The Democratic advocate. [volume] (Westminster, Md.) 1865-1972, 1916-03-10
Ground FeldSpar Not Recommended
All Fertilizer.

Nj ferflllIer.
Vide publicity has recently been
given to a statement advocating the
use of ground feldspar as substitute
for potash salts and referring to L. S.
Department of Agriculture Bulletin
No. 1O4 as authority for the proposed
practice.
Bulletin No. lO4, entitled The Use
of teldspathic Rocks as Fertilizer,
was published in 1907. This bulletin
discussed the use OF finely ground
feldspar as a possible substitute for
potash for fertilizer purposes, and
was based upon series of expert
ments conducted by the Department.
The results reached were inconclusive,
as the following quotation from the
bulletin itself will show:
A careful reading of the foregoing
pages will show that no claim has
been maze that ground feldspar is an
efficient substitute under all circum-
stances for potash salts.
The question is still open, and sys-
tematic and long continued expert
mentation is the only possible method
Of obtaining 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 experimental scale that would
not entail great financial loss.
|. 1t is extremely unlikely that
ground rock will ever entirely dis
place the use of potash salts, for it's
availability must inevitably 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. y
Investigations made since the pub
LEGATION of this bulletin have failed to
show that ground feldspar is of any
general value for fertilizer purposes,
The potash content in feldspathic
rocks is in highly insoluble form
and to be made available for fertili-
iZer purposes must undergo chemical
treatment at high temperatures. In
general, it may be said that most soils
contain a considerable amount of pot
ash in this insoluble form derived
from the disintegration of silicate
rocks, of which feldspar is one. The
application of ground feldspar, there
lOI I, III LlOSJ illSIdHCCo HiCdAo llClCly
the addition Of an ingredient already
present in the soil i'm considerable
quantity. Many processes for render
ing the potash in feldspar available
have been proposed. but to be CONNER
cially successful under normal con-
| ditionS market must be found fol
! the byproduct, and up to the present
time no satisfactory solution OF this
problem has been reached
! There are numerous substances the
application of which to soils will, un.
der certain circumstances and with
particular soils, bring about increased
! crop yields. Ground feldspar may be
included in this class. However, the
cases where increased yields result
from the application of these sub
stances are so rare and the conditions
under which increased yields may be
expected are so little understood tha
their use as fertilizer materials il
general cannot be recommended.
The Department has recently re
ceived many requests for copies o.
Bulletin l04 and many inquiries will
reference to the use of feldspar as {
fertilizer. The farmers of the countr!
should be warned that the Department
does not recommend such a practice
and that the expenditure of money fol
ground feldspar as a substitute foI
potash for fertilizer purposes viii
probably not result in any common
surate increase in crop yields.