12 The Colorado Experiment Station. 
Corn, Tobacco and Tomatoes have remained to a great degree 
American crops, the tomato having been the last to enter use on a 
commercial scale, and that almost entirely in America. Cotton 
came to us and we lead the world in its production. It has been 
the reverse with the potato. South America, its home, produces 
less in total than Colorado, and the potato crop of the United States 
is insignificant as compared with that of Europe. 
The Potato as Freight is important, because it is better economy 
to grow it in the north, or in the high altitude districts, and trans¬ 
port it south, than to grow it in the uncongenial climate of the 
south. The weight of the potato crop of the world is nearly half 
more than the leading grains—wheat or corn—and nearly three 
times the weight of the world’s rice crop. The average crop, in 
tons per acre, of potatos in Colorado, is about six times that of 
grain. Fully as large a per cent, of the potato crop is shipped by 
rail as of wheat or corn, and potatoes pay a higher freight rate. 
quality in potatoes. 
Table Quality in potatoes is an important factor in the de¬ 
velopment of the industry in the United States. All but a very 
small per cent, of the potatoes grown in this country are used for 
human food. When the quality is high the amount consumed per 
capita is considerably more than in years when the quality is low. 
Attention on the part of the growers to producing smooth, white 
fleshed, mealy tubers will increase the per capita rate of consump¬ 
tion. 
What Constitutes Quality. —From the American standpoint, 
the popularity of the potato as a food depends for the most part 
upon its starch content, because in the United States the consumer 
demands a mealy potato. In continental Europe, France in particu¬ 
lar, a soggy potato is preferred. The amounts of starch and other 
ingredients vary with the variety and also with the conditions under 
which the potatoes grow. C. F. Langworthy in the Yearbook of 
Agriculture gives the average chemical analysis as follows: “The 
edible portion of a potato is 78.3% water, 2.2% protein, .1% fat, 
18.4% carbohydrates (principally starch), 1% ash or mineral 
matter.” 
A Thin Cross Section of a potato held to the light will show 
that the tissue is composed of several different layers or areas. The 
outside skin corresponds to the bark of the stem; inside the bark is 
the sap wood or vascular tissue which in the potato is known as the 
cortical layer. This is readily distinguished as a layer from one- 
eighth to one-half inch thick just under the skin and is bounded by 
a dark line of hbro-vascular tissue. Inside this line is another area 
that is ordinarily of about the same density as the cortical, known 
