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367. Grade Uniformity.—Scofield" has pointed out that the essential elements in grading maize are: (1) the moisture, (2) the percentage of colors in mixtures, (3) the percentage of damaged grains, and (4) the percentage of broken grains and dirt. He proposes to put all dent maize into three classes as follows:

1. Yellow maize; at least 95 per cent yellow.
2. White maize; at least 98 per cent white.
3. Mixed maize; all maize not included above.

The maximum limits for each grade of yellow maize are suggested in the following table:

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II. HISTORY. 368. Nativity.-The records of the early voyagers prove that maize was cultivated on the American continent from Maine to Chile at the time of its discovery. It was then the great bread plant of the New World. Numerous varieties of maize have been found in the ancient tombs of Mexico, Peru and New Mexico. These monuments are supposed to be two thousand years old. As there were many varieties at this time, the cultivation of maize must have been considerably more ancient, although not necessarily so ancient as that of wheat. There was a semi-civilized race of people in Peru, Mexico, and even in New Mexico, who made considerable use of maize, using it boiled and roasted when green, and grinding it and making it into bread when ripe.

1 U.S. Dept. Agr., Bu. Pl. Ind. Bul. 41.

369. Talue to Colonists.—Maize was the salvation of many of the early colonies, preventing the colonists and their stock from starving. The tame grasses had not been introduced, so that besides maize stover their stock had nothing but salt marsh hay.

The early settlers learned the cultivation of maize from the Indians. The James River settlers, under the tuition of the Indians, began to raise maize in 1608, and within three years they appeared to have as many as thirty acres under cultivation. The Pilgrims found it in cultivation by the Indians on their arrival at Plymouth, and began its cultivation in 1621, manuring, as the Indians did, with fish.

“According to the manner of the Indians we manured our ground with herrings, or rather shads, which we have in great abundance and take with ease at our doors.

“You may see in one township a hundred acres together set with these fish, every acre taking a thousand of them, and an acre thus dressed will produce and yield as much corn as three acres without fish.” In the Jamestown settlement they planted pumpkins and melons in the hill with the maize.

370. Introduction into Eastern Continent. — Maize is pretty certainly of American origin. It has been introduced into Europe, Asia and Africa since the discovery of America. After its introduction into the old continent it spread very rapidly across northern Africa and southern Europe and across Asia into China. The rapidity with which it spread gave rise to disputes as to its origin and considerable confusion as to its name.

Maize has been known by the following curious names in Europe: Turkish corn, Italian corn, Roman wheat, Sicilian wheat, Indian wheat, Spanish wheat, Barbary wheat, Guinea and Egyptian wheat. These names were given it in various places on account of the country in which it was supposed to have originated. They simply indicate the country from which and through which maize was introduced. The names, with the exception of Indian, are those of places bordering on the Mediterranean Sea. This would seem to indicate that maize

was brought from America in vessels which sailed into the Mediterranean Sea and landed in the various countries denoted. The climate on both sides of the Mediterranean is fairly well adapted to the growth of maize. The rapid introduction into these countries of so striking a plant and its spread therefrom is not a matter of surprise.

Practicums.

371. DESCRIPTION OF MAIZE PLANT. Name of variety .... Date .... 1. Maturity of plant silking: roasting ear; partly dented or glazed ; dented

2. Height of plant: average of ten plants ... feet ... inches 3. Proportion of ears: number of ears on one hundred stalks ... 4. Barren stalks : number in one hundred stalks ... 5. Position of ear: pointing upward; horizontal; pointing downward. 6. Husks: adherent; medium; non-adherent. 7. Husks: abundant; medium; scanty. 8. Length of shank: distance from node to base of ear, - average of ten

plants ... 9. Circumference of stem: at middle of internode between second and third node

from ground .. . 10. Circumference of stem: at middle of internode below main ear ...

12. Average width of leaf blades : average of five plants
13. Average length of leaf blades : average of five plants...
14. Length of tassel: average of ten plants . ..

372. THE CHARACTERS OF THE GRAIN.–Give each student twenty-five to thirty grains each of five types of maize or five varieties of a single type. For Nos. 12 to 18, a number of grains should be soaked in hot water for thirty minutes, or in cold water for twenty-four hours. For taking measurements, furnish each student with a sheet of cross-section paper. Name of variety .... Date ....

1. Weight: ten average grains in duplicate (a) ... (b) ... 2. Length: ten average grains in duplicate (a) ... (b) ... 3. Width: ten average grains in duplicate (a) ... (b) ... 4. Thickness: ten average grains in duplicate (a) ... (b) .. . 5. Ratio of width to length : divide length of ten grains by width of ten grains

(a) . .. (b) . ... 6. Ratio of thickness to width: divide width of ten grains by thickness of ten

grains (a) ... (b) ... 7. Shape; flat; spheroidal; conical.

