http://www.ext.colostate.edu/Pubs/Garden/07235.html

Wood ash, an organic amendment, is high in both pH and salt. It can
magnify common Colorado soil problems and should not be used as a soil
amendment. Don't add sand to clay soil -- this creates a soil structure
similar to concrete.

Wood Products
Wood products can tie up nitrogen in the soil and cause nitrogen
deficiency in plants. Microorganisms in the soil use nitrogen to break
down the wood. Within a few months, the nitrogen is released and again
becomes available to plants. This hazard is greatest with sawdust,
because it has a greater surface area than wood chips. If you plan to
apply wood chips or sawdust, you may need to apply nitrogen fe
If you plan to apply wood chips or sawdust, you may need to apply
nitrogen fertilizer at the same time to avoid nitrogen deficiency.

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http://extension.oregonstate.edu/cat...grow/soil.html

Types of amendments
Good organic amendments (additions) for garden soils include wood
by-products such as sawdust and bark mulch, peat moss, rotted manure,
grass or wheat straw, and compost. Inorganic amendments include pumice,
perlite, vermiculite, and sand.

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I use wood chips that are about 5 years old that I walk on to break
down. My garden paths are wood chip paths. Mixed with bird feeder
refuse and it is black and fluffy and smells alive. Manured the place
many times 30 years ago and the earth worms are rampant. BUT the
moles/voles/field mice are too. Just got a volunteer mouser that looks
like our deceased midnight but he is afraid of us. I don't blame it in
away as I'd have it fixed in a year.

--
Bill Garden in shade zone 5 S Jersey USA
http://www.globalissues.org/article/75/world-military-spending
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