The Idaho Republican. [volume] (Blackfoot, Idaho) 1904-1932, 1912-09-13
ALFALFA YIELDS DIMINISHING.
Many of the alfalfa fields Of ea

as large crop this season as was ex
|pected. Especially was this true o
that portion Of the territory wher
Irrigation was not used. The nexi.
seeded fields (wheGe alfalfa has no
been previously grown) as well a
the fields where the crop has beer
grown for the past three or four year.
did not return the yield they should
| The writer recently had occasion t.
visit a number of fields in Latah enc
Nez Perce counties, Idaho, and Witt
man county, Washington. The plants
growing in fields which were sowa in
the spring of 1911 Except those hav.
ing grown alfalfa before) were small
yellow, and unthrifty. Dotted here
and there were single plants or small
groups of plants more thrifty than
the rest. The foliage was green and
much larger than the surrounding
growth. Upon examination the thrift
ty plants were found to have large
number of nodules on their roots.
These nodules were found to be lack
ing on the yellow, unthrifty plants.
There apparently was not sufficient
number of bacteria in the soil to in
oculate more than few of the plants
with the nodule-forming bacteria.
Artificial methods of incubation
may be used on ground that has
never before grown alfalfa. Soil on
which alfalfa has previously been
grown is drilled in with the seed at
the rate of from 200 to 500 pounds
per acre. 1t is often necessary to
dry and pulverize the infected earth
before it can be mixed with the seed
or run through the drill. This work
should be done in a darkened room.
as exposure to light for a short time
will destroy the nodule-forming bac-
terra. The plan of broadcasting in
fected soils gives good results when
the ground is thoroughly covered.
Either this method when thorough,
or that of drilling will insure results.
The soil must be drilled in with the
seed. Pure cultures of nodule-form-
ing bacteria may be secured from the |
United States Department of-Agricul-
ture. These pure cultures come in
hermetrically sealed tubes and multi
ply rapidly when placed in water con-
tanning certain nutriments. A large !
of seeds may be inoculated
with a small quantity of the mater.
lal. The bacteria will spread from
the few! plants in the newly seeded
fields to the entire field within year
Or two without other effort on the
part of the grower if the land is well
nanured each fall and cultivated both
n the fall and spring. Fields that
lave been in alfalfa for two or more
years were found to be we'll inocul-
tied with nodule-forming bacteria. !,
The diminishing yields from the old !,
# fields were found to be due (1) to
,oor cultivation or lack of cultivation
lltogether; (2) to the lack of fertil-
alton; and CD = the crowding of
he plants the first year, the stand
'eing too thick in many cases. The
tand. of course, grows thinner each
ear. v
The old alfalfa fields should be cul- q
ivated at least twice each year, once
n the fall and again in the spring. A {
borough cultivation in the fall loos- '
ms up the the ground SO that the {
vinter's moisture can penetrate deep .
Y into the soil. The spring culti- {
alton conserves the moisture for the I
Sc of the plants during the growing r
eason and at the same time destroys 9
he weeds A double cultivation with =
ither disk or alfalfa renovator fol- ;
,wed by dray harrow is necessary
} accomplish this result.
Few crops draw as heavily upon the
of the soil as does alfalfa. e
or this reason it is absolutely nec- S
ssary to put back onto the land some p
ort of fertilizer, if good yields are
be maintained. 1t Is true that the
laflfa plant with the assistance Of
le nodule-forming bacteria is able to
Ike some of it's nitrogen from the
If. Nevertheless it draws on the
otassium, phosphorus, and lime of G
le soil as heavily as do other culti- =
ated crops. The application of s or .
tons Of barnyard manure per acre
efore each fall cultivation in many .
stances will double the yield. r
1t seems to be the general Impress
n that from L. to 15 pounds of al l
Ylfa seed is necessary to insure a :
bod stand. AS result the plants Z