compost pile does not permit this valuable nitrogen source to
escape.

There are other bacteria commonly found in soil that uptake ammonia
gas and change it to the nitrates that plants and soil life forms
need to make other proteins. These nitrification microorganisms are
extremely efficient at reasonable temperatures but cannot survive
the extreme high temperatures that a really hot pile can achieve.
They also live only in soil. That is why it is very important to
ensure that about 10 percent of a compost pile is soil and to coat
the outside of a pile with a frosting of rich earth that is kept
damp. One other aspect of soil helps prevent ammonia loss. Clay is
capable of attracting and temporarily holding on to ammonia until it
is nitrified by microorganisms. Most soils contain significant
amounts of clay.

The widespread presence of clay and ammonia-fixing bacteria in all
soils permits industrial farmers to inject gaseous ammonia directly
into the earth where it is promptly and completely altered into
nitrates. A very hot pile leaking ammonia may contain too little
soil, but more likely it is also so hot that the nitrifying bacteria
have been killed off. Escaping ammonia is not only an offensive
nuisance, valuable fertility is being lost into the atmosphere.

_Weather and season. _You can adopt a number of strategies to keep
weather from chilling a compost pile. Wind both lowers temperature
and dries out a pile, so if at all possible, make compost in a
sheltered location. Heavy, cold rains can chill and waterlog a pile.
Composting under a roof will also keep hot sun from baking moisture
out of a pile in summer. Using bins or other compost structures can