495. Center of Production.—In 1850 the concentration of the rye crop in the North Atlantic division was greater than that of barley, eighty-three per cent of the entire crop coming from that region. The westward movement has not been so rapid as in the case of barley; the North Atlantic division furnished twenty-nine and the North Central division sixtythree per cent of the total production in 1900. The center of production in 1850 was somewhere west of the center of New York and Pennsylvania; in 1899 it had shifted westward into the State of Illinois. Fifty-three per cent of the crop of 1899 was furnished by four States: Wisconsin, Pennsylvania, New York and Michigan.

496. Yield per Acre.-The average annual yield per acre of rye during the decade 1893-1902 was approximately fifteen bushels, an increase of about three bushels over the previous decade. There is little variation in yield in the North Central and North Atlantic States; the South Atlantic States fall quite below the average. Twenty to twenty-five bushels per acre is considered a good yield. The legal weight per bushel is fiftysix pounds in Canada and all the States of the Union, except California, where it is fifty-four pounds.

497. Commercial Grades. Only one class of rye is recognized, the following being the rules for grading this class by the Illinois Board of Railroad and Warehouse Commissioners:

"No. 1 rye.-Shall be sound, plump and well cleaned.

"No. 2 rye.-Shall be sound, reasonably clean and reasonably free from other grain.

"No. 3 rye.-Shall be reasonably sound, reasonably dry, free from must, and not good enough for No. 2.

“No. 4 rye.—All rye, damp, musty, or for any other cause unfit for No. 3."

498. History. The cultivation of rye is not nearly so ancient as that of wheat and barley. It was unknown to the ancient Egyptians. The ancient Greeks did not know it. Its introduction into the Roman Empire was hardly earlier than the

Christian era. The origin of its cultivation is supposed to be northeastern Europe.

Within modern times rye was formerly a more important crop. Even as late as the middle of the nineteenth century rye was said to have formed the principal sustenance of at least one-third the population of Europe, barley taking its place in countries nearer the Mediterranean. It was annually sown with wheat, and is yet to a large extent mixed with wheat in grinding, and the resulting flour is called meslin. The mixture of maize and rye for bread was common in New England. Relatively, rye was formerly much more important in England and the United States.

Practicums.

- Make up

499. INFLUENCE OF SPECIFIC GRAVITY UPON GERMINATION. three solutions of sodium nitrate with a specific gravity of 1.20, 1.26 and 1.32, using a hydrometer to determine the specific gravity. Solutions may be placed in oatmeal dishes. Take preferably a sample of rye of rather low grade and divide into small, medium and large sized grains, either by hand or by means of sieves. (433) Then divide each sample into four groups according to specific gravity, by placing the sample in the solution of highest specific gravity; then put that which floats in the solution of next highest specific gravity, and so on. Grains can be conveniently removed from the solution by using a piece of wire gauze. Place fifty seeds of each of the twelve groups thus obtained in germinator at 70° F. and determine the number germinating in 24 hours .; 48 hours .; 72 hours . . .: 96 hours .; 120 hours (475) Seeds may also be grown as in (433). Wheat and barley may also be treated in the same solutions, and many other agricultural seeds may be tested by varying the density of the solutions. A saturated solution of common salt and a saturated solution of ammonium nitrate made by boiling will upon cooling to 75° F. have a specific gravity of approximately 1.20 and 1.30 respectively. For further details, see N. Y. (Geneva) Bul. 256.

500. STUDY OF PLANT.-Examination under Nos. 1 to 8 preferably made in field: Nos. 9 to 16, in the laboratory.

1. Height of culm: average of ten culms to tip of upper beard 2. Diameter below spike: average of ten culms

3. Wall of culm (compared with wheat): thick; medium; thin.
4 Foliage (compared with wheat): scanty; medium; abundant.
5. Rust: leaves, per cent
6. Ergot: per cent
7. Spike: erect; leaning; nodding.

; culms, per cent

8. Length of spike: average of ten spikes from lower joint of rachis to tip of upper outer glume

9. Number of grains per spikelet

IO.

Number of grains per spike: average of ten spikes 11. Weight: one hundred grains

ten grains

13. Plumpness: plump; medium; shrunken.

14. Weight per bushel: obtained by weighing one pint.

15. Draw outer glume of rye and wheat.

16. Draw flowering glume of rye and wheat, using bearded glumes.

XXIV.

RICE.

I. STRUCTURE AND VARIETIES.

501. Relationships.-Rice (Oryza sativa L.) belongs to the tribe Oryzeae. In some respects it is rather more closely related to maize and sorghum than to the other cereals. There are a number of species of the genus Oryza growing wild in the tropics of both hemispheres. To this tribe also belongs wild rice (Zizania aquatica L.), sometimes called Canada rice and sometimes referred to as "the reeds," the fruit furnishing food for the reed birds or bobolinks. The wild rice plant is ar annual, grows usually from five to eight feet in length above water, and bears a cylindrical panicle one to two feet long. The flowering glume is bearded and encloses a slender cylindrical kernel varying in length from a half to almost an inch, and is of dark slate color when ripe. It grows somewhat extensively in marshy places throughout North America, as well as northeastern Asia, particularly around the region of the Great Lakes, where the Indians collected it in large quantities for food and even sowed it rather extensively. Wild rice furnishes a nutritious and an acceptable food. Although prolific, the tendency to shatter its seed upon ripening will probably prevent its general cultivation.1

Another species of wild rice (Zizania miliacea Mx.) is common in the Southern States, especially in the bayous of Louisiana. No use is made of the seeds, but it is said that two crops of good hay may be cut from it annually.

1 For further account of wild rice see The Wild Rice Gatherers of the Upper Lakes. By Albert Ernest Tenks; extract from the 19th Ann. Rpt. of the Bureau of American Ethnology.

502.

The Plant. The culms of the rice plant vary in length from two to six feet, usually from four to five feet, depending

upon soil, water and methods of culture. The Louisiana Station has found the straw as ordinarily harvested to vary from 1.6 to 2.3 pounds for each pound of rough rice.1 Like the other so-called small grains, rice tillers freely; one seed sending up many culms when conditions are favorable. The spikelets are oneflowered, arranged on short pedicels so as to make a compact panicle in appearance somewhat intermediate between oats and barley. The outer glumes consist of two small scales or bristles, underneath which are two more minute rudimentary ones. flowering glume is frequently awned. The flower of rice differs from all other cereals, having six stamens instead of three.

The

503. The Grain. The fruit or caryopsis of rice is enveloped in the flowering glume and palea, which remain attached when threshed. When in this condition, rice is known as paddy. The flowering glume and palea are usually referred to as the husk or hulls, while the pericarp, testa and nucellus corresponding to the bran of wheat are referred to as the cuticle. The surface of the rice kernel is marked with four longitudinal depressions which give it a fluted appearance. The embryo is not embedded in the kernel but is so exposed that it is easily rubbed off in the process of milling. The cells of the aleurone layer are relatively small in one to two rows. Evidently these cells are removed by the polishing process. (526) The endo1 La. Bul. 61, 2nd. ser., p. 392.