The progressive farmer. [volume] (Winston, N.C.) 1886-1904, 1899-05-30
No Is
COTTON RUST.

! The rust Of cotton ia produced by
the growth of microscopic fungi. The
! attacks of the fungi are generally in,
duced by any sudden check to the
functions of the plant resulting in a
lowered vitality. These fungeld forms
are variously known as black rust,
yellow Leaf blight, and Mosaic disease.
II may usually be prevented by the
amelioration of the soil conditions,
such as giving better drainage, and ap-
plying the plant food in suitable
amount, and especially by applying
fertilizers with a high percentage of
potash, writes F. s. Earle, in an Ala
Oama bulletin.
1t has been well demonstrated, not
only at the Alabama Station, but in
the experiments in soil improvements
in the South, that the cheapest and
most available method Of s3il improve
ment, is by growing the COW pea in
regular rotation with the cotton and
other crops, so as to increase and main
tain the humus contents OF the soil,
and to furnish the needed nitrogen at
a lower cost and in greater abundance
than would usually be applied in q
fertilizer, and by gupplementing the
leguminous crops with the mineral
fertiliz RS in the form of phosphoric
acid and potash, and by the equally
important means of renewing humus,
by the feeding Of these legumes to
stock on the place and saving and ap
plying the manure thus made, broad
cast on the land Where a regular 70.
tation is practiced and the soil dressed
oDca in each round with home. made
manure and the peas helped with the
mineral fertiLiz3 z3rs, there will be rapid
up grade improvement in the fertility
of the soil, and in the production of all
crops, and such vigor will be given to
the cot5o ION that rust and all kindred
diseases will be Of rare occurrence. On
the sandy soils that are particularly
deficient in potash, it has been found
that an application Of potash, in the
form Of kainit especially, acts almost
as a specific egainst the attacks of
rust. While the general opin ion seems
to be trat kainit is the best form, the
present bulletin gives the opinion that
auIphate OF potash, nuriate of potash
and kainit seem to be cqIally effective
III proportion to the percentage Of pot
ash they contain. If this be true, then
the more c0ncentrrted forms are the
cheaper to buy, since in freighting
kainis that has but 12 per cent. Of pot
ash, the actual potash soon gets much
more costly than in freighting sulphate
or muriate that has 50 per cent. Of
actual potash. The muriat8 is usually
the cheapest form in which to buy
potash
The disease is very common and
makes serious injury on the sandy
soils Of Central Alabama. 1t causes
the spotting and premature falling Of
the leaves, and as healthy leaves are
essential to the performance Of the
vital functions Of the plant, their loss
gives a serious check to the crop, and
greatly shortens the growing season,
and reduces the truiCfulness of the
plants. The disease is not a true rust,
such as attacks the small grains, but
being the accepted popular name it is
used so that the disease may be under
stood. The popular name rust is used
to indicate the disease made by several
different forms Of fungi, and the study
of the disease and it's prevention have
occupied very properly the attention
Of the investigators, not only in Ala
bama, but in other cotton States. The
former botonist Of the Alabama Sta
ton, now at Cornell Station in New
York, Doctor Atkinson, has studied
the diseases and has published bulle.
tins in regard to them. He says in re-
gard to the Mosaic disease and yellow
leaf blight that "the later stages Of
this disease probably form the larger
part of the troubles which are termed
BLACK Rust" He found that spray-
ing with Fan Celeste, Bordeaux mix
ture and copper sulphate was ineffect-
ual in preventing the rust, and the ex-
periments confirmed the conclusion
that it was induced by physiological
causes. In an experiment on three
plats on which COW peas had been
grown, kainit and acid phosphate were
applied without any nitrogen on one
plat. Another had nitrate of soda and
acid phosphate, but no potash. An
other had q complete fertilizer. There
appeared in July a yellowing of the
foliage on first plat, but not the pecu-
liar appearance Of the disease, and