8. Shape (side view): cuneate wedge-shape; rounded-cuneate; truncate-cuneate;

shoe-peg form; rectangular; rounded corners. 9. Summit: rostrate; mucronate; rounded; flat; dented. 10. When dented: dimple; long dimple; creased; pinched ; ligulate. II. Color: white; yellow; golden ; red; purple. 12. Place of color: endosperm; aleurone layer; hull. 13. Character of endosperm: corneous; partly corneous; farinaceous; glucose. 14. Proportion of corneous endosperm, if dent variety: large; medium; small. 15. Size of embryo: large; medium; small. 16. Sketch of cross-section: show arrangement to scale of embryo, glossy and white

endosperm. 17. Sketch of transverse section: show arrangement to scale of embryo, glossy and

white endosperm. 18. Sketch of lateral section: show arrangement to scale of embryo, glossy and

white endosperm. 373. The CHARACTERS OF THE EAR.-Give each student two or more ears of each of the five types of maize, or five different varieties of the same type. Ten ears of a given type or variety are none too many for a thorough study, but with larger classes it may be necessary to economize in material. Ears properly labeled, showing characters mentioned below, should be displayed for guidance of stu: dents. (220) Name of variety .... Date .... 1. Color of grain : white; yellow; golden ; red; purple. 2. Color of cob: white; light red; deep red. 3. Surface: smooth; medium; rough; very rough. 4. Sulci: absent; apparent; narrow; distinct; very distinct. 5. Pairs of rows: distichous; not distichous. 6. Number of rows : one-fourth length from butt ...; from tip ... 7. Direction of rows: rectilinear; spiral to right; spiral to left; irregular. 8. Grains: very loose; loose; firm; mosaic-like.

Grains: upright; sloping; imbricated. 10. Ear: cylindrical; cylindraceous; slowly tapering; tapering; distinctly taper

ing; flat.

Butt: even ; shallow rounded; moderately rounded; deeply rounded. 12. Butt: depressed; compressed; depressed-rounded; depressed-compressed :

enlarged; expanded; open. 13. Tip: sides of cob exposed; end exposed; end covered; terminal grain. 14. Juncture of ear stalk: large; medium; small. 15. Length of ear (extreme length): (a) ... (b) ... 16. Circumference of ear one-third distance from butt: (a) ... (b) ... 17. Weight of ear: (a) ... (b) .... 18. Weight of cob: (a) ... (b) . . 19. Percentage of grain : (a) ... (b) ... 20. Circumference of cob one-third distance from butt: (a) ... (b) ... 21. Ratio of circumference of cob to circumference of ear: (a) ... (b) ...

374. SCORE CARD FOR DENT MAIZE. I
Furnish each student with a sample consisting of ten ears of maize.

1. TRUENESS TO TYPE OR BREED CHARACTERISTICS, 10 POINTS—The ten ears in the sample should possess similar or like characteristics, and should be true to the variety which they represent.

2. SHAPE OF EAR, 10 POINTS.—The shape of the ear should conform to the variety type. Ear should be full and strong in central portion and not taper too rapidly toward the tip.

3. PURITY (a) IN GRAIN, 5 POINTS.-Color of grain should be true to variety and free from mixture. For one or two mixed grains, a cut of one-fourth point; for four or more mixed grains, a cut of one-half point should be made. Difference in shade of color must be scored according to variety characteristics.

(b) IN COB, 5 POINTS.-An ear with white cob in yellow maize or red cob in white maize, should be disqualified or marked zero. This mixture reduces the value of the maize for seed purposes, indicates lack of purity, and tends towards a too wide variation in time of maturity, size and shape of grains.

4. VITALITY OR SEED CONDITION, 10 POINTS.—Maize should be in good seed condition, being capable of producing strong, vigorous growth and yield.

5. TIPS, 5 POINTS.— The form of tip should be regular; grains near tip should be of regular shape and size. The proportion of tip covered or filled must be considered. Long pointed tips as well as short flattened or double tips are objectionable.

6. BUTTS, 5 POINTS.— The rows of grains should extend in regular order over the butt, leaving a deep depression when the shank is removed. Open and swelled butts, depressed and flat butts, with flattened glazed grains, are objectionable and must be cut according to the judgment of the scorer.

7. GRAINS (a) UNIFORMITY OF, 10 POINTS; (b) SHAPE OF, 5 POINTS.- The grains should be uniform in shape and size, making it possible to secure uniformity in dropping with the planter, and consequently a good stand. The grains should also be not only uniform on individual ear, but uniform in color and true to variety type. The grains should be so shaped that their edges touch from tip to crown.

8. LENGTH OF EAR, 10 POINTS-The length of ear varies according to variety, type, and the characteristics sought for by individual breeders. Uniformity in length is to be sought for in a sample, and a sample having an even length of ears should score higher than one that varies, even if it be within the limits. Instructor will set limits for length of ears of sample according to variety, allowing a variation of one inch. The sum of the excesses and deficiencies in inches shall constitute a cut in points.

9. CIRCUMFERENCE OF EAR, 5 POINTS.—The circumference of the ear will vary according to the variety and the latitude. The circumference of the ear should be in symmetry with its length. An ear too great in circumference for its length is generally slow in maturing, and too frequently results in soft maize. Instructor will set limits for circumference of ears of sample according to variety, allowing a variation of one-half inch. The sum of the excesses and deficiencies in inches shall

1 The score card of the Iowa State College slightly modified. Iowa Bul. 77 (1904).

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