pollutant. Then, bagasse was available for nothing or next to
nothing. These days, larger, modern mills generate electricity with
bagasse and sell their surplus to the local power grid. Bagasse is
also used to make construction fiberboard for subwall and
insulation.

_Banana skins _and stalks are soft and lack strong fiber. They are
moderately rich in phosphorus, potassium, and nitrogen. Consequently
they rot quickly. Like other kitchen garbage, banana waste should be
put into the core of a compost pile to avoid attracting and breeding
flies. See also: _Garbage._

_Basic slag_ is an industrial waste from smelting iron. Ore is
refined by heating it with limestone and dolomite. The impurities
combine with calcium and magnesium, rise to the surface of the
molten metal, and are skimmed off. Basic slag contains quite a bit
of calcium plus a variety of useful plant nutrients not usually
found in limestone. Its exact composition varies greatly depending
on the type of ore used.

Slag is pulverized and sold in sacks as a substitute for
agricultural lime. The intense biological activity of a compost pile
releases more of slag's other mineral content and converts its
nutrients to organic substances that become rapidly available once
the compost is incorporated into soil. Other forms of powdered
mineralized rock can be similarly added to a compost pile to
accelerate nutrient release.

Rodale Press, publisher of _Organic Gardening_ magazine is located
in Pennsylvania where steel mills abound. Having more experience