The Delta independent., 1911-10-20
How To Deal With Soil Dis
eases or Willis of Potatoes.

How To Deal With Soil Dis
eases or Willis of Potatoes.
By C. H. FINCH.
l take it for granted that we have
been introduced by name to fusar-
ium and rizoc this summer. They
are like the devil-we may as well
know them when we see them or
hear their names-and beware.
There are no cures for these
We can only SO lay our
PLANS with wisdom as to avoid them.
Happy are we if we learn from some
other fellows losses and not from
our own.
The first rule is to properly ro-
tate our ground, and not to raise
potatoes but once after potatoes
and never more than two crops OF
potatoes in all until the ground has
been in peas or clover or alfalfa for
two years or more.
The second rule is to keep live
stock for the added benefit to the
fertility and physical conditions of
the ground.
Then third, to get and store prop
erly, sound seed.
Fourth, take care of the moisture
conditions of the ground before
Flowing and planting. so that the
plants start we'll.
Fifth, plant as late as is safe
for your location, so that the It's
sues will not reach the danger per
iod too early.
Sixth. practice the Greeley sys-
TEN of close, deep cultivation, and
make the seed rows tremble the
first time.
Seventh, be backward with the
water, especially on flat lands in
warm weather.
Eighth. be patient, don't plant too
many acres: don't over-crop.
Ninth, remember that potatoes
On heavy or wet soils are gamble.
Don't paint on such soils more acres
than you can afford to lose.
Tenth. have good luck. light show
ers. cool weather, no heavy rains.
The first nine will take care of
the tenth. but the tenth is a well
come addition to the best Of farms
Potato BIights.
BIights or diseases located in the
leaves of potatoes are unimportant
in Colorado. OF the two of import
ance elsewhere, We have only the
early blight. Late blight We do not
have at all. nor is it serious west
of New York.
Late blight seems to have lived
with the potato in the Andes before
1t was used by man. The disease be-
came a factor at times in Europe
soon after the potato was intro
duced. Late blight caused the fam
ines and precipitated the political
agitation and the emigration from
ireland that has so reduced the
population of that country. The
disease effects the leaves and the
stems and may drop whole fields
ro,ting and stenching on the ground.
II potatoes are dug too soon after
late blight appears the disease may
also rot the tubers-
Early blight appears but seldom
at Greeley where the crop is grown
late to avoid fungus trouble of the
kind.
In the mountains where potatoes
are earlier. early blight may become
important in July or August. The
mold or fungus that causes early
blight attacks the leaves in spots,
often spreading in concentric cir
cles.
The spots become brown or black
and often drop out. The trouble
becomes serious if too much leaf
surface is lost.
Spraying for Potato Blight
Spraying with Bordeaux mixture
is preventative and not cura-
tive measure. 1t must be done be
fore the the attack is expected and
before il can be seen. Even so TAR
east as Wisconsin. it has seldom been
found profitable to spray. In New
York and Maine it pays to spray
even when the disease does not be
come visible; although the operation
costs from So to $40 per acre for
the season. Spraying may some
times be profitable in our noun
tains on early lots of potatoes, and
may be tried in fruit regions where
the apparatus is available. 1t shoulu
begin when the potatoes are SIN III
ches high and continue at Intervals
of seven to ten days for three OF
four times. On late potatoes IN
New York, six or eight sprayinEs,
or even fifteen or twenty are use"
by some, and they told me in Maine
that some growers We're coming L"
use the three-nozzle-to-the
sprayer to cover the stems an"
under sides of the leaves, not alone
the upper sides.
Spraying is of no use whatever
for willis or soil diseases, rs the