"Mike LaMana" fake@MikeatHeartwoodConsultingdotnet wrote in message ...
Folks:

1.) Be aware that the starting chemistry of the soil i questions and the
starting chemistry of sawdust both play a role in answering the original
post.
2.) C:N ratio is critical but can be misleading. For example, the C:N ratio
may be the same for raw sawdust added to soil and for highly composted
sawdust added to soil. One critical difference is with the latter a lot of
the C (carbon) will be accounted for in humic acids which are chemically
recalcitrant and do not really figure into the resources needed by soil
microbes. In raw sawdust most of the C is accounted for in long-chain
carbohydrates which are convertible.

This is against my experience. My front flower bed, for example, has
only received one foot of woodchips since 1996, and its N content is
OK, and the plants growing in it show no sign of being N-deficient.
The surrounding soil is extremely N-poor. I must conclude that
decomposing wood absorbs nitrogen from the atmosphere.

3.) The use of sawdust to amended pH in blueberries is well established, but
bear in mind that blueberries are commercially grown only in certain soil
types. Thus, examples from that use may not extrapolate well to other (e.g.
more alkaline) soils
4.) Depending on the sawdust, one may actually make the soil more alkaline.

could you comment on this, as well as point 1)? How is the sawdust
chemically different?


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