[arcticranger]

Trees are being chipped in my area and I've had a 4-5 loads dropped off for use in some landscaping work. I have two piles about 6ft high and thought that was great until a friend warned me of spontaneous combustion.

How big a pile is at risk of this? Right now I can definitely reach inside and feel mild heat. Also, if these are too big should I just make a bunch of smaller piles?

 

[Colbyt]

I've experienced it getting warm. I've seen much bigger piles weep smoke. I've not seen but heard of large piles combusting. I would not store it close to any structures.


All of these depend on the contents and the amount of green material.



I would make smaller wider plies and turn it every now and then. That is why composting is so much work.

 

[joecaption]

It's never going to get hot enough to catch fire!
If that was true every saw mill would have burned down long ago.

 

[arcticranger]

It's never going to get hot enough to catch fire!
If that was true every saw mill would have burned down long ago.

There are loads of examples of wood chip piles bursting into flame. The organic breakdown causes heat which can self ignite. I dug into the first pile on my property and saw actual smoke coming off gray ash, which doesn't make sense since it was just dropped off.

 

[joecaption]

I've been on three different rural fire dept.'s since 1971 and never once did we get a call to put out a mulch pile.
The local pulp mill has piles 100 ft. tall and not one has caught fire.
I could see it possible happening if someone covered it with a tarp so it held in the heat.

 

[Cedrus]

Where are you located.....what trees were chipped and is it just raw wood or are there leafs, twigs and branches, also ?

 

[DoomsDave]

@arcticranger, where are you?

That appears to be a key question to respond to yours, a very good question.

 

[arcticranger]

@arcticranger , where are you?

That appears to be a key question to respond to yours, a very good question.

Thx.

I'm in Sullivan County NY, climate zone 6

The nearest small cities are Monticello NY and Honesdale PA

 

[arcticranger]

Where are you located.....what trees were chipped and is it just raw wood or are there leafs, twigs and branches, also ?

It's a mix of hardwoods and a lot of pine, entire trees including pine needles, prob no leaves at this point. It's a much needed NYSEG project to remove trees obstructing their power lines.

 

[arcticranger]

I've experienced it getting warm. I've seen much bigger piles weep smoke. I've not seen but heard of large piles combusting. I would not store it close to any structures.


All of these depend on the contents and the amount of green material.



I would make smaller wider plies and turn it every now and then. That is why composting is so much work.

I am doing as you suggested, smaller piles turned regularly until they're used. There are some green pine needles but the bulk is bare wood chips. As I wrote below I raked into one pile and saw actual smoke, looked closely to be sure it was smoke not dust or something else. My biggest pile was about 9 feet high.

 

[Colbyt]

I am doing as you suggested, smaller piles turned regularly until they're used. There are some green pine needles but the bulk is bare wood chips. As I wrote below I raked into one pile and saw actual smoke, looked closely to be sure it was smoke not dust or something else. My biggest pile was about 9 feet high.

Better safe than sorry. I have seen the fire department called to a local pro composting yard. Do keep in mind they had manure and a lot stuff mixed into really big piles. That increases the risk.

 

[Old Thomas]

I would be more concerned about an infestation of carpenter ants.

 

[arcticranger]

Well to close this out: I dug into the main pile and reaching in was like a hot cup of coffee, it almost hurt. It was super compressed due to weight with lotsa smoke coming out of the holes I dug. I get now that it was the breakdown of the organic material and a friend said don't worry. I decided to worry and spread the huge piles out to a depth of 2ft or less.

It also was dropped near the road where any bratty kid could toss a cigarette so I moved it away from there.

 

[chandler48]

@jbfan may remember Bunyon Enterprises spontaneous combustion fire. They had many domes of pine bark, all smoking. They kept them turned and watered to prevent it, but one just exploded one night and it was history. It was their business, but it just happened.

 

[ront02769]

Knowing that you closed it out, place I go to get mulch has several piles of newly chipped pine bark mulch, maybe 30-40’ high (Depends on the pile). When the loader goes in to grab a yard or two, yes indeed white stuff that looks like smoke comes out.....but is just warm moist air. Wouldn’t even think about worrying over a couple of 6’ high piles of green stuff in the yard. Now, toss three or four rags that had lacquer thinner on them in a pile and you got yourself a fire! (Don’t ask how I know).