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conveyed to another except by actual practice. The grades vary in different markets to suit the supply and demand at each particular market. The classes and grades recognized by the Board of Railroad and Warehouse commissioners for the inspection of wheat at Chicago are as follows:

White winter wheat Nos. 1, 2, 3 and 4.
Long red winter wheat Nos. I and 2.
Red winter wheat Nos. 1, 2, 3 and 4.
Hard winter wheat Nos. 1, 2, 3 and 4
Colorado wheat Nos. 1, 2 and 3.
Northern spring wheat Nos. 1 and 2.
Spring wheat Nos. 1, 2, 3 and 4.
White spring wheat Nos. 1, 2, 3 and 4.

Red winter wheat containing a mixture not exceeding five per cent of white winter wheat is classed as red winter wheat. Red winter wheat containing more than five per cent of white wheat is graded according to the quality thereof and classed as white winter wheat. Hard winter wheat corresponds to red winter wheat except that it is of the Turkish variety common throughout the Missouri River Valley. A mixture of Turkish wheat with other varieties of red winter wheat is graded as hard winter wheat. Northern spring wheat must contain at least fifty per cent of hard varieties of spring wheat. A mixture of more than five per cent of white spring wheat in red spring wheat will cause it to be graded white spring wheat. Black sea and Alinty fife wheat are in no case graded higher than No. 2 and rice wheat no higher than No. 4.. Frosted wheat is not graded higher than No. 4 except that the grade of No. 3 may contain as much frosted wheat as is customary to all wheat damaged in another way. Only a small portion of the wheat of any sort grades No. 1. Most of the wheat dealt in grades No. 2 or No. 3. The following are the rules for grading red winter wheat:

« No. I Red Winter Wheat shall be pure Red Winter Wheat of both ligi t and dark colors of the shorter berried varieties, sound, plump and well cleaned.

“ No. 2 Red Winter Wheat shall be Red Winter Wheat of both light and dark colors, sound and reasonably clean.

“No. 3 Red Winter Wheat shall include Red Winter Wheat not clean and plump enough for No. 2, but weighing not less than fifty-four pounds to the measured bushel.

“No. 4 Red Winter Wheat shall include Red Winter Wheat, damp, musty or from any cause so badly damaged as to render it unfit for No. 3."

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192. Antiquity. — The cultivation of wheat is much older than the history of man. Very ancient monuments, much older than the Hebrew Scriptures, show its cultivation already established. The Egyptians and the Greeks attributed its origin to mythical personages. The earliest Lake Dwellers of Western Switzerland cultivated a small-grained variety of wheat as early as the Stone Age. The Chinese grew wheat 2700 B. C., and considered it a direct gift from Heaven. Wheat is one of the species used in their annual ceremony of sowing five kinds of seeds. Chinese scholars believe it to be a native of their country.

193. Original Habitat.—The existence of different names for wheat in the most ancient languages confirms the belief in its great antiquity. It has been asserted that wheat has been found growing wild in Western Asia, but the evidence is not conclusive. . The Euphrates Valley is believed by De Candolle to be the principal habitation of the species in prehistoric times. So far as known, wheat was not grown in America before its discovery by Columbus.

194. Reasons for Culture.--Its ease of cultivation; its adaptation to a climate favorable to the beginning of civilization ; its quick and abundant return; its ease of preparation for use; its abundant supply of nutritious substance; possibly its rapid improvement under cultivation and the fact of its being paniferous, or possessing that special quality which adapts it above any other grain to the making of light bread, were probably some of the reasons which caused primitive man to begin and continue its

cultivation. In addition, its wide adaptation to different soils and climate has made it one of the principal foods of mankind.

Practicums. 195. STUDY OF THE SPIKE OF WHEAT-Request each student to report the collowing, after examining a head of wheat:

1. Number of spikelets in the spike of wheat. 2. Number of flowers in each spikelet. 3. Number of grains in the whole spike. 4. Determine the number and arrange weight of grains occupying first, second,

third and fourth place from rachis. 5. Number of empty glumes in a spikelet. 6. Make a sketch of the beak, shoulder and auricle of the empty glume 7. How does the flowering glume differ from the palea ? 8. How is the spikelet attached to the rachis ? 9. Draw the rachis.

The spikes of wheat should be laid between pieces of moistened blotting paper for several hours before handing the students, in order to toughen the parts.

196. METHOD OF CROSS-FERTILIZATION.-In order to effect cross-fertilization, the anthers must be removed from all the flowers on the spike, before any of them have shed their pollen. This can best be done when or before the anthers are slightly tinged with yellow. The labor may be reduced by removing all but one or two dozen flowers. If spikelets on the middle portion of the spike are left and only the two lower flowers of the spikelet, more uniformity in the maturation of the flowers will be obtained, as well as more uniformity in other particulars. After carefully removing the unbroken anthers, the emasculated spike may be protected by wrapping about it a piece of tissue paper and tying it above and below. One to two days later the flowers will open, which may be told by adjacent uncovered spikes. Pollen may now be brought

In the upper illustration op from the variety chosen for the male parent and depos- "

erator is removing spikelets ited upon the stigmas of the emasculated flowers. The which are not to be crossed. cross-pollinated spike is again covered, and requires no In the lower the flowers are further attention until ripe.

