A one-cubic foot bag of dried steer manure weighs 25 pounds and is
labeled 1 percent nitrogen. That means four sacks weighs 100 pounds
and contains 1 pound of actual nitrogen.
A fifty pound bag of cottonseed meal contains six percent nitrogen.
Two sacks weighs 100 pounds and contains 6 pounds of actual
nitrogen.
Therefore it takes 24 sacks of steer manure to equal the nitrogen
contained in two sacks of cottonseed meal.
If steer manure costs $1.50 per sack, six pound of actual nitrogen
from steer manure costs 24 x $1.50 = $36.00
If fifty pounds of cottonseed meal costs $7.50, then six pounds of
actual nitrogen from cottonseed meal costs 2 x $7.50 = $15.00.
Now, lets take a brief moment to see why industrial farmers thinking
only of immediate financial profit, use chemical fertilizers. Urea,
a synthetic form of urine used as nitrogen fertilizer contains 48
percent nitrogen. So 100 pounds of urea contains 48 pounds of
nitrogen. That quantity of urea also costs about $15.00!
Without taking into account its value in terms of phosphorus,
potassium and other mineral contents, nitrogen from seed meal costs
at least eight times as much per pound as nitrogen from urea.
Newspapers, even with colored inks, can be safely used in compost
piles. Though some colored inks do contain heavy metals, these are
not used on newsprint.
However, before beginning to incorporate newsprint into your
composting, reconsider the analyses of various types of compost
broken out as a table in the previous chapter. The main reason many
municipal composting programs make a low-grade product with such a
high C/N is the large proportion of paper used. If your compost is
intended for use as mulch around perennial beds or to be screened
and broadcast atop lawns, then having a nitrogen-poor product is of
little consequence. But if your compost is headed for the vegetable
garden or will be used to grow the largest possible prized flowers
then perhaps newsprint could be recycled in another way.
Cardboard, especially corrugated material, is superior to newsprint
for compost making because its biodegradable glues contain
significant amounts of nitrogen. Worms love to consume cardboard
mulch. Like other forms of paper, cardboard should be shredded,
ground or chopped as finely as possible, and thoroughly mixed with
other materials when composted._
__Pet wastes_ may contain disease organisms that infect humans.
Though municipal composting systems can safely eliminate such
diseases, home composting of dog and cat manure may be risky if the
compost is intended for food gardening.
_Phosphate rock._ If your garden soil is deficient in phosphorus,
adding rock phosphate to the compost pile may accelerate its
availability in the garden, far more effectively than adding
phosphate to soil. If the vegetation in your vicinity comes from
soils similarly deficient in phosphorus, adding phosphate rock will
support a healthier decomposition ecology and improve the quality of
your compost. Five to ten pounds of rock phosphate added to a cubic
yard of uncomposted organic matter is about the right amount.
_Rice hulls:_ See _Buckwheat hulls._
_Rock dust._ All plant nutrients except nitrogen originally come
from decomposing rock. Not all rocks contain equal concentrations
and assortments of the elements plants use for nutrients.
Consequently, not all soils lustily grow healthy plants. One very
natural way to improve the over all fertility of soil is to spread
and till in finely ground rock flour make from highly mineralized
rocks.
This method is not a new idea. Limestone and dolomite--soft, easily
powdered rocks--have been used for centuries to add calcium and
magnesium. For over a century, rock phosphate and kainite--a soft,
readily soluble naturally occurring rock rich in potassium,
magnesium and sulfur--have been ground and used as fertilizer. Other
natural rock sources like Jersey greensand have long been used in
the eastern United States on some unusual potassium-deficient soils.
Lately it has become fashionable to remineralize the earth with
heavy applications of rock flours. Unlike most fads and trends, this
one is wise and should endure. The best rocks to use are finely
ground "basic" igneous rocks like basalts. They are called basic as
opposed to "acid" rocks because they are richer in calcium and
magnesium with lesser quantities of potassium. When soil forms from
these materials it tends to not be acid. Most basic igneous rocks
also contain a wide range of trace mineral nutrients. I have
observed marked improvements in plant growth by incorporating
ordinary basalt dust that I personally shoveled from below a
conveyor belt roller at a local quarry where crushed rock was being
prepared for road building. Basalt dust was an unintentional
byproduct.
Though highly mineralized rock dust may be a valuable soil
amendment, its value must equal its cost. Application rates of one
or two tons per acre are minimal. John Hamaker's _The Survival of
Civilization _suggests eight to ten tons per acre the first
application and then one or two tons every few years thereafter.
This means the correct price for rock dust is similar to the price
for agricultural lime; in my region that's about $60 to $80 a ton in
sacks. Local farmers pay about $40 a ton in bulk, including
spreading on your field by the seller. A fifty-pound sack of rock
dust should retail for about $2. These days it probably costs
several times that price, tending to keep rock dust a novelty item.
The activities of fungi and bacteria are the most potent forces
making nutrients available to plants. As useful as tilling rock
powders into soil may be, the intense biological activity of the
compost pile accelerates their availability. And the presence of
these minerals might well make a compost pile containing
nutrient-deficient vegetation work faster and become better
fertilizer. Were the right types of rock dust available and cheap,
I'd make it about 5 percent by volume of my heap, and equal that
with rich soil.
