In article ,
"David Hare-Scott" wrote:

Una wrote:
David Hare-Scott wrote:
I presume a 'below ground' crop is a root ot tuber and that 'well
cooked' means well composted and degraded..

Yes.

Why should the manure be well cooked in that particular case?

There is some risk that the horse manure includes fecal matter from
other animals, domestic and wild, and possibly even human feces (in
some barns this is likely, because there is no toilet anywhere on the
premises). You'll want to avoid bacteria from non-horse feces being
in direct contact with any food you may consume raw. Also, plants
will make better use of composted manure. Composting involves heavy
bacterial growth, which briefly consumes available nitrogen. The
nitrogen is released when the bacteria die off at the end of the
composting cycle.

If you are unsure of the provenance of your manure this seems reasonable. I
use the dung from my horses almost hot with no ill effects but I know what
they eat and what contaminants are about. And they always wash their hands
...er hoofs afterwards.


Solar radiation over time takes care of most above-ground
contaminations.

Many manure piles are aged yet poorly composted, due to too much
moisture and too little air. They are much improved by composting.
Whereas fresh manure is "green" matter, high in nitrogen, aged manure
is "brown" matter.
I like to compost all manure before I apply it, if only to break down
the balls.

Una

Nah, it's nature's packaging. Also one should consider that the longer it
lies around the more nutrients are lost due to leaching and volatility

Good point, the phosphates and potassium are subject to being carried
away by surface water during rains, and if not interred and sequestered
by soil moisture, the ammonia (NH3), a by product of the break down of
the amino acids, from the proteins (dead bacteria) in the manure, would
escape into the air and be lost to the soil. This is why side dressing
is less efficient than turning the manure into the soil. In lasagna
gardening, the manure is cast on the unturned soil and covered with
mulch, which provides the moisture necessary to sequester the ammonia.

David
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