Montgomery County sentinel. [volume] (Rockville, Md.) 1855-1974, 1902-08-22
agricultural.
EFFECT OF FERTILIZERS.

Potatoes are grown extensively in this
country, and more experiments have
been made with them than any other
crop, yet the matter of applying manure
or fertilizer to the potato crop is one on
which growers differ materially. 1t is
possibly the case that many varieties, as
we'll as the peculiarities of soils and eli
mates, may have much to do with the
lack Of unanimity among growers, but
it is safe TO claim that there is a wide
field open for work in the use of plant
foods for potatoes. The same difficulty
presents itself in Europe, where expert
ments have been conducted for years.
Professor Wright, Of the West of Scot
land Agricultural College, concludes
that large crops of potatoes can be grown
either with heavy GO tons) dressing
per acre Of barnyard manure, or with
half that quanty when supplemented
With fertilizers. The use Of fertilizer alone
will also give large crops. In this coun-
try the use Of barnyard manure in some
sections induces disease among the tubers
and vines Experiments show that the
increase produced by manure on pota-
toes is entirely in tubers Of large size,
the yields Of small tubers, while light
dressings of manure produce q much
greater proportionate effect, and larger
local return can be obtained from
limited quantity over q given area.
Fertilizers when added to large dress
ings Of manure are not so effective as
when added to small dressings. Heavy
dressings Of manure, without fertilizers,
give potatoes of a rather watery or in-
ferior quality, light dressings being less
injurious, while the use Of fertilizers
with manure tends to greatly improve
the quality, but potatoes of the best
cooking quality and possessing the high
est nutritive value can be grown by the
use Of fertilizers alone.
Concerning the use of the several
forms Of fertilizers on potatoes it was
demonstrated that the addition of potash
in any form, when applied with barn
yard manure, increased the dry matter
in starch in the tubers, aud thus i'm
proved the quality 1t also increased
materially the proportionate yield Of
large potatoes, which adds to the mar
ket value Of the crop. The most profit
able quantity Of potash to apply. accord
ing to the results Of experiments, is "a
pounds per acre. represented by about
ITO pounds of sulphate of potash, any
increase in that amount being not so
beneficial or profitable. II is possible
to use more potash and secure larger
Yields, but the amount mentioned will
give the most profit in proportion to
expense. When fertilizers only are used
the potash should be given 10 the form
Of sulphate Of potash. In these expert
ments the finest quality of potatoes we're
grown with the use Of sulphate of potash
KANT, applied 10 the spring, whether
/ given viii without barnyard manure,
gave iBfci results, both in yield and
quality Of tubers, proving somewhat
/ detrimental to the quality Muriate of
potash gave good results when used in
fertilizers. but when applied with barn
/ yard manure it proved even more effec-
tive than sulphate Of potash iE inOreas-
| ing the yield. but did not produce tubers
Of the highest quality. Nitrate of soda.
applied as top dressing at the rate of
1l2 pO~-an per acre, and put on imme-
diately after the first wedding of the
crop, produced no injurious effects on
the quality Of the potatoes
In the growing Of potatoes the farmer
desires the largest poss BILE yield and the
large majority Of them have succeeded
in so combining barnyard manure aud
fertilizers as TO harvest enormous crops,
but the experiments mentioned include
something more than yields. the object
being to also observe the effect on the
quality of the tubers 1t is the quality
that gives the profit, as the difference
in prices may largely Offset the differ
enCes in yields KANT, which is a
crude sulphate Of potash containing
large proportion Of common salt, is used
extensively in the manure heap in order
70 prevent ' lathe matter,
and i .rorasses al value Of manure for
some crops By. wheu applied to potA-
COOS It ice 7t improve the quality.
Wood ashes, which are rich 10 potash
when produced from certain hardW woods,
would no doubt prove valuable for pota.
toes, but, as ashes also contain lime, the
effect may be to injure the crop, as it is
not known that lime is favorable to some
! diseases, and for that reason should not
be applied. A fertilizer for potatoes
should not only contain potash, but also
nitrogen and phosphoric acid. In some
cases the use of superphosphate and sui
phate Of potash has given satisfaction,
the superphosphate containing sufficient
nitrogen il the soil is also fertile Farm.
era should experiment with small plots
in order TO test the advantages Of the
plant Goods for increasing the quality Of
the tubers. as any experiments made
with certain varieties and on soils that
are variable may be of but little advan-
tage in sections where the conditions