Pullman herald. [volume] (Pullman, W.T. [Wash.]) 1888-1989, 1910-06-03
Fertilizer Needs of Washington Soils


native or virgin fertility is not yet
exhausted. There are, however,
many different types of soils in the
state. some of which do not natur-
ally contain very large supplies of
the different elements of plant food
needed by crops. Such soils are like
Nv soon to run OUT and need APP
plication of fertilizers carrying the
particular elements in which they are
deficient.
Other soil which carry fairly good
supplies of different elements or
plant food have been improperly
handled or wastefully cropped until
badly out of condition. These can
best be restored to or built up in
fertility by the use of fertilizers to
stimulate increased growth until the
soils can be properly brought back
into good condition. Fertilizers may,
therefore, be used for two separate
purposes; namely, the application
of some one or more single ele-
ments of fertility to correct defici-
encies in those particular elements
rthe application of a complete mix
ed fertilizer to stimulate crop
growth.
The only possible means of deter
mining whether fertilizers for either
of these purposes can be profitably
used is by field experiments. A che
micial analysis of the soil indicates
the total amounts of plant food which
are present but does not show how
much of this is available for the
use of different crops nor does it
prove whether the use of any given
fertilizer would yield enough in
crease in crop growth to pay for
the cost of the fertilizer. Field trials
with fertilizers are. therefore, the
only conclusive evidence of their
value.
But chemi cal analysis do indicate
which element are likely to be def
cient because of an insufficient to-
tai supply. The State Experiment
station has completed soil survey
| in the course of which samples of
every type of soil found in the state
! have been analysed. The following
brief statement of the conclusions to
be drawn from these analyses will
serve as a bsais for field experiments
with fertilizers on the different types
of soil mentioned.
Reclaimed tide flats are usually
we'll supplied with all essential ele-
ments of fertility but are likely to
be sour" because of excess of or
ganic acids resulting from the de-
cay of large amounts of organic mat
ter. They, theGvfore, generally need
lime as a fertilizer to correct this
acidity.
| The red-fir uplands or second
bench lands usually contain fairly
good supplies of mineral plant foods
but limited amounts of humus and
need the blowing under of some
clover crop or the addition of a COM
plete fertilizer.
Alder bottom lands are rich in de-
caying vegetable matter but usually
low in phosphorus and lime.
The potash content of all soils west
of the Cascade Mountains is usually
low and for those crops like fruits
and vegetables which need large
proportions of potash fertilizers car
rying potash are generally very be-
neficial, Phosphorus is usually pre-
sent in sufficient quantities in up
land soils but likely to be deficient
in the lower lands Nitrogen is pre-
sent in abundance in the bottom land
soils but often deficient in upper
gravelly or clayey soils particularly
II they have grown large forests of
fir and pine.
Specials types of soil such as shot
clay, beaver dam, gravel prairie, etc,
require special treatment. Marshy
bottom lands, whatever the type, are
almost invariably sour because of an
excess of decaying organic matter
and lack of lime. Shot clays are usu-
ally strong soils ordinarily carrying
a good supply of phosphorus and nj
trogen but apt to be somewhat def
cient in potash. The percentage of
lime is rarely very high but seems
in most cases to be sufficient for
plant needs. The blowing under of
Vetches or clovers gives specially
good results on this type of soil.
The sage brush soils of the irri-
gated valleys east of the Cascade
mountains are very rich in lime,
carry fair supplies of potash and
phosphorus and are very low in nj
trO2pO and hnnuo Tb, r -.