Agriculture Reference
In-Depth Information
Horse manure is good food for crops as well. According to
the same source, horse manure contains 19 pounds of nitrogen
per ton, 14 pounds of phosphate, and 36 pounds of potassium.
This works out to about 1% nitrogen, 0.7% phosphate, and
1.8% potassium.
There's no such thing as a free lunch, and horse manure is no
exception. Raw horse manure can spread a parasitic
protozoan called giardia and E. coli as well as contaminate
water sources and streams with coliform bacteria. Raw
manure can also contain worm eggs that are easily transmitted
to humans, including pinworms and various species of ascarid
worms. Horse manure is high in salts, and if used excessively,
it can cause plants grown in it to suffer water stress, even if
well watered. The highest permissible rate of application of
horse manure assuming the least measurable salinity is
between two and three pounds of manure per square foot per
year.
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In addition to the above objections, horse manure
doesn't have a balanced level of phosphorus, meaning that it
should be supplemented with a source of phosphorus when
used.
Straight horse manure is also in the process of composting.
That is, the process has not yet finished. Unfinished compost
often contains phytotoxic chemicals that inhibit plant growth.
For horse manure to be directly usable as a planting medium,
it must first be well rotted, meaning it either should be
composted in a pile mixed with other compost materials such
as plant debris or should at least sit by itself rotting for a year
before use. The former method is preferable since that will
conserve more of the manure's valuable nitrogen content. The
potential problems posed by horse manure are eliminated
through composting the manure with other materials first and
