Composting of wood requires nitrogen. Nitrogen applied to the pot will be quickly used by the microbes breaking down the wood, making it more difficult to provide nitrogen to your plants. I suppose one could compensate by providing more nitrogen, but how do you tell how much the wood composting is using, but not burn your plant's roots? Not a balancing act I want to try to attempt.

And adding that nitrogen to compensate will cause the wood to break down faster than bark ever will.

It's not worth trying IMO. There are significant reasons that bark is used as a component in all sorts of potting media, but wood chips rarely if ever is.

Pine park is almost an organically inert material that has been DEAD and weathered for decades. So in a 5-1-1 environment it will not change drastically.
Wood chip , OTOH, is mostly made from small limbs, branches, mostly consisting of LIVE green cells and thus it will readily change in composition(rot , compost).

That is why, it is widely believed not to use it container soil, EVEN IN THE GARDEN SOIL before it is composted.

So for 5-1-1 mix, best is NOT to use it and EVEN avoid any pine bark product with too much sap wood.

I'm not that convinced wood really pulls that much nitrogen out of the mix. I do agree bark is better as it last longer, and is not there as a primary food source. I know conventional wisdom all say exactly what was said above. But then we have the old ways, like hugelkultur. I have tried variations of hugelkultur technique and must say it seems to work. I didn't see any nitrogen deficiency in the plants under a normal fertilization regime. All I saw was robust growth. I now use the technique for all new beds.
Another similar technique is lasagna gardening, or straw bale gardening.
This doesn't really relate to container culture, it relates to how severe is the nitrogen tie up in gardens. It does have value to container gardening, you may not really need to remove the sap wood.
Still I would not add sap wood, as it not going to last, only add as a possible mulch.

"I didn't see any nitrogen deficiency in the plants under a normal fertilization regime."

Yeah.... I don't think you are supposed to feed Hugelkultur beds :) Organic and ferts is a bit self defeating. Hence the reasoning behind "first year" plants in the regime.

And why not try it? Fool around with one pot. The worst that can happen is you tried something different.

I didn't see any nitrogen deficiency in the plants under a normal fertilization regime.Apples and oranges. 1) you didn't increase the surface area of the wood upon which microbes would work many thousand fold (a largely unnatural condition), and 2) you didn't subject all the roots of the plant to grow only inside the accelerated decomposition of wood.

Can you name one commercial mix, other than for fungus growth, that includes uncomposted wood as a significant ingredient?

With raw woodchips (sapwood), there is an increased chance of Nitrogen immobilization, rapid decomposition and thus compaction of the mix, as well as the potential for heat-spikes in a container as a result of that decomposition. I've even had signs of nutritional deficits when using uncomposted bark, but I've finally learned how to provide the right amount of fertilizer in compensation.

Hugelkultur is quite a different animal for the reasons Charina outlined.

Josh

"Can you name one commercial mix, other than for fungus growth, that includes uncomposted wood as a significant ingredient? "
I can't name one that contains turface, pumice, granite or DE either. If you read what I wrote, I certainly didn't suggest using wood, only that it's significance is unremarkable.
Having some wood is also not forcing roots to grow in it.
I guess I see a difference, but not much of one. In the forrest the soil is filled with rotting wood. Mostly dead roots. I have a place next to an old growth forest, the soil is full of wood, on top and at all levels in the soil. The forest floor has roots every inch or so, I know as I'm trying to grow stuff here, and the amount of roots that criss cross, go all over is unreal. I dig with an axe. I'm finding few plants that can compete, some though. Seems dogwoods like it!
So I disagree with you that wood in soil is unnatural, it is very natural. In a forest it's the norm, not the exception.

This post was edited by Drew51 on Sun, Apr 6, 14 at 13:28

Drew, there are several bonsai soils that contain those gritty ingredients. Hoffman's, perhaps? I'm too lazy to search it right now.

Josh

You seriously cannot see a differences between pine shavings in a pot and whole logs/branches in the forest? Then I see no use in communicating.

Sounds good to me. As what you say I said, I did not, we certainly have a failure of communication.
That's true Josh some Bonsai sold do include those items.
I never advocated using wood, I think this is the third time I said that. For one it's a better mulch, it breaks down too quick, it appears to tie up nitrogen, I'm just not sure that really is much of a problem? As peat and bark are also organic material breaking down. Do they tie up nitrogen? My whole point was that is wood that big a problem in potting mixes? I would not use it, but I don't think I would go to the trouble of removing all sap wood, or should I say I would not go to any trouble, as it is of little concern.
It was a rather small point that seems to have been blown out like I'm suggesting using wood, never did that, please don't say I do, or did.
I just found it curious if such a problem, growing in decomposing straw, or the other methods I mention should be a problem too. They count on bacteria to break down the material. Are not those bacteria tying up nitrogen? I do find it confusing. Sorry but I see no difference from pine chip to dead roots, wood is wood and both are throughout the soil, no I do not understand how they could be different? Some roots are much finer than wood chips, and will break down faster. Is that what you mean?

This post was edited by Drew51 on Sun, Apr 6, 14 at 15:12

Looking at this subject I ran across an article on nitrogen retention of forest floors. Rather interesting as it appears many wooded areas act as pollution filters for nitrogen pollution yet some areas were losing nitrogen while others were not. It appears we do not understand the nitrogen cycling dynamics of forests at all. Also while researching I see some debate about if wood mulch depletes nitrogen or not? the notion that wood chips will lead to soil nitrogen depletion is wrong according to some experts.
It seems the more I searched, the more legitimate my question in this thread became. Then I ran across articles about how to use wood chips as soil amendments..I guess a very common practice, outside of Garden Web anyway!

http://www.sciencedaily.com/releases/2009/03/090316133438.htm

http://www.gardenguides.com/100322-amend-soil-wood-chips.html

http://gardenrant.com/2008/09/the-hort-guru-a.html

http://puyallup.wsu.edu/~Linda%20Chalker-Scott/Horticultural%20Myths_files/Myths/Wood%20chips%202007.pdf

My first thought in reading the start of this thread was, 'this reminds me of Drew's hugelthingy'...

I did some reading about this and it does seem like a mixed bag. I have absolutely no idea how wood chips in pots will affect nitrogen levels so I'll defer to you all on that. In the case of wood in a more natural environment it seems that there are a wide range of soil bacteria that will decompose wood and fix nitrogen at the same time. Generally nitrogen fixation works in relatively anaerobic environments as the enzyme that converts N2 to ammonia is oxygen sensitive. Buried logs, wood covered by leaf litter, etc probably add more nitrogen to the soil than they themselves contain. Rain also deposits a substantial amount of nitrogen in the soil, which is something that never occurred to me.

Anyway, this is all interesting to me. Here is another link from Wash U that I liked:

http://forest.moscowfsl.wsu.edu/smp/solo/documents/GTRs/INT_280/Jurgensen_INT-280.php

ryan

Wow, that article adds more factors to consider like nitrogen fixing plants. Interesting.
I have another problem I would like to solve. I hate throwing away any organic material, but I don't have anywhere to compost either. Currently I have a bunch of leaves. I shredded them to almost powder, and add to compost I put on top of my raised beds as mulch. Not wanting to tie up nitrogen I have not mixed them in the soil. But boy if I could with little consequence it would be a way to use them. All my beds are now mulched and I have 3 bags left! In the fall I will add more, and hope they rot into the beds while nothing is really growing. Also insulate them.

it would be nice to use them as an amendment to potting soil but it sounds like to will just rob the soil if nitrogen.
I guess I need a compost bin like yesterday! Yet something else to keep me busy argh!