The Potato Industry oe Colorado. 15 
Loss of Food Value. —The loss in weight is not the only serious 
part of paring away the tuber. As has been shown, the food value 
of the area of the potato just beneath the skin is much greater than 
the center of the potato. Where potatoes are particularly rough 
it will be seen that not only is one-fourth of the weight of the 
potato removed but considerably more than one-fourth of the real 
nutriment of the tuber is lost, and that of the best quality. 
HOW TO DETERMINE GOOD POTATOES ON THE MARKET. 
Color no Guide. —It is not uncommon to hear consumers say 
they always use certain colored potatoes as they have found them 
to be better in quality than some other color. So far as has been 
determined, there is absolutely no correlation between color and 
quality. Certain markets demand a certain colored potato to the 
exclusion of all others simply because they have been educated 
to that color. In fact, if it were desirable to do so, it would be 
possible by breeding to change the color of nearly any of our pota¬ 
toes from white to red or the opposite. 
The Appearance of the Skin indicates the quality of the potato. 
When the skin of a given variety is smooth and more or less trans¬ 
parent with what is called a “baby skin,” and the potato has a 
soft spongy appearance, it is usually deficient in starch and is apt 
to be soggy. This condition is usually the result of immaturity of 
the tuber. The tuber should have a russeted appearance due to 
crackled skin; and it is usually considered a mark of good quality 
when the potato is well covered with lenticels. The degree of rus- 
seting differs with varieties but with a given variety the more 
russeted potatoes are the better in quality.* 
The Amount of Irrigation given to the plants has much to do 
with the quality. It has been found in Colorado that soils that are 
well drained, and particularly those soils which are newly broken 
from prairie or sage brush, usually give better quality than older 
soils that are more retentive of moisture. Where irrigation is 
stopped early to allow the potato to mature in a dry soil the quality 
is greatly improved over those that mature in a wet soil. 
Proper Irrigation a Help to Quality. —The growth of the tuber 
may be controlled under irrigation so as to produce the highest 
*Gilmore of the Cornell Experiment Station found that with most 
potatoes those growing close to the surface were not so good quality as 
those grown deeper in the soil, doubtless because the deep grown tubers 
set first and had a longer season with greater ripeness. It has been found 
also that where plants reached a natural maturity before the vines were 
killed from disease or frost, the tubers were superior in quality to those 
from plants destroyed previous to this condition. 
