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constitute a cut in points. Measure the circumference at one-third the distance from the butt to the tip of the ear.
10. (a) FURROWS BETWEEN Rows, 5 Points. — The furrows between the rows of grains should be of sufficient size to permit the maize to dry out readily, but not so large as to lose in proportion of grain to cɔb.
(b) SPACE BETWEEN TIPS of GRAINS AT COB, 5 POINTS.—This is objectionable, as it indicates immaturity, weak constitution and poor feeding value.
II. PROPORTION OF GRAIN TO COB, 10 Points.—The proportion of grain is determined by weight. Depth of grains, size of cob, maturity furrows and space at cob, all affect the proportion. In determining the proportion of grain to cob, weigh and shell every alternate ear in the exhibit. Weigh the grain and subtract from weight of ears, giving weight of grain; divide the weight of grain by the total weight of ears, which will give the per cent of grain. Per cent of grain should be from 86 to 87. For each per cent short of standard, a cut of one and one-half points should be made.
375. DETERMINATION OF COMMERCIAL GRADES OF MAIZE. - Give each student two to four pounds of maize of two or more unlike samples and have him determine the proper grade. (367) (a) Per cent of water: grind a sufficient amount of maize into a coarse meal and
determine per cent of water in thirty grams by drying to constant weight at
102° C. (b) Color: determine percentage of color in 500 grains by count. (c) Damaged grains: determine percentage of rotten, moldy or otherwise un
sound grains in 500 grains by count. (d) Broken grains and dirt: determine on the basis of weights the percentage of all
broken grains, meal, dirt, chaff and other foreign material in two or more pounds. 376. COLLATERAL READING. Natural Distribution of Roots in Field Soils. By F. H. King. Ninth Ann. Rpt.
of the Wis. Agr. Expt. Sta. (1892), pp. 112-120. Varieties of Corn. By E. L. Sturtevant. U. S. Dept. of Agr., Office of Expt.
Sta. Bul. 57. Manual of Corn Judging. By A. D. Shamel. New York: Orange Judd Com
pany (1903). Xenia, or the Immediate Effect of Pollen in Maize. By H. J. Webber. U. S.
Dept. of Agr., Div. Veg. Phys. and Path. Bul. 22 (1900). Methods of Corn Breeding. By C. G. Hopkins. Ill. Agr. Expt. Sta. Bul. 82 (1902). Selecting and Preparing Seed Corn. By P. G. Holden. Iowa Agr. Expt. Sta. Bul.
77 (1904). The Maintenance of Fertility. By Charles E. Thorne. Ohio Agr. Expt. Sta. Bul.
110 (1899). Ten Years of Experiments in Corn Culture. By R. J. Redding. Ga. Agr. Expt.
Sta. Bul. 46 (1899), pp. 73-75. Modern Silage Methods. The Silver Manufacturing Co., Salem, Ohio. Maize. Origin of Cultivated Plants. By Alphonse De Candolle. New York:
D. Appleton & Co. (1902), pp. 387-397.
I. STRUCTURE. 377. Relationships.—The tribe (Avenae) to which the oat (Avena sativa L.) belongs differs from the tribe (Hordeae) to which wheat, rye and barley belong, in having the inflorescence in panicles instead of in spikes, and in having a crooked awn on the back of the flowering glume, instead of a straight awn at the end. To this tribe belong few economic plants. Arrhenatherum avenaceum Beauv. is somewhat extensively cultivated in France under the name of Ray Grass. It is only sparingly cultivated in America under the name of Tall Oat Grass. Velvet
Grass (Holcus lanatus L.) is also occasionally sown as a pasture grass.
378. The Plant.—The habit of growth of the roots is similar to that of wheat. The culms are somewhat larger in diameter and of rather softer tissue. Environ
ment has a greater influence upon Nodes of oats: A. exterior view: B. cross. length of culm of oats than of
section of straight culm; C, cross-section winter wheat and rye. Height of showing that a culm after it has fallen
er culm varies from two to five feet; side of the sheath node, not the culm probably the average height is node.
three and a half feet. The leaves are more abundant, the blade broader, and the ligule more pronounced than in wheat.
