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WATER USED PER POUND OF DRY MATTER
Pounds Potatoes . . . 200 to 230 Corn . . . . . . . 270 Tobacco . . . 300 to 370 Soy-beans . . . . . 527 Buckwheat.
Clover . . . . . . 576 Chicory . . . .
Oats . . . . . . . 503 Mustard. . . . Oats . . . . . . . 460
King' has shown that the amount of water required to make one pound of dry matter in the tuber and vine of potatoes varied between 272 pounds and 497 pounds during the years 1892–7, while that for oats ranged between 446 and 595 pounds; barley, 375 to 404 pounds; peas, 477; corn, 223 to 398 pounds; clover (first crop), 370 to 582 pounds; clover (second crop), 730 to 983 pounds.
CONSIDERATIONS OF SEED Source of Seed.—It is often advised that potatoes be obtained from another soil and from a more northern latitude if vigor and delayed maturity are desired, and from a southern latitude if earliness is sought; but, generally speaking, potatoes bred for a district do better there than elsewhere. Few European varieties of potatoes are worth growing in America, and any introduction requires acclimatization and selection. In England we noted that northern grown Scotch seed did not yield so heavily the first year as the second, and the same was true of Maine grown seed in the Hudson River valley. Brooks,' of Massachusetts, and Bishop, of Maryland, report exactly to the contrary, although in a subsequent year Brinkley, at the same station, obtained higher yields from home grown seed. The Rhode Island Station found that varieties which produced large yields gave increasing yields the longer the seed tubers had been home grown, and that those which produced smaller yields gave diminishing yields the longer the seed had been home grown. At Louisiana Station home grown seed was equal to, if not better, than western, or eastern grown or Boston seed. At Georgia Station southern grown seed did best, and the statement is made that the value of seed depends more upon the care exercised in the selection of the strain than the locality where it is grown. Martinet', of France, reports that in several diversified trials seed tubers from higher altitudes gave better yields under all circumstances.
1 Mass. (Hatch) Report, 1896, pp. 25, 26.
?Md. Bul. 17, p. 257.
Bailey’, of Cornell, lodges a criticism against the comparison of northern and southern grown seed. He believes the variations to be due much more to the stock itself-how the plants have been grown and handled in previous years—than to any influence of latitude. He believes it to be impossible to secure stock from different growers which is sufficiently uniform to allow of comparative experimentation. That such variation exists is shown by Brooks's observation on Beauty of Hebron and Early Rose potatoes. Seed potatoes of the same variety obtained from different localities gave a variation in yield of about 50 per cent. for each variety. Probably the matter is one of individuality. It is necessary to study each potato and hill, and perpetuate a variety suited to the particular environment. If this variety possesses the capacity of adapting itself rapidly to other environments it is more useful, but it must be able to grow vigorously and mature its tubers in order to maintain its value. The Ohio Experiment Station* found that the selection and storage of potatoes is of more importance than the use of seed grown on other soil. Kansas Experiment Station found that tubers matured in July were the most satisfactory seed for the second crop, and the practice of using first-crop tubers as seed for the second crop is rapidly gaining ground in the South, owing to the difficulty of holding seed over.
? (N. Y.) Cornell Bul. 25, p. 175.
Management of Potatoes Previous to Planting.–The best way to hold seed potatoes is in cold storage at a temperature of 33° to 35° F. Should the temperature fall to freezing-point (32° F.) for a short
FIG. II-A USEFUL POTATO TRAY FOR THE STORAGE AND
SPROUTING OF SEED POTATOES For small quantities, a useful size is 24 x 12 inches. This size will hold about forty pounds of tubers, and can be conveniently handled. The
larger size holds about eighty pounds of tubers.
time probably no harm will result, as the freezingpoint of potatoes is rather lower than that of water. As most farmers do not have cold storage some substitute must be found. A cool, fairly dry cellar, or a root-house, is a very good alternative, or, failing this, the potatoes may be pitted outside and covered so that no frost can reach them (see “Storing ''). Several weeks before planting the tubers should be spread out on the barn floor two or three thick, in the light, to quicken growth. Potatoes vary in the time they take
to germinate. Mature potatoes will not begin to grow until they have had a period of rest. In some varieties this may be but a few weeks, while others may be held months before they show signs of growth. In the island of Jersey and the early potato growing districts of the United Kingdom it is customary to store the seed potatoes in flat trays (Fig. II). The advantages of these are: (1) the seed cannot heat; (2) a large quantity can be stored in a room, the trays being tiered almost to the roof; (3) seed can be easily examined at any time and conveniently moved, hence diseases—as, wet-rot, dry-rot, etc.—are more easily controlled; (4) the potatoes may be sprouted in the trays; (5) the potatoes can be moved to the field in and planted from the trays.
The tray is the best means of storing new varieties which have been purchased or grown in small quan
Sprouting Potatoes.-Lavalleé' and many others have found that sprouting seed potatoes in a welllighted room increases the yield and earliness, and produces a more vigorous growth of vines and a larger starch content in the tubers. One explanation offered for the increase in yield is that the short, thick stem developed under the above conditions bears many scales or leaves for its hight, and it is from the axils of these scales, the place where the scale joins the stem, that the tuber-bearing branches are produced (Fig. 12). The more scales produced, the more opportunity for the development of tubers. If the tubers start growth in the dark, either indoors or below
1 E. S. R., XII., p. 1032.