Healthy soil and sustainable growing

["Catherine Fenner" <c1fenner@comcast.net>]

I haven't read that in anything other then that GardenWeb thread you also
accessed. I chose to not respond there because people seemed so invested in
that belief. But I remain confused by the whole discussion and decided that
it revolved around differing definitions of "humus" and "compost".

However, I do disagree with the conclusion. Organic matter in hot soils is
depleted because there are more active microorganisms available to quickly
break them down. To conclude that because warm, humid climates are low on
organic matters in the soil is an inaccurate conclusion.

I live in a hot, dry area and have trouble keeping my soil packed with the
minimum 10 percent organic level on the south exposure. If you look on the
south side of most growing areas you'll note that there is less organic
matter. It has nothing to do with humic production or the application of
heat during the breakdown process.

Heating in compost piles is essential for quick manufacture of a finished
product and for depressing plant pathogens. The ratio of carbon to nitrogen
determines the rate that microorganisms will mineralize or immobilize
plant-available nitrogen as they decompose.

It makes sense to me that if you pile up a bunch of plant material and let
it sit without heat that it maintains a higher volume then the same starting
amount that is composted by heat and air. The microorganisms in a heated
pile break down that equal volume because they have the constant moisture
and air available to them so they can do their job. I've wondered if that is
how people are arriving at the conclusion that there is more humis present
in no-heat compost production.

Aiming for 160 degrees or above is counter-productive. If, indeed, you're
aware that you have added a virus-laden plant product you must take this
into account with both the compost temperature and where you use the final
product. It is inadvisable to spread the same persistent disease on the same
crop. That's why you find so many shortcut home gardener composting
instructions advising against adding any diseased materials to the pile.

At 160 degrees most if not all microorganisms are dead. You must
re-inoculate the finished product so that it is once again alive when you
incorporate it into soils.

You may certainly chose an inactive pile which breaks down like forest floor
products. If you're going to go through the collection, stacking and
harvesting process, however, why not aim to reduce pathogens and mix the
product so carbons and nitrogen incorporate, producing an more reliable and
nutrient-laden end product?


-----Original Message-----
All this talk about heating up the compost pile.  I have read (on an organic
garden list, sorry no other references) that more humus is produced if the
pile is NOT heated up.  This makes sense to me because it's the warm humid
climates that seem to have trouble keeping organic matter in/on their soil.

In nature, does the organic matter heat up while decomposing?

Nancy