and need to know more.

Thanks in advance for any replies.

 

[Howard E]

If you had a barn full of wet straw, it might. A few bales, no. Farmers were always concerned about stacking a barn full of hay or straw that had been baled to wet or had been rained on after they were baled. They start to compost and do generate enough heat you can't leave your hand on it. In small amounts, that is a good thing. A sign the composting is really working well. In small amounts, there isn't enough mass to worry about.

Keep and use all of them. They are primo stuff!

 

[Bocktobery 10]

Thanks so much Howard E... and sorry to get back to you so late too. I appreciate your help!

 

[Howard E]

To elaborate, what you were referring to with the bales catching on fire is called spontaneous combustion. There are numerous articles on it......this is a link to the first one I found........

http://ext.wsu.edu/hay-combustion.html

I have heard about this for years......have never seen or heard of a case where it happened.

Generally, it was caused by good quality hay with a lot of moisture in it.....not dried down entirely...i.e, baled when too wet. It does start to compost, then heat up, but generally, they are talking a large mass of hundreds, if not thousands of bales in a single barn. The heat starts, but since it is trapped among all those hundreds of bales, has no where to go so, it keeps building.

One of the problems a lot of people have getting compost going is they do not have a large enough mass of it to trap in the heat to get it going. One of the ways you can tell a compost pile is doing well is it gets so hot you can't put your hand in it. If you want really good compost, that is what you want.

To give you and idea of what to expect, I put 6 hay bales outside on the ground last fall and they immediately got wet, yet nothing happened. It took all winter and some N fertilizer on them to get them to start breaking down. Six months later, they have rotted down, but none of them ever got hot enough to catch fire. I have 10 bales of bone dry grass hay I stacked by my garden about a month ago, and they are outside and getting rained on all the time, and have not caught fire.

I currently have about 50 bales of 3 to 4 year old grass hay in my pole shed.....some of the bottom bales have gotten wet and they are moldy and not fit to feed livestock, which is why I'm using them as garden mulch. They are really good for that. What all of those is grass hay, which is mostly carbon. No legumes, so no Nitrogen. They just sit there.

Last fall I ran 2 or 3 of those hay bales through a chipper shredder and into a 4' diameter compost bin. I even added N. Even exposed to frequent rain, they just sat there. They would dry out too fast and were so light and fluffy they were never able to trap in any heat to get the compost thing going.

Your straw.......I assume it is wheat or oat straw?........may get moldy, but that is nothing compared to what is going to happen to it when you place it in the bottom of a chicken coop. If built up deep, and if it ever gets wet, you may find straw alone tends to mat down, stay wet and start to smell. That means anerobic process from lack of air. If you change it often, it should be OK. If you intend to use it as deep litter, it will work, but will be better if you can mix in a variety of other carbon sources with it.......things like tree leaves, pine straw, wood chips, etc. The birds will supply the Nitrogen and will stir it up...... and combined with the moisture on the floor and oxygen in the air, the material will start to break down into compost over time. But since there is not enough mass to trap in the heat, it is not a hot composting process. So no fire.......but if it started out a foot deep or so, it might warm up some. In my world, that would be a good thing.