Afraid the manure is going to start a fire.

[Ryxie]

So, after learning that piling manure, sawdust, and some hay causes smoldering and could cause a fire, I started finding places to spread out the stuff so it wouldnt be all clustered together. The best place, I found, is my garden. While it probably does good for the plants and trees, it is also nice to walk on when pressed down.

Today, however, I noticed that some old hay had gotten clustered together, and when I pulled it apart there was white in the middle and what appeared to be smoke (maybe hopefully it was just mold?) I immediately poured a couple buckets of cold water over it and spread it out, but I am still paranoid that it is going to catch fire! If I spread it out really well, and make sure there are no clusters of hay, should it be fine? There are a lot of trees in my garden, and I really don’t want to be the cause of the next wildfire in my area this summer!

[Alagirl]

while, yes, manure can catch on fire, no, it isn’t that common.
You are more likely to burn your hay shed down with fermenting bails.

No, small clumps do not get hot enough to catch fire. Those are most likely mold spores yo see. Not something you want to see, but meh, happens.

Aerate your manure pile. In gardeners terms turn it. Best is to do it in a manner where the outside gets shuffled in with the inside to promote even decomposition.
If that is not possible, because of lack of time or volume of manure, you can also put perforated PVC pipes in the pile.

better yet, look into the technology to warm your water with the manure.

You actually want the pile to get good and hot, as that kills off seeds and pathogens and parasites.

[S1969]

My manure pile usually has ash in the middle from the heat; so I would guess that you are also seeing ash - especially if it’s hot. If it’s grey, and hot, yes - ash. Cold and grey, maybe mold.

I agree that manure piles can get hot enough to catch fire, and if your environment is very, very dry - you should be careful. That said, mine has never caught fire, and when I move/flip my piles it is quite hot. But, it really isn’t hot enough to catch fire. Maybe to cook an egg though. I don’t usually see smoke when I flip it but sometimes I do - usually steam though.

If your manure is heavy and wet (e.g. urine soaked sawdust) it will heat up quickly even in fairly small piles. This is a good thing if you are composting - you want it to decompose. But it’s good to be careful. If you are very concerned, make your pile longer and lower; flip it frequently, and/or move it to a safe place.

Might be useful to take the temperature of the pile to see how hot it is getting. I believe they make compost thermometers just for this purpose (in theory, if it’s creating ash it’s too hot for good composting).

[SmartAlex]

Spontaneous combustion? That must be some hot $#!t.
Pile it somewhere away from buildings. Clear any dry or dead plant material away from it. Let it cook itself down. THEN spread it on your garden. Yes it can get really hot, but if you are turning it regularly, you are cooling it and bringing the uncooked material into the center.

We have what we call the “Poop Deck” Surface is concrete pavers. Backed with landscape ties. We bring the horse manure there, turn it regularly and use it on the garden.

[Laurierace]

Do not put fresh manure on your vegetable garden.

[2DogsFarm]

The “white” you are seeing could be ash.
My piles get so hot composting that there is often a layer of ash underneath the dry top layer.

And the “smoke” is most likely steam from the heat of composting when you expose the layer that is heating up.

Unless you smell smoke - like when you burn something - or a smell like rotting greenery, your pile is not likely to combust.

That said: doesn’t hurt to keep an eye on things.

Composted manure is THE.BEST for gardening.
I plant my veggie garden exclusively in the stuff and every year the beds get a little better.

[betsyk]

Years ago, I worked at a place that had a burn pile out near the manure pile, behind the barn (you know where this is going). Woke up in the middle of the night to smell smoke and see a small, straight stream of smoke rising up behind the barn. The burn pile had caught the manure pile on fire. In the end, it was small enough to put out with a garden hose and was far away from any important structures, but those shavings will get dry and burn from the outside of the pile, toward the inside, and smolder for days if they have the right conditions.

[Alagirl]

[QUOTE=betsyk;8186036]
Years ago, I worked at a place that had a burn pile out near the manure pile, behind the barn (you know where this is going). Woke up in the middle of the night to smell smoke and see a small, straight stream of smoke rising up behind the barn. The burn pile had caught the manure pile on fire. In the end, it was small enough to put out with a garden hose and was far away from any important structures, but those shavings will get dry and burn from the outside of the pile, toward the inside, and smolder for days if they have the right conditions.[/QUOTE]

My Grandma managed to do that, during a drought year no less.
Thankfully the neighbor had the cow manure barrel filed and hooked up, because they had not enough water to hose the pile down!

[subk]

The grey stuff you are seeing in your compost pile is most likely NOT ash. It is actinomycetes, a type of soil bacteria that very commonly grow in piles during the thermophilic (heating) phase. It is a sign of a healthy pile and a good thing! They emit an enzyme that helps to break down some of the tougher debris in the pile.

https://www.google.com/search?q=actinomycetes+in+compost&client=safari&rls=en&source=lnms&tbm=isch&sa=X&ved=0CAcQ_AUoAWoVChMIia6h0uCIxgIVwSesCh311gDF&biw=1142&bih=675

Yes, spontanious combustion of compost can happen, however statistically you are more likely to get hit by lightening. Combustion, if it is going to happen, happens in very large piles, not the size piles generated from a small farm and certainly not in compost scattered on the ground!

Any “smoldering” you see is also likely not smoke but steam. While I wouldn’t want a compost pile against my barn, worrying about it combusting doesn’t even make my radar. With horses there are so many other worst case scenerios I can waste my time stressing over than that one!!

[newhorsemommy]

I used to board next door to a place that had a manure pile catch on fire. It was a huge pile, and located quite close to the barn. The fire department was there for hours spraying it, and the horse owners were quite pissed as they had been warning the BO it could happen.