332 FIELD AXD GARDEN PRODUCTS 



profitable increase was reached with tubers weighing 4^ and 3 ounces 

 respectively. The size of seed tubers selected becomes a matter of im- 

 portance when they are to be cut, for we have seen that the heavier 

 the cutting the larger the total yield, and seed tubers for cutting 

 should be of such size that their halves, quarters, or other divisions 

 shall not be extremely small. 



Small Potatoes for Planting. Whether or not to use uncut 

 small potatoes for seed is an important question on which farmers 

 are divided. Some present the plausible argument that the use of 

 undersized potatoes results in degeneration. If this claim is based 

 on the results of experience it should determine practice, but if the 

 conclusion is simply a generalization based on the fact that large 

 seed usually give best results the reasoning is defective, and the 

 question remains open. The potato tuber is not a seed, but an un- 

 derground stem, and the relations existing between seeds and their 

 progeny do not necessarily exist between a tuber and its descendants. 

 Others hold that potatoes just below marketable size, if shapely and 

 sufficiently mature, may be used without serious deterioration, and 

 that for economic reasons their use is especially desirable, because if 

 not planted or used at home they must be lost or fed to stock, for 

 which purpose their value is usually smaller than the market price. 



The result of tests at a number of experiment stations have uni- 

 formly indicated that small tubers uncut can be used for seed pur- 

 poses without detriment to the succeeding crop. It may still be 

 urged, however, that the choice of small seed year after year will re- 

 sult in degeneration. On this question the information is meager, 

 but two experiments, extending over four and eight years, respec- 

 tively, have been reported in which no degeneration resulting from 

 the continued use of small potatoes from the preceding crop was ap- 

 parent. Although the eviaence seems fairly conclusive that small 

 uncut seed potatoes may sometimes be used with profit, it cannot be 

 advised that small seed tubers be selected year after year from a crop 

 which has been grown from small potatoes. Potatoes of irregular 

 shape and injured tubers should be rejected as unfit for planting. 



Number of Eyes and Weight per Set. Many potato growers 

 cut tubers into pieces containing one, two, or more eyes, laying 

 greater stress on the number of eyes than on the size of the cutting. 

 Extensive experiments at the Indiana station and elsewhere prove 

 that of the two factors, number of eyes and weight of piece, the lat- 

 ter is the more important. Of course it is desirable that each piece, 

 whether large or small, should contain at least one eye, and it has 

 been generally profitable for it to be of such size as to contain at least 

 several eyes; but whether it has one or many eyes it is important 

 that the seed piece be heavy enough to furnish abundant nutriment 

 to the shoots which spring from it. A single eye may give rise to 

 several stalks, for each eye is a compound bud or cluster'of buds. An 

 eye can be bisected, and each half may then grow successfully if it 

 is not a victim to dryness or decay, to which its exposed condition 

 subjects it. 



In one series of experiments it was found that the number of 



