The Sauk Centre herald., 1912-11-14
GRAIN RUSTS.
z. III. FREEMAN. Chief Of Di-
vision of Vegetable PsehoI-
ogy, hinn. University Farm.

i. = !. :. = :. = :. !. :. :. :. :. :. :. + :.
Usually once or twice in a decade
sections OF the wheat groWin3.area OF
the United States are swept by 6is-
case which is known as rust. Epi-
denies are usually more severe IN the
spring wheat areas of the Northern
Mississippi valley than in any of the
other large grain growing districts.
In Texas, at least in the central part,
rit is even more severe than in the
spring wheat states. Not cnly are
wheatfelds infested, but the disease
is even more serious on oats. In fact
the rust constitutes prohibitive fac
tor in the growing of oats for grain
in certain Southern states.
There usually comes time, in the
progress of any given crop of wheat,
when farmers and elevator men, and
others who are interested as growers
or spectators, become. apprehensive
in regard to the outcome Of that crop.
Usually this occurs in early July,
when the first reports of wheat rust
appear in the papers. The rust is
usually present, however, in the fields
some time before the reports appear.
In fact the rust, is almost always pres
ent, and can easily be detected in the
air, at almost any time, by filtering
L, s~H
ing them under the microscope. One
will find spores of the rust in the air
| at all times from early spring to late
in the fall
to the farmer are, first, how can he
| tell if the rust will be severe, and
| second, what can he do to prevent it.
| Neither of these questions can be an
swered at the present time with en-
| tire satisfaction. Since the rust Is
always present to certain extent it
| is clear that the weather conditions
are really the determining factor in
the epidemic. The prevailing notion
| among farmers, and even among GER.
| tain scientific men, that hot, mrggy
| weather, with abundant rainfall, is
good rust weather is apparently not
| correct The rust spores grow best,
and the rust parasite itself grows
| best, in cold weather 1t has been
| found that the last two great epidem-
| les in the spring wheat states, namely
those of 1904 and 1911, were brought
on by cool spell Of weather between
| the heading out time of the wheat and
harvest. Ii this period is delayed by
a cold spell which at the same time
is the most favorable tor the growth
Of the parasite, and which further
more furnishes plenty of moisture in
/ the form Of dew, even though rain is
not present, then rust is almost sure
/ to follow Since the weather condi-
tions cannot be forecasted it is al
most impossible to predict the coI1.
ing of an epidemic.
| AS to the second question stated be-
fore-namely, the prevention Of rust
no satisfactory solution as yet has
been evolved, although tremendous
amount of work has been done, both
in this country and other countries.
on the subject Of wheat and grain
rust. In general, good farming, i'm
plying diversifcation Of CROPS. crop
rotation, good drainage and tiilage,
are to be recommended since they
give the plant a better chance of de
veloping rapidly and of escaping the
rust. Early varieties, in the case Of
wheat, may sometimes save crop,
but are not absolutely sure. Many
of the durums, or so called macaroni
wheats, are actually resistant to the
rust. These wheats are not, however,
we'll adapted to some parts Of the
| spring wheat districts, and even
where they do grow namely, in
Western North and South Dakota
the uncertain market and prejudicial
price sometimes deter the farmer
from planting durums. 1t is to be-
noticed that not all durums are re-
sistant to the rust, though some are:
while on the other hand none of the
| common spring wheats show any ap-
preciable resistance to the rust when
the latter exists in the form of an
epidemic.
| Experiment stations and the United
States government are attempting to
obtain, by hybridization and selection
and by the use of field rust plots, va
rieties which combine the resistance
of the durum wheat with the world
famous milling qualities of the hard
spring wheat. If this can be accom-
plished it will make possible saw
| ing of millions of dollars annually to
the. farmers of the spring wheat
states.