9xed in their root nodules. (The nitrogen is taken from
the nodules in the seed-formation process. You can tell
whether the nodules have 9xed nitrogen by cutting one
in half with a 9ngernail. If the inside is pink, they have
fixed nitrogen.) This is a way to bring unworked soil into
a better condition. These plants provide nitrogen without
your having to purchase fertilizer, and they also help you
dig. Their roots loosen the soil and eventually turn into
humus beneath the earth. Fava beans are exceptionally
good for green manuring if you plan to plant tomatoes;
their decomposed bodies help eradicate tomato wilt
organisms from the soil.
However, we 9nd that green-manure crops are much
more e<ective when used as compost materials, and
their roots still have their good e<ect in the soil. There
are several reasons for this. Due to their high nitrogen
content, green manures decompose rapidly and even
deplete some of the soil’s humus. Another disadvantage
of the green manuring process is that the land is not
producing food crops during the period of cover crop
growth and the 1-month period of decomposition.
Additionally, green manures generally produce only
about one-quarter the carbon in a given area that
carbonaceous compost crops do, and carbon in the form
of humus is the most limiting and essential element in
maintaining sustainable soil fertility (by serving as the
energy source for microbial life and holding minerals in
the soil so they cannot easily leach out of it).
The advantage of the small-scale GROW
brent
(Brent)
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