Agriculture Reference
In-Depth Information
vs = very slow; ms = moderately slow; s = slow; m = moderate; r = rap-
id; mr = moderately rapid; vr = very rapid
To convert between % P and % P O : % P × 2.29 = % P O , % P O ×
2
0.44 = % P
5
2
5
2
5
To convert between % K and % K O: % K × 1.2 = % K O, % K O × 0.83 =
2
% K
2
2
Animal manures.
Historically, animal manures have been a valuable source
of organic matter and macro- and micronutrients, and they remain so today.
Economics and governmental rules, however, have changed how we obtain
and use manures. Large, integrated orchard and livestock operations are
quite rare today. Even 60 years ago, operators of such enterprises often
found they were making money on the fruit but just breaking even on the
livestock and were essentially working very hard for manure. Larger growers
usually find it most effective to specialize on their orchards and let someone
else produce the livestock and manure. Separating crop and livestock oper-
ations creates transportation problems, however, and raises the cost of ma-
nure products unless the livestock operations are very close. Integrated mar-
ket and home orchards and livestock production are still common.
The nutrient content of fresh manures varies according to the kind of an-
imal and what the animal has been eating. As manures dry and age, leach,
or are composted, nutrient concentrations are reduced, but so are the salt
concentrations and the chances of burning plants. Fresh manures also con-
tain large amounts of water, making them difficult to handle and expensive
to transport. They can damage plants by providing too much nitrogen too
quickly, and the high concentrations of salts in fresh fertilizers can build up
in soils.
