The Marietta journal. [volume] (Marietta, Ga.) 1866-1909, 1905-11-23
State Chemist Writes About
Different Plant Food.
INTERESTING AND INSTRUCTIVE
Potash, Its Importation as Plant Food,
Sources from Which Derived-Wood
Ashes, starsfurt posits-The Acid
Phosphate Industry.
Letter No. 9.

our fathers was ashes mainly wood
ashes and while potash from this
source is a most excellent manure, yet
evidently the quantity available must
be quite limited. The great majority
of soils, especially those which contain
much clay, usually hold a large reserve
Of potash, and do not appear to require
the special application of potash as a
manure. Light sandy soils on the
other hani, and some clay soils also
appear to be quite deficient in potash
and are much benefited by applications
of that fertilizer. Soils of this ma
ture, therefore, stand as much in need
of constant potash manuring as of
phosphoric acid and nitrogen applica-
tions.
Wood-asnes, whilst they may be
cheap and easily obtained in countries
where large forest areas are to be
cleared, in older countries con not be
so easily obtained. Long before fer
tiliZers became a commercial commod-
ity, wood-ashes were highly thought of
by farmers. But usually when farm
er buys ashes, he buys in the dark,
owing to the fact that ashes vary so
widely in their contents of potash. AS
rule, the ashes from hard woods are
richer in potash than those from soft
woods. The ash of the red oak, for
instance, contains about six per cent.
Of potash, that Of the hickory about
nine per cent, some pine woods about
four and nalf per cent. No definite
percentage, however, can be laid down
for any special wood, as the same wood
will vary in different localities, and
wood OF different parts Of the same
tree will vary, the ashes from the
twigs and young limbs being riches in
potash than the ashes from the body
or trunk of the tree.
1t is impossible to fix the value of
a lot of ashes, except by special analy-
sis of the particular lot, owing to this
great variability in composition, and
owing to the further fact that the ashes
may have been leached or mixed with
more or less dirt. The average anaIy-
sis for good unleached ashes may be
taken as five per cent. of potash, one
and one-haf per cent of phospnoric
acid, and tnirty-two and half per
cent. Of lime. According to the values
for fertilizers adapted for the present
season, tor of good average ashe.
at the coast should be worth four dol
lars and fifteen cents This calcula
ton allows no value to the lime, al
though, of course, it has a decided val
ue on sucl soils as are deficient in 1t
Luckily since the middle of the last
century, farmers have been no longer
compelled to rely on ashes as a source
of potash, but have come to adopt in
their stead almost universally what
are known as the German or Staasfurt
| potash salts.
These salts are mined in Stassfurt
in northern Germany, In the province
OF Saxony. They were discovered by
the Prussisn government while boring
for rock salt about the year 1857. Al
first they were considered worthless
but soon the great Chemist Liebig be
gan publishing his discoveries con
corning plant growth and nutrition
showing potash to be an essc ntial and
muoh-needed element in the growth
and development of plants This LEI
to tae development of the potash
mines, and the utilization for agricul
ture OF the precious salts contained
| In them. The first potash salt
works for the manufacture and sale Of
the potash salts was established in
Stassfurt in 1852. Some of the crude
ores are suited for agricultural use
just as they are dug from tle mines
and are known as kainit, carnallite
sylvinit The kainit contains on ar
average of about twelve and half pei
cent. of potash, the carnallite about ter
per cent, and the sylvinit sixteen PEI
cent of potash. AS there is a great
demand for these products all over the
world, and the freightage to long dis
tances is quite an item, it became de
| sirable TO concentrate the potash In
these natural products as much as pos
siOle. so as to avoid the cost of trans
poTtatiOn on the salts contained In
them useless to agriculture.
The great factories of the German
Kali Works now prepare from the
crude kainit, carnallite and sylvinit
muriates OF potash containing forty Ave
per cent, fifty per cent, and fifty-fqVe
per cent. Of actual potash, also what is
known as double manure salts" with
twenty-six per cent. of potash. A com
plete analysis of all the various prod
ucts and some others will be found or
another page of this bulletin.
These deposits are practically mex
haustible In qEantity and Will supply
the agricultural world for many years
to come. Should they ever becomt
exhausted, doubteleSs new discoveries
will be made, and II not, potash coult
| doubtless he OhtaiDaA tho,uh -,