The farmer and mechanic. [volume] (Raleigh, N.C.) 18??-19??, 1911-12-26
E MATURING
Cow Peas

Who has not heard Of the cow PEI
as a ~hay-making and a soil iHproV
ing plant? And. who has not beer
led to believe that n third or NOR
of the nitrogen and other plant fooe
elements found in this plant at ma
turity, are left in the roots and STUB.
BILE after the crop is harvested ant
cured for hay-that is to say-out OF
every hundred pounds Of nitrogen
etc, found in the pea CROP at ma
turfty, SO 1-3 pounds are the roots
and stubble.
This was our best information ur
to a short time g n even now
some of our best agricultural advisers
insist on the proverbiaf third OF the
nitrogen, ETC., being left in the under
ground portion of the plant. Like the
old idea Of the souring Of the soil on
we'll drained land, some man seems
to have guessed at the amount OF
nitrogen, ETC., left In the root ano
stubble and fastened to rush his in
tuition into print.
Now a ton OF cured cow peas has
in the whole plant about, 40 pounds
Of nitrogen. If one-third Of this
amount were in the roots and stub
BILE we would have left on the sol
and in the soil about IA pounds OF
available nitrogen per acre in case the
acre produced a ton Of COW pea hay
This mou Of nitrogen is equal to
tina furnished by 700 pounds OF an
S-2-2 fertiiizer-a pretty heavy ap-
plication for most farm crops. This
seemed to be rather weighty argument
In favor Of cutting h vines. feedins
them to live stock. and putting the
manure back on the land regardless
of the fact that the manure from a
ton OF COW peas hay fed to cattle will
cover-well what part OF the acre viii
it covero
Our farmers have been acting ou
this advice for q number OF years ia
tility OF their lands under this svs-
tenn. Mr.. w. A. Marsh. Of Union
county took this advice literally.
sowed oats, cut and removed them,
then sowed COW "a on the oat stub
BILE and cut these for hay hen ma
ture. This practice vas continued till
his land would not produce a crop
even Of peas. Examples could be
multiplied where the pea crOp has
been removed year after year with
disastrous results. Indeed. it now
seems that the c,lrest method Of de-
plotting the fertility of the soil is to
remove a croD of COW pea vines from
it every year for q few years in sue
cession.
The real exclamation Of this pheno-
menon has finally been discovered. In
an exhaustive series Of tests and ex-
p~erirents conducted bv a number of
our best experiment stations it has
been found that the mount Of nitro
gen. etc. left in the roots and stumble
of the COW pea plant is not one-thi-f!
but ahont Hne-ferth of hat found in
the whole n1ant. Here seems to be one
of the leading factors in the exnlana-
ton of the running down of average
soils by the annual renov OF the nea
crOD. Another, and. perhaps. the
leading factor. is that all the organic
matter IS removed from the soil for
o series of wears by this method and
thus all bacterial life is driven from
the land which is thereby rendered
dead. These dead soils are not ne"es-
sari1v robbed Of their mineral plant
foods. however. as will be demon
strated by blowing down a COW pea
cron or a good crop Of rye for a year
CT two in succession.
One ton of green cow pea vines
contains ahont 5.5 hounds Of nitro:
gen: 2 pounds OF Dhosnhate. and {
pounds Of notash. It is an easy mat
ter. on averaoe soil. to get q growth
Of u tons Of some one OF the rana
growing varieties per acre. which viii
cure uD into three tons OF hay.
Cornosition of green COW pea vines
compared with composition Of fresh
COW and horse manure:
Nitro Phos-
gen. phate Pot'T
Green cow pea vines 81 2 So
Flesh cow manure. rs is 7.3
Frech horse manure. 81 10 7.3
With this WELD per acre there won1d
be produced on a ten-acre field 12f
tons of green Dea vines which. it cut
tC pieces with a sharp disc harrow
plowed under. and Thoroughly incor.
pora+ed with the whole sol! stratum
would add to this field about 65t
pounds Of NITROGEN and render avail
able go hounds of anC
about $50 pounds Of potash.
Bv thus using the pea crop as greey
hi the farmer gets from the al,
as much NITROGEN in the first t."
inches Of the soil of his 1h-acre fe,i
as he he would get from So tons o.
manure or from Is tons of an So: