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I cut down a Douglas Fir tree last year around June and we've dried it outside with tarp on top.

I live in Seattle where it constantly rains.

A couple of days ago I tried to use some of the wood in my outdoor firepit using Duraflame firestarter and it created a lot of smoke and not a lot of fire.

I tried couple more times with different pieces but still the same result?

I bought wood moisture reader and it reads 10~16% in the middle of the woood. I don't understand why there is too much smoke and not a real fire when I think the wood is sufficiently dry.

How dry should a firewood be for ideal burn?

  • What color is the smoke? – PV22 May 24 '17 at 16:23
  • Douglas Fir is known to be very smokey and needs a lot of heat to burn smoke free. I have found it is OK as a starter only because it splits so easily its simple to make really small kindling (ideally go down to 10mm (1/2") ). Once it gets going, its great. – user5330 May 25 '17 at 1:31
  • White smoke might indicates water. Black smoke might indicate sap. – PV22 May 25 '17 at 14:31
  • it was very thick white colored smoke. Not sure if it matters, but i am going to try storing a few pieces of wood in my garage for a few days and light it up to see if there is issue with storing it outside... it hasn't rained for a week so i don't think it is an issue, but who knows – user21479 May 25 '17 at 14:40
  • @user21479 like the answer below points to, try splitting the wood into smaller pieces. – PV22 Jun 10 '17 at 3:26
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From the moisture content of the wood it is certainly dry enough to have a good fire. I would suggest that you don't have enough heat to fully ignite the gases.

Wood burns through a process called pyrolysis where heat first breaks down the solid into flammable gases, which if there is enough heat will ignite and start a chain reaction. As the flammable gases burn, more heat is generated, so pyrolysis speeds up, more flammable gases, more heat and so on, until there is no more wood to pyrolyse.

If, as the flammable gases are driven off, there is not enough heat for them to ignite, then they will just rise off within the smoke. Smoke is essentially a mixture of unburnt flammable gases, partially burnt gases, and steam.

It sounds as if you may be trying to start your fire with sections of wood that are too large, so the surface area of the wood is small compared to the volume. So the heat is enough to start pyrolysis, but dissipates too quickly for the gases to spontaneously combust.

You need to start your fire off with very small bits of wood, dry grass, twigs and progressively build up the fire with larger and larger bits of wood. You need to get a good hot base to your fire before putting on large pieces.

This is the classic fire triangle that show that you need all three, oxygen, heat and fuel for a fire:

Fire Triangle

  • 2
    In the UK we get a lot of rain too - I'm not sure how it compares but as me and my friends like to bbq maybe I can add some thoughts to this (We also burn a lot of wood in ourdoor burners such as this). Something seperating the wood/lighter from the floor of the burner is a good idea - otherwise you loose a lot of heat just heating up the metal base of the burner. Also, the air temp can affect how well things burn, if you can use a chimney starter (normally used for a bbq) to get it started this can give you enough heat to burn better. Have you removed any bark on the wood? It maybe damp. – djsmiley2k - CoW May 24 '17 at 10:40

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