Aberdeen herald. [volume] (Aberdeen, Chehalis County, W.T.) 1886-1917, 1916-07-28
Watermelon WILT.
No Cure For Disease, but Can Be Pre-.
vented.

No Cure For Disease, but Can Be Pre-.
vented.
A serious disease of watermelons,
known as the wilt, has for many years
been prevalent In the southern states
and has now extended westward to
the Pacific coast. having been reported
from Oklahoma. Iowa. Indiana, Mis-
souri,, Arizona. Texas. California and
Oregon. In many Sc tons the disease
Is serious handicap to the growing
of melons on large scale. not only
by destroying the growing crop. but
also by preventing the successful cul-
ture Of melons upon the same field
again in succeeding years.
Watermelon wilt Is caused by a
fungus which lives In the soil and en-
tiers the roots, plugging up the water
carrying vessels and preventing the
rise Of moisture. thus causing the wilt
Ing and death Of the plant, The leaves
of affected plants first droop. then rap
Idly wilt and soon die, the runner dy-
ing With them: Upon cutting the main
TAP root across near the surface Of the
ground it will be found to present a
yellow color In the wood, making dis.
tinct contrast with the white color Of
the healthy plant This following, to-
:gether with the wilted appearance Of
the vine, makes the naturalization of
the disease easily possible, and the
further fact that a field once infected
shows the same trouble in succeeding
years in the same or an extended area
is an additional recognition mark. All
commercial varieties Of melons appear
to be very susceptible to the disease.
The disease is spread in a number of
different ways. By particles Of earth
carrying spores Of the fungus, which
are easily scattered by the wind, by
implements used in cultivating and by
the feet of men and work animals or
stray stock passing from one field to
another. BY infected stable manure.
The fungus lives in the dead vines. and
the practice of cutting hay from water
melon fields results in some watermel-
on vines being harvested with the hay,
and this leads to the presence Of the
causal fungus in the stable. When the
fungus once gains entrance to the barn
yard, or compost heap, 1t remains there
for years. and all the manure taken
from such yard is likely to be infect
ell. BY drainage water. flowing from
infected to unaffected fields.
There is nothing that can be done to
save a field OF melons when once ut.
tackled by the wilt, but the disease may
be avoided by the following precau-
lions:
In infected districts watermelons
should never be planted on land where
watermelons have been grown within
ten or twelve years. more or less. de-
pending on soil conditions, as expert
ments have shown that the fungus
causing the disease is able to live q
long period in the ground. AS mat
ter of practical experience it is usually
possible to secure enough fresh land.
SO that an adequate supply Of water
melons can be grown in any large dis
trict without need of recourse to old
fields.
Stable manure which has become In.
fected by the use Of melon hay or ref.
use containing melon vines should new
er be applied to the watermelon crop
or to land where It Is desired to plant
watermelons later.
Fields which have received the drain
age water from infected fields must be
considered and treated as II infected.
This means that the farmer having two
fields, one Of which is on higher ground
than the other. should plant the lower
Geld first.
As far as possible live stock should
be prevented from passing from infect.
ed to uninfected fields.
Breeding resistant varieties. It has
been demonstrated by the department
of agriculture that varieties Of water.
melons resistant to wilt can be bred.
The strains thus far produced are not
recommended for general planting. but
It will be worth while for interested 10.
calities to have wilt resistant varieties
adapted to their conditions bred.