The daily banner. (Cambridge, Md.) 1897-2008, 1916-03-04
AGRlCULTUREDEPAR
NOT ENDORSING FELDSPAR
Attempts Have Been Made to Create
The Impression That The Agricul-
tural, Department Has lndorsed
Use OF Feidspar as Substitute for
Potash Salts.

Washington, D. c.. March A.
Wide publicity has recently beel
given to statement advocating th'
/ use of ground feldspar as substi
tute forspotash salts and referring tt
U. S. Department of Agriculture Bull
iletin Nc. 104 as authority for the
proposes practice.
| Bulletin No. 104. entitled "Tht
Use of Feldspathic Rocks as Ferti
lizer," was published in 1907. Thi:
bulletin discussed the use of finely
ground Teldspar as possible substi
tute fol potash for fertilizer purpo
ses, and was based upon a series OF
experiments conducted by the De
inconclu siye, as the following quota
| ton froiu the bulletin itself will
show:
"A careful reading of the forego-
ing pages will show that no claim has
been made that ground feldspar is an
efficient substitute under all circum-
stances .or potash salts. The ques-
tion is still open, and systematic and
long copIinued experimentation is
the only possible method OF obtain
ing conclusive information on the
subject. At the present stage of the
Investigation it would be extremely
unwise for anyone to attempt to use
ground rock except on an experiment
tai scale that would not entail great
financial loss. 1t is extremely un-
likely that ground rock will ever en-
tirely displace the use of potash
salts, for its availability must newt
ably depend upon many modifying
conditions, such as the nature of the
soil, the amount of moisture present,
the character Of the other fertilizers
used, and the varying root action of
different crops"
Investigations made since the pub
lication OF this bulletin have failed
to show that ground feldspar is of
any general value for fertilizer pur-
poses. The potash content in field
spathic rocks is in highly insoluble
form and to be made available for
fertilizer purposes must undergo
chemical treatment at high tempera-
lures. In general, it may be said
that most soils contain considerable
amount Of potash in this insoluble
form derived from the disintegration
Of silicate rocks, of which feldspar
is one. The application of ground
feldspar, therefore, in most instances
means merely the addition of an in
gredient already present in the soil in
considerable quantity. Many pro-
cesses for rendering the potash in
feldspar arailable have been propos-
ed, but to be commercially success
full under normal conditions a mar
ket must be found for the by-prod-
duct, andIup to the present time no
satisfactory solution of this problem
has been cached.
There ire numerous substances
the appl cation of which the soils
will, unde certain circumstances and
with part isular soils, bring about in
creasedezlEp. Yields Ground feldspar
may be Included in this class. How
ever, the cases where increased yields
result from the application of these
substances are so rare and the condi-
tions under which increased yields
may be expected are so little under
stood that their use as fertilizer ma
terials in general cannot be recon-
mended.
The Department has recently re-
ceived many requests for copies of
Bulletin 1O4 and many inquiries
with reference to the use of feldspar
as a fertilizer. The farmers of the
country should be warned that the
Department does not recommend
such practice and that the expen-
diture of money for ground feldspar
as substitute for potash for ferti-
Izer purposes will probably not re-
suit in any commensurate increase in
crop yields.