Freeland tribune. (Freeland, Pa.) 1888-1921, 1902-09-17
Effect of Fertilizers.


any other crop, yet the matter of ap-
plying manure or fertilizer to the po-
tato crop is one on which growers diff
fer materially. 1t is possibly the case
that many varieties, as well as the
peculiarities of soils and climates,
may have much to do with the lack Of
unanimity among growers, but it is
safe to claim that there is wide field
open for work in the use of plant foods
for potatoes. The same difficulty pre-
sents itself in Europe, where expert
ments have been conducted for years.
Professor Wright of the West
of Scotland 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 quantity
when supplemented with fertilizers.
The use of fertilizers alone will also
give large crops. In this country the
use Of barnyard manure in some sec
tions induces disease among the tu-
bers and vines. Experiments show
that the increase produced by manure
on potatoes is entirely in tubers OF
large size, the yields of small tubers
while light dressings of manure pro-
duce a much greater proportionate
effect, and a larger local return can
be obtained from limited quantity
over a given area. Fertilizers when
added to large dressings of manure
are not so effective as when added to
small dressings. Heavy dressings of
manure, without fertilizers, give pota-
toes of rather watery or inferior
quality, light dressings being less in
furious, while the use of fertilizers
with manure tends to greatly improve
the quality, but potatoes of the best
cooking quality and possessing the
highest 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
barnyard manure, increased the dry
matter in starch in the tubers, and
thus improved the quality. 1t also in
creased materially the proportionate
yield of large potatoes, which adds
to the market value of the crop. The
most profitable quantity of potash to
apply, according to the results OF eX-
periments, is 81 pounds per acre, repre-
sented by about TO pounds of sulphate
Of potash, any increase in that amount
being not so beneficial or profitable.
1t is possible to use more potash and
secure larger yields, but the amount
mentioned will give the most proht
in proportion to expense. When fertln-
zerS only are used the potash should
be given in the form Of sulphate Of
potash. In these experiments the finest
quality of potatoes were grown with
the use of sulphate of potash. kainit,
applied in the spring, whether given
with or without barnynrd manure,
gave inferior results, both in yield and
quality of the tubers, proving some
what detrimental to the quality. Mu-
riate of potash gave good results when
used in fertilizers, but when applied
with barnyard manure it proved even
more effective than sulphate of potash
in increasing the yield, but did not pro-
duce tubers of the highest quality. Nj
trate of soda, applied as top dressing
at the rate of 112 pounds per acre, and
put on Immediately after the first
wedding of the crop, produced no in
furious effects on the quality of the
potatoes.
In the growing of potatoes the farm
er desires the largest possible yield
and the large majority of them have
succeeded in SO combining barnyard
manure and 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 differences in yields.
Kainit, which is a crude sulphate of
potash containing large proportion
OF common salt. is used ex-
tensively in the manure heap
in order to prevent the loss
of volatile matter, and it increases
the value of manure for some crops,
but when applied to potatoes it does
not improve the quality. Wood ashes,
which are rich in potash when pro-
duced from certain hardwoods, would
no doubt prove valuable for potatoes.
but. as ashes also contain lime, the eff
feet may be to injure the crop, as it is
not known that lime is favor
able 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 sulphate Of potash has given sat
isfaction, the superphosphate contain
ing sufficient nitrogen if the soil is al
so fertile. Farmers should experiment
with small plots in order to test the
advantages of the plant foods for in
creasing the quality Of the tubers, as
any experiments made with certain
varieties and on soils that are varia-