The Ohio Station found during seven years an average of one
becomes erect by the growth on its lower
pound of grain to two and one-tenth pounds of straw when fertilizers were used, and one of grain to two of straw when no fertilizers were used. The Illinois Station has found as high as two and seven-tenths pounds of straw per each pound of grain, and as low as one and two-tenths pounds in different seasons under otherwise like conditions. Kansas Station found a variation of from four and one-tenth to one and two-tenths pounds of straw to one pound of grain due to season. In general, the more favorable the season the more fertile the soil, and the later the variety or the later the seeding the greater is the proportion of straw to grain.
379. Inflorescence.—A typical panicle is nine to twelve inches long, contains from three to five whorls of branches and bears about seventy-five spikelets. The branches arise from alternate sides of the rachis and vary in length and position; thus the panicle may be open or closed; symmetrical or one-sided. Each spikelet is at the end of a flexible pedicel of variable length. The spikelet contains two or more flowers; only two usually mature, the lower one always developing into the larger grain. The outer glumes are membraneous and
A spikelet of oats: 1, outer considerably larger (three-fourths to one
glumes; 2, lower flower; inch) than the flowering glume. The color 3, upper flower ; 4, rudi
ment of third flower of the latter varies from yellow to reddish brown and black. The flowering glume of the lower flower usually partially encloses that of the upper flower. The awn, when it occurs, is on the back (not at the tip) of the flowering glume, and usually occurs only in the lower flower of the spikelet. The palea is smaller than the flowering glume and enclosed
1 Ohio Rpt. 1896, p. 142.
within the latter. The organs of reproduction are quite similar to those in wheat. (56)
380. The Grain.—The oat kernel, except in hull-less varieties, remains enclosed in the flowering glume and palea. These
parts are usually referred to as the oat hull, but
381. Relation of Hull to Kernel.— The quality of oats depends principally upon the proportion
of hull to kernel. The per cent of hull depends portion of oat ker- both upon the variety and upon the conditions nel: Bo pericarpi of growth, varying from at least twenty to fortyrow of aleurone five per cent. American varieties contain on an
do- average about thirty per cent of hull and seventy sperm with compound starch per cent of kernel. It has been demonstrated
that there is no necessary relation between not shown in this section. (After weight per bushel or shape of grain and the per
ammel.) cent of kernel or food value. The Illinois Station, working during five years with from thirty to sixty varieties, the seed of which was from various sources, but the crops all grown under like conditions, found that generally varieties with long, slender, comparatively light grains had the largest per cent of kernel. The Ohio Station, working with seventy varieties
1 U. S. Dept. of Agr., Div. of Chem. Bul. 9. 2 Ill. Buls. 7, 12, 19 and 23.
Magnified section of
t, testa; a, double
one season, found that the Welcome or short, plump grain group (385) contained a higher percentage of kernel than the Seizure group, which has longer and more slender grains. While in the Welcome group the varieties with the highest weight per bushel contained the highest per cent of kernel, the reverse was the case with the Seizure group. Saunders believes that the results at Ottawa prove that with a given variety the actual weight of hull per grain is the same without reference to the weight per bushel.
Since the hull (flowering glume and palea) develops long before the kernel, it would seem that with a given variety any unfavorable environment which prevents the grain from filling fully would both decrease the per cent of kernel and the weight per bushel. If, however, a large number of varieties are grown under the same conditions, it is probable that those varieties best suited to the environment would develop their kernels most completely and thus have the highest per cent of kernel. Thus the per cent of kernel might in some instances be the highest in varieties with short, plump grains, and in other instances in those with long, slender ones, depending upon their adaptability to the given region or season.
382. Weight per Bushel.—The legal weight per bushel in all States of the United States is thirty-two pounds, except in Idaho (thirty-six), Maine, New Jersey, Virginia (each thirty) and Maryland (twenty-six). In Canada it is thirty-four pounds. Oats may vary in weight from twenty-five to fifty pounds per bushel, the lighter weight being found in the more southern climates. Richardson found the average weight per bushel of 166 varieties gathere 1 from various sections of the United States to be thirtyseven pounds. In order to increase the weight per bushel and consequently the commercial quality, elevators frequently resort to a process known as clipping. i i Ohio Bul. 57, p. 108.
3 Can. Farms Rpt. 1903, p. 8.