pointer80
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aged wood ash use

Hello all, I have a outdoor wood boiler that I have had for quite some time and have some wood ash piles that are a few years old and was wondering if they are old enough to be beneficial to my garden. Does aged wood ash compost up after time? Thanks all.

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rainbowgardener
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Re: aged wood ash use

Wood ash doesn't exactly compost as all the compostable organic stuff was already burned out of it.

From wiki:

Much wood ash contains calcium carbonate as its major component, representing 25 or even 45 percent. Less than 10 percent is potash, and less than 1 percent phosphate; there are trace elements of iron, manganese, zinc, copper and some heavy metals. However, these numbers vary, as combustion temperature is an important variable in determining wood ash composition. All of these are, primarily, in the form of oxides.

Note that none of it is Nitrogen.

[back to Wiki] Wood ash can be used as an organic fertilizer used to enrich soil nutrition. In this role, wood ash serves a source of potassium and calcium carbonate, the latter acting as a liming agent to neutralize acidic soils.

So with all that CaCO3 wood ash is strongly alkaline. That can be a good thing if your soil is too acid. Personally I've never lived anywhere where the soil was too acid. My current soil is slightly acid, but that is what most veggies prefer. If your soil is not too acid, you would need to be very careful with the wood ash.
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applestar
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Re: aged wood ash use

If you didn't burn treated wood or manufactured wood products, especially hardwood ash is said have many uses in the garden in moderate amounts -- no more than dusting-sprinkling to work into the soil for nutrients and pH adjustment, but also sprinkled around the base of fruit trees to repel pests like borers, sprinkled in the bottom of pea trenches (add soil, then sow the peas), etc. if you get clubroot fungus that affects cabbages, etc. wood ash is supposed to super alkanize the soil which is said to be effective.

But water leached through wood ash is how you make caustic lye for cleaning and soap making, so yeah. I suppose the ash has stayed dry in the boiler all this time?
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pointer80
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Re: aged wood ash use

applestar wrote:If you didn't burn treated wood or manufactured wood products, especially hardwood ash is said have many uses in the garden in moderate amounts -- no more than dusting-sprinkling to work into the soil for nutrients and pH adjustment, but also sprinkled around the base of fruit trees to repel pests like borers, sprinkled in the bottom of pea trenches (add soil, then sow the peas), etc. if you get clubroot fungus that affects cabbages, etc. wood ash is supposed to super alkanize the soil which is said to be effective.

But water leached through wood ash is how you make caustic lye for cleaning and soap making, so yeah. I suppose the ash has stayed dry in the boiler all this time?
Yes, All I burn is clean hardwood, no treated wood or wood products. The ash I have is 5 year old piles that have been sitting outside right up to just emptied this year. Thanks.

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ID jit
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Re: aged wood ash use

The older stuff has probably had the lye leeched out f it, or the lye may have found something to react with.

Something to note about the dry, fresh stuff: Since red devil lye has become nigh impossible to get in the US since not long after 9/11, folks who brain tan, bark tan and make buckskin, use fresh wood as as a lye substitute. 1 standard size plastic trash can 3/4 full of water, stir in 1 5 gallon bucket of fresh wood ash, add fresh skins so they can flop around a bit, stir once or twice a day and in 3 -5 days you will have a horrible smell and the fur/hair will lift ('slip') right off the hide. The process is called "bucking".

Bucking and tanning a few skins changed how I look at and deal with fresh wood ash.
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