The: Potato Industry or Colorado. • 25 
by cool storage, excessive spring sprouting may be prevented by 
greening. This is done by exposing the tubers to the light. The 
thinner the potatoes are spread out (certainly not over one foot 
deep) the better, and the oftener they are shoveled over, the better, 
which should be once a week, at least, for the last month. Of 
course it must be understood that the tubers are not cut previous 
to this treatment and are not exposed to heat and drying. Green¬ 
ing not only toughens the tissues and produces chlorophyll in the 
bark or skin, but largely destroys the spores of fungus diseases, 
and makes the seed pieces less liable to rot. For Colorado condi¬ 
tions, greening is preferable to treatment with corrosive sublimate 
or formalin, which treatments we do not recommend. 
Treatment for Scab* —For four seasons, experiments have 
been made both at the Experiment Station and with growers in 
the Greeley district, with a treatment of seed for scab. In this 
treatment the seed was soaked two hours before being cut for 
planting in a solution of a pound of formalin to fifteen gallons of 
water. No beneficial results whatever were secured. 
Cutting Seed. —In planting potatoes it should be remembered 
that we are not planting the seed but a cutting of the old plant. 
The question of the size of the cut piece is always before us. The 
bud with a very small piece of tissue may be taken from the tuber 
and made to produce a plant. It has been found, however, in 
various experiments that the yield of tubers increases with the size 
of the seed piece, up to a certain limit. The reason for this is that 
the new plant must start its growth from the stored plant food in 
the piece of potato until it has sufficient root system to take care 
of itself. If the seed piece is too small or becomes dried there is 
not sufficient plant food to push it along so as to make a vigorous 
plant: conversely, if there is more plant food in the piece than is 
essential for growing the plant the excess is wasted. It has been 
proven in numberless careful experiments that it pays to use pieces 
as large as two ounces.f 
Two-Ounce Potatoes may be planted without cutting. Four 
ounce potatoes are best cut in two. In order to have the eyes 
strong light could reach them. These tubers were somewhat shriveled 
from being stored in a cellar where the temperature was higher than 
was desirable and where the air was too dry. Nearly all became green 
and many lost so much moisture as to be decidedly dry and toughened. 
At planting time the potatoes had started to grow but the sprouts were 
only from a quarter to a half inch in length and were green and tough 
enough to withstand handling. It was thought that the worst of these 
tubers were too badly dried out to germinate, so they were planted by 
themselves, but, to our surprise, nearly all produced healthy plants. 
*See Potato Diseases in this bulletin. 
tSee in this bulletin the subject of Stands 
