The Blackfoot optimist. [volume] (Blackfoot, Idaho) 1907-1918, 1913-08-14

the majority of the fields was irregu-
lar. Some sprouts were vigorous and
healthy, many were puny and just APP
pearing above ground, while many
cuttings had altogether failed to
sprout. Some of the latter sprOuted
after the June showers.
Diseased Seed Potatoes Planted
Upon digging up many of the weak
sprouts and cuttings which had no,
terminated, it was in numerous cases
discovered that the cuttings had been
infected with powdery dry rot, which
had greatly weakened or destroyed
the sprouts or had entirely rotted the
cuttings.
Ground Too Dry for Potato Planting
Much of this irregularity in the ger
mination was also due to the fact that
planting had been done in ground en-
tirely too dry. Many of the cuttings
planted in such soil failed to GERM
nate until the rains of June had fur
nished the necessary moisture. For
speedy and vigorous termination pO-
tatoes require to be in contact with
moisture
Early irrigation Necessary
Potato growers in some districts
have already been taught by exper-
fence to irrigate their fields before or
| Immediately after planting their pO-
tatoes. In many localities in the inter
mountain states the winter and spring
precipitation may be too small for
the soil to retain sufficient moisture
at planting time. 1t would be wise
i,.,.io hnfCrcs rN1o +.
ing potatoes in such districts. Thus a
rapid and vigorous termination would
ordinarily be assured.
| Much Stem Infection
Early in July the writer was re-
uuested to visit C large potato district
because it was reported that many
potato vines showed symptoms Of dis
ease. A tour over this district, as we'll
as visits to other districts, revealed
the fact that many vines appeared
weakly; some had yeliowish, upward
curled leaves; others possessed fol age
punched up in rosettes; the tips OF
still others were willing. On digging
up such plants practically all of them
we're found either to arise from rotten
cuttings, or the stems below ground
had been partly or wholly girdled by
brown or blackish rot, or both con-
ditions existed together. In some in
stances this rot had eaten through the
stem; either killing the plant, or
greatly checking it's growth. Ere
ouently plants were able to develop a
new root system above the part at
tached. Some vigorous plants We're
able to overcome the attack and will
probably produce an almost normal
yield; the yield of the others will be
greatly diminished or altogether lost.
For the most part this stem rot was
caused by the fungus which produces
the tiny brownish- black pimples or
scabs on the tubers, mistaken by man,
| farmers for particles of soil clinging
to the potatoes.
Treatment of Seed Potatoes for Pre-
vention of scab Should Never
Be Neglected
This fungus is named Rhizoctonia.
The showery weather of June seems
to have been particularly favorable
for the development Of this fungus,
which has caused really serious loss.
Unfortunately this disease is very
wide spread. 1t is found in every po-
tato district of the United States, but
the climate and soil of the intcrmOun-
tain states appears to favor it's devel-
opment exceptionally. There is evil
dence to show that the treatment rec
commended for common scab will
check considerably tho development
of Rhizoctonia. Therefore this treat
ment, either by soaking or fumigation,
should become as well established as
the similar one for the prevention OF
smut among cereals.
Fungus Diseases May Survive il
Manure
These fungus diseases also infect
the soil and are able to survive there
for three or four years. Furthermore,
the germs are able to pass uninjured
through the intCstines of stock fed
upon potatoes infected with these dis
eases. Thus the diseases may be
spread broadcast in the manure from
those animals.
The "BIack-Leg'' Disease
In some instances the stems and
roots of potato vines were blackencd
from the cutting upwards, while the
leaves of such plants were yellow and
curled upwards. In these instances it
is prODaD!c tnaC TIC disease was one
known as "black-leg." No treatment
is known which will check or cure
these stem rots, because the affected
portions ere underground.
Pull Out and Burn All Diseased Vines
1t is advised that at this time the
potato grower &C carefully over his
fields and dig out all vines seen to be
affected with these diseases. They
should then be carried off and burned.
If the farmer is unable to do this with
his entire crop, he should rogue
that portion of it intended for seed
purposes, and this should be his choic-
est plat.
Value Of Careful Seed Selection
Shown
Many striking object lessons were
presented in fields visited during the
earlier part of the present month on
the value of care in seed selection,
also on the bad effect Of planting pO-
tatoes successfully in tho same fields.
Amount Of Disease and Injury on Seed
Potatoes
nccsciOn was takan in cDrinc RI