Bark Mulch

[southernsis]

We have just cut down about 7 oak trees and want to chip, mulch the sall limbs. Our question is will the chips catch fire if we pile it up? I know from the aftermath that hay and grass will when green. Any thoughts? Thank you

[MarkAndDebbie]

I wouldn't think so. You're AK right? Not a real arid area. The tree should have lots of water in it (unless they are all dead). Are you making mulch? If so you might add some nitrogen.

drift...They clear a hundred acres a day here (Atlanta sprawl) and take entire trees through these big grinders. They pile the chips higher than the excavators. It steams by the next day.

[glenn kangiser]

Same here -- not much danger of spontaneous combustion now -- they do warm up with water and air though.  Chicken manure is a good way to add nitrogen for compost but it will then heat up pretty good.  Adding water and turning for air will speed the process.

Other than that - Oak ond other chips left alone took a year or more to start decomposing pretty nicely, with rain runoff going through them.

[John_C]

... entire trees through these big grinders. They pile the chips higher than the excavators. It steams by the next day.

Funny you should mention that.  I don't go south from Gilmer Co. too often and hadn't seen chippers like that.  After I read your post I picked my daughter up from work and passed a site where they had done exactly as you described.  I'm guessing that the ban on burning forced them to bring that thing up here.  

I found it depressing for them to clear cut a large area and grind it all up, but it's probably better than burning it.  I often see them clear a lot and burn everything.  Oak, walnut and lots of other very useable wood included.

[glenn kangiser]

A few more thoughts.

While it doesn't spontaneously combust often, for some reason piles of chips do catch fire sometimes.

Also if used as ground cover, they can catch fire.  Have to wet mine down in the garden area if we barbecue there or they start burning when sparks drop from the barbecue.

[optionguru]

Up here in NH they have a few wood chip powered electrical plants.  My buddy is a logger, he'll cut down 10 to 20 acres at a time.  The seperate out the lumber logs and then take all of the tree tops and chip them directly into 18 wheeler trailers to bring to the power plant.  He did an 11 acre job recently and got 8 loads of chips just from the left overs.

At least it's being used for something instead of left to rot which happens a lot.