American union. [volume] (Morgantown, Va. [W. Va.]) 1855-1859, 1858-08-06
RUST In OATS-WHAT IS IT?

Throughout the whole Southwest
crn portion Of the Union tho oat crop
has suffered from terrible blight,
which from its resemblance to the flung
Gus substance that sometimes attacks
wheat by that name, has been calledrus':
So far rs we are informed, rust in oats
has been hitherto unknown. Wehavc
never heard or read of anything of Il c
kind, in any section of the country
The fact that it is thus unusual, opens
a wide and interesting field to the ma
turalist, and in this case, to tho ento-
mologist, as it invites investigation in
q channel, SO far as we can ascestain,
heretofore unexplored. ...
While in West Tennessee, short
time since, We took occasion to examine
the blade Of the oat under q miscros-
cope, (kindly furnished us by the Baily
Troup,) and were greatly surprised
with tho phenomenon which the glass
revealed. Since then we have follow
cd up those examinations, by the aid Of
more powerful instruments, at this city,
in company with several scientific gen
tlemcn, among whom were Drs. Briggs
and Buchanan, Of the Medical Faculty.
The cause of all this destruction of
tho oat crop is living worm, too small
to be plainly seen with the naked eye.
n single blade or leaf of the oat some
times contains hundreds Of them
They lie encased in the tissues of the
leaf or blade where they have been ger.
minated, beneath the epidcrmis or thin
pellicle over the exterior portion Of the
blade, and as they progress in develop
ment the skin Of the leaf is raised into
curious puffy blisters. The growth of
tho worm subsequently ruptures these,
and it escapes to feed upon the plant.
When first released firm their covering,
they are of a beautiful, clear, red col.
or, almost transparent, but soon begin
to change color and form, getting more
opaque and dark in appearance until,
III the course of transformation, they
become black bug, with legs and wings,
when they attack the head of the oats.
Under the microscope, the dust which
remains on the leaf, closely resembles
that on the wings Of butterflies.
How this innumerable army of infni-
tesmal worms originated is yet mys-
terry. 1t is a singular fact, however,
that wherever the greatest quantity of
rain has fallen, there the oat crop has
Jared the worst. In our recent trip
through West Tennessee, we saw but
n single field ofoats, between the Miss
issippi and Tennessee rivers, which was
not total failure, or in which it would
be folly to put scythe blade. That
field was Denmark, in Madison Coun-
ty, and was sown very early. 1t is
well'known, that more rain has fallen
in West Tennessee, this season, than
in any other part Of the State: hence
the extreme wet weather must have
had some agency in the production of
this animalcule. 1t is well-known that
moisture and heat will produce and
multiply animal life, millions per hour,
and therein we judge is the secret of
this destruction of the oat crop. 1t is
one those cases of natural phenomena
which occur only at a certain stage in
tho growth of plants, and under pecu-
liar states Of temperature and weather.
1t may happen next season, or it may
not occur again for many years. South
err Homestead.