_Safflowerseed meal._ See _Cottonseed meal._
_Sawdust_ contains virtually nothing but carbon. In small quantities
it is useful to fluff up compost piles and prevent compaction.
However this is only true of coarse material like that from sawmills
or chain saws. The fine saw dust from carpentry and cabinet work may
compact and become airless. See _Paper _for a discussion of lowering
the fertilizing value of compost with high C/N materials.
_Seaweed_ when freshly gathered is an extraordinary material for the
compost pile. Like most living things from the ocean seaweeds are
rich in all of the trace minerals and contain significant amounts of
the major nutrients, especially potassium, with lesser amounts of
phosphorus and nitrogen. Seaweeds enrich the heap, decompose very
rapidly, and assist other materials to break down. Though heavy and
often awkward to gather and haul, if they are available, seaweeds
should not be permitted to go to waste.
Those with unlimited money may use sprinklings of kelp meal in the
compost pile to get a similar effect. However, kelp meal may be more
economically used as part of a complete organic fertilizer mixture
that is worked into soil.
_Shrub and tree_ prunings are difficult materials to compost unless
you have a shredder/chipper. Even after being incorporated into one
hot compost heap after another, half-inch diameter twigs may take
several years to fully decompose. And turning a heap containing long
branches can be very difficult. But buying power equipment just to
grind a few cart loads of hedge and tree prunings each year may not
be economical. My suggestion is to neatly tie any stick larger than
your little finger into tight bundles about one foot in diameter and
about 16 inches long and then burn these "faggots" in the fireplace
or wood stove. This will be less work in the long run.
Soil is an often overlooked but critically important part of the
compost pile. Least of its numerous benefits, soil contains
infinitudes of microorganisms that help start out decomposition.
Many compostable materials come with bits of soil already attached
and few are sterile in themselves. But extra soil ensures that there
will initially be a sufficient number and variety of these valuable
organisms. Soil also contains insoluble minerals that are made
soluble by biological activity. Some of these minerals may be in
short supply in the organic matter itself and their addition may
improve the health and vigor of the whole decomposition ecology. A
generous addition of rock dust may do this even better.
Most important, soil contains nitrification microorganisms that
readily convert ammonia gas to nitrates, and clay that will catch
and temporarily hold ammonia. Nitrifying bacteria do not live
outside of soil. Finally, a several inch thick layer of soil capping
the heap serves as an extra insulator, holding in heat, raising the
core temperature and helping seal in moisture. Making a compost heap
as much as 10 percent soil by dry weight is the right target
Try thinking of soil somewhat like the moderators in an atomic
reactor, controlling the reaction by trapping neutrons. Soil won't
change the C/N of a heap but not being subject to significant
breakdown it will slightly lower the maximum temperature of
decomposition; while trapping ammonia emissions; and creating better
conditions for nitrogen fixing bacteria to improve the C/N as the
heap cools and ripens.
_Soybean meal._ See _Cottonseed meal._
_Straw_ is a carboniferous material similar to sawdust but usually
contains more nutrients. It is a valuable aerator, each stalk acting
as a tube for air to enter and move through the pile. Large
quantities of long straw can make it very difficult to turn a heap
the first time. I'd much prefer to have manure mixed with straw than
with sawdust.
_Sunflowerseed meal._ See _Cottonseed meal._
_Tankage_ is another slaughterhouse or rendering plant waste
consisting of all animal refuse except blood and fat. Locally it is
called meat meal. See _Hoof and horn meal._
_Tofu factory waste._ Okara is the pulp left after soy milk has been
squeezed from cooked, ground soybeans. Small-scale tofu makers will
have many gallons of okara to dispose of each day. It makes good pig
food so there may be competition to obtain it. Like any other seed
waste, okara is high in nitrogen and will be wet and readily
putrefiable like brewery waste. Mix into compost piles immediately.
_Urine._ See _Manure._
_Weeds. _Their nutrient content is highly variable depending on the
species and age of the plant. Weeds gone to seed are both low in
nitrogen and require locating in the center of a hot heap to kill
off the seeds. Tender young weeds are as rich in nitrogen as spring
grass.
Weeds that propagate through underground stems or rhizomes like
quack-grass, Johnsongrass, bittersweet, and the like are better
burnt.
_Wood ash_ from hardwoods is rich in potassium and contains
significant amounts of calcium and other minerals. Ash from conifers
may be similarly rich in potassium but contains little else. Wood
ashes spread on the ground tend to lose their nutrients rapidly
through leaching. If these nutrients are needed in your soil, then
add the ash to your compost piles where it will become an
unreachable part of the biomass that will be gradually released in
the garden when the compost is used.
_Wood chips _are slow to decompose although they may be added to the
compost pile if one is not in a hurry. Their chunkiness and stiff
mechanical properties help aerate a heap. They are somewhat more
nutrient rich than sawdust.
_Wool wastes_ are also called shoddy. _See Hair._