being opened to remove the 19%. TYPES OF Wheat.-To familiarize the stu- anthers (after Hays). dent with species and subspecies of wheat, give each a couple of spikes and stems of each of the eight species and subspecies, and have him identify by the use of the following outline adapted from Hackel:1

Tritium L. Genus. Spikes with rarely aborted spikelets, rachis not articulate in cultivated species; lowest one to four spikelets smaller than the others, awnless,

* True Grasses, pp. 180-183.

asually sterile. Fertile spikelets inflated or ventricose, two- to five-flowered, fruits one to three. Lowest spikelet closely imbricated; empty glumes broad, one- to many-awned, sometimes a toothed apex; flowering glumes rounded on the back often navicular, many-nerved, ending in one to several awns; fruit slightly compressed laterally, deeply sulcate, hairy at the apex, free. Embryo with epiblast and three rootlets. Annual. Two poorly defined sections of which one (Ægilops L.) is not cultivated. Section II. Sitopyros. Empty glumes sharply keeled. Species three. A. Terminal spikelet usually aborted; mature palea falling into the

parts; lateral teeth of empty glume acute. I. Tr. monococcum. B. Terminal spikelets developed; palea entire; lateral teeth of empty

glume obtuse.
a Empty glumes chartaceous, shorter than flowering glume; palea
as long as flowering glume.

2. Tr. sativum. & Empty glumes sometimes longer than flowering glume, charta

ceous, lanceolate; palea of lowest flower half as long as ite glume.

3. Tr. polonicum. 1. Tr. monococcum L. Spikes compact, articulate, joints separating,

spikelets one-awned, usually only lower flowers maturing fruit. & Tr. sativum Lam. Three races.

I Rachis articulate at maturity; grain entirely enclosed by glumes,

not falling out when threshed.
I*. Spikes loose, almost four-sided when seen from above;

empty glumes broadly truncate in front, with very short,

obtuse middle tooth; obtusely keeled. a. Tr. sat. spelta. 3* Spikes dense, laterally compressed; empty glumes tapering; middle teeth acute; sharply keeled.

b. Tr. sat. dicoccum. II. Rachis not articulate at maturity; fruiting glumes somewhat open; grain falls out easily.

C. Tr. sat. tenax a. Tr. sat. spelta Hackel. Awned or awnless, hairy or smooth

spiked; white, gray, blue, reddish. b Tr. sat. dicoccum Hackel. Always awned. Spikes broader on

two-ranked side, narrower on imbricated side. c Tr. sat. tenax Hackel. Four poorly characterized subraces. 1. Empty glumes distinctly keeled in the upper half, rounded or

only slightly keeled below.
• Spikes long, more or less loose, somewhat dorsally compressed.

1' Tr. sat. vulgare.
• Spikes short, dense, distinctly four-sided.

I! Tr. sat. compactum.
2. Empty glumes sharply keeled at the base.
• Fruit short, thick, not compressed, broadly truncate above.

Jun Tv, sat. turgidum.

3.

** Fruit oblong, narrow, laterally cɔmpressed, somewhat acuminate.

IlIII Tr. sat. durum.
Tr. Polonicum L. A very striking species, with large, compressed,

mostly blue-green spikes. Spikelets appearing as if cut off trans-
versely, because the third and fourth flowers scarcely reach to the
point of the two lower ones; flowering glumes compressed, navicu-
lar, many-nerved, awned; fruit 8-12 mm. long.

METHOD OF DESCRIBING WHEAT VARIETIES. 198. HALF GROWN PLANT IN THE FIELD. Each student should be given a printed or typewritten sheet as indicated below and requested to describe two or inore varieties of wheat growing in the field by underscoring the adjective which inost nearly applies to the condition found.

1. Color: light green; medium green; dark green; light yellowish green; inedium yellowish green; dark yellowish green; light gray green; medium gray green; dark gray green.

2. Leaf blade: average length of ten blades
3. Leaf blade: average width of maximum dimensions of ten blades -
4. Leaf blade: erect; ascending; drooping.
5. Leaf blade: smooth; rough; downy.
6. Leaf blade: veins prominent; veins not prominent.
7. Leaf blade: end tapering; end wit. :les parallel.
8. Leaf sheath: green ; green shading t p ple.
9. Ligule: 2.5 mm. long; 2 mm. long . mil. long.
10. Ligule: white; purple.
II. Auricles: white; green; white with purple tips; purple.
12. Auricles: hairy; partly hairy; smooth.

NOTE: The above practicum and those following are intended to teach a method of describing wheat varieties as first proposed by Cobb and published by Scofield The student should be referred to The Description of Wheat Varieties, by Carl S. Scofield. U. S. Dept. of Agr., Bu. of Pl. Ind. Bul. 47

199. MATURE PLANT IN THE FIELD. Each student should be given a printed or typewritten sheet as indicated below and requested to describe two or more varieties of wheat growing in the field by underscoring the adjective which most nearly applies to the condition found. 1. Height: average of ten culms to tip of apical gloom, not counting awn

if any 2. Vigor of plant: strong; medium; weak. 3. Diameter below spike: average of ten cuims 4. Depth of furrows below spike: furrowed; medium; smooth. 5. Upper part of culm: solid; semi-solid ; hollow. 6. Wall of culm: thick; medium; thin. 7. Color of culm: light yellow; yellow; purple; bronze. & Foliage: scanty; medium abundant.

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