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question may be required. Definite references to proper bulletins should be fur. nished each student.

203. RELATION of Color, Hardness, Size, Specific Gravity AND CON

TENT OF GLUTEN.

I. Take five varieties of wheat varying as widely as may be in different qualities mentioned, as for example, Fultz, Gold Coin, Rudy, Turkey, Kubanka,

2. Note color and hardness.

3. Find weight of 500 grains.

4. Fill a 50-gram picnometer with benzene and weigh on balance sensitive to I mgm. Add twenty grams of wheat and weigh. Add weight of wheat to weight of picnometer and benzene and subtract last weight, which will give weight of volume of benzene equal to volume of grains of wheat. Divide this difference by the specific gravity of benzene, which will give the weight of a volume of water equal to the volume of grains of wheat. To determine the specific gravity of the wheat, divide twenty grams of wheat by the weight of an equal volume of water. 5. To find the relative size of grains, divide the weight of five hundred grains by their specific gravity.

Snyder's apparatus for determining the granulation of flour, I, Erlenmeyer flask; 2, suction connection; 3, rubber cork; 4, adapter; 5, rubber (tube) packing, making air-tight joint; 6, section of brass crucible overlapping sec

tion 7; between these two parts bolting cloth is placed and removed as desired-any size cloth can be inserted; 8, wire clamp

6. To determine content of gluten, take thirty grams of ground wheat, work with water in a round bottomed glass vessel with spatula, and wash off starch after gluten has gotten into a sticky mass, and continue to wash until there is no appearance of starch grains being carried off. To be sure that all the starch is freed from gluten, test washings with potassium iodide; blue color shows the presence of starch. Work mass of gluten in fingers until all water that will run off has been expelled. Weight will give amount of moist gluten. Place in drying oven at 110° C until constant weight is obtained. Weight will give amount of dry gluten At same time find weight of dry matter in ten grams of ground wheat. Calculate per cent of moist and dry gluten from data obtained.

If there is not time or facilities to carry out No. 6, the instructor may determine the content of gluten in advance and allow the student to compare Nos. 2 to 5 with the results thus obtained.

204. QUALITY OF FLOUR.-Furnish each student with a sample of high grade and low grade flour and have him determine the following:

1. Character of granulations: Note under a high power microscope (172) whether flour particles are round or angular.

2. Size of particles: By means of apparatus deholding apparatus in place. vised by Snyder, determine the amount of flour in twenty-five grams that will pass through bolting cloth Nos. 9 to 20.

3. The color test: Place samples of flour on plate of glass and determine color by means of a series of colored glass slabs.1

4. The baker's sponge test: Place in a wide pint porcelain bowl one hundred grams of flour. Dissolve five grams of sugar and five grams of compressed yeast in sixty-five grams of water and stir with steel spatula into flour. Continue to add water and knead until proper consistency is obtained. Note quantity of water required to give equal consistency in both samples. Place dough in cylinders about four inches in diameter graduated into c. c.'s. Set tube in water at 90° F. and determine time required to rise to full height and maximum volume attained. If time permits, allow second rise to occur and note time and maximum volume. The first rise takes about an hour and a half to two hours and the second rise from an hour to an hour and a half. If the per cent of gluten has been determined (203), calculate volume to each gram of gluten.2

205. COLLATERAL READING.—

The Basis for the Improvement of American Wheats. By Mark Alfred Carleton. U. S. Dept. of Agr., Div. of Veg. Phys. and Path. Bul. 24, pp. 63-83.

The Structure of the Wheat Grain. By Charles E. Bessey. Neb. Bul. 32, pp. 100-114.

William C. Edgar: The Story of a Grain of Wheat, pp. 111-131. New York: D. Appleton & Co.

Plant Breeding. Willet M. Hays. U. S. Dept. of Agr., Div. of Veg. Phys. and Path. Bull. 29, pp. 44-54.

Grain Elevators. By N. A. Cobb, Dept. of Agr., Sidney, New South Wales, Misc. Pub. 452.

1 These can be purchased of Eimer & Amend, New York. For further details see Minn. Bul. 62. (1899), pp. 346-352.

VIII.

MAIZE.

I.

1

STRUCTURE.

206. Name.-Columbus found Zea mays L. cultivated on the Island of Hayti, where it was called mahiz; hence the name maize. Mahiz, or marisi, is said to be an Arawak Indian word of South American origin. The word corn is used in Europe as a generic term for all cereals, and originally the word meant any hard edible seed, grain or kernel. In England an ear of corn means a head or spike of wheat. Naturally, therefore, the colonists, finding maize cultivated abundantly by the Indians, applied the term Indian corn to distinguish it from other corn. In the United States corn is everywhere understood to mean maize and a Pennyslvania court has ruled that the word corn is a sufficient description of Indian corn. In Latin America "maiz" is the term generally used.

207. Fodder, Stover and Silage.-Fodder, when applied to maize, is the plant, including the ears, which has been cut and field cured without regard to the manner or thickness of planting or stage of maturity. Stover is the residue after the ears have been removed from the fodder. When the whole plant or the residue after removing the ears is placed without curing in the silo, the resulting material is called silage.

208. Relationships.-The tribe (Maydeae) to which maize (Zea mays L.) belongs differs quite widely from the tribe (Hordeae) to which wheat, rye and barley belong. In the same tribe with maize belong teosinte (Euchlaena mexicana Schrad.), a sub-tropical plant sometimes cultivated in the Southern States

1 Harshberger, J. W.: Maize; A Botanical and Economic Study, p. 88.

for fodder purposes, and gama grass (Tripsacum dactyloides L.) which was a rather conspicuous feature of the native herbage of the prairie regions in the central and southern

portions of the United States.

The wild prototype of Zea has not with certainty been identified. So far as known there is only the one species which includes all the cultivated types and varieties of maize.1

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209. Roots. The form and habit of growth of the roots of maize are similar to those of wheat, although modified somewhat in position, due doubtless to the plant being in hills or drills instead of being broadcast. The general tendency is for the roots to grow somewhat horizontally for one or two feet and then turn down more or less abruptly. The position of the roots is modified by the depth of fertile soil and by depth to which the seed bed has been stirred. The indications are that the distribution of roots depends more upon a proper supply of oxygen and water than upon temperature. The following table shows a Brace roots on Mexnumber of roots at six inches from the plant at different depths in plants one to six weeks old as examined in a black prairie soil at the Illinois Station:

ican maize grown at lowa Station farm (after King).

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1 For a summary of the evidence concerning the wild prototype of maize, see Maize: A Botanical and Economic Study. By John W. Harshberger. Contributions from the Botanical Laboratory of the University of Pennsylvania, Vol. 1, No. 2.

N. Y. State (Geneva) Rpt. 1887, p. 95; 1888, p. 171.

Observations made in Alabama, New York, North Dakota, Iowa and elsewhere, have shown that the roots grow horizontally for some distance from the plant, within four inches of the surface. These lateral roots are very abundant, especially in the early part of the season. Later in the season, however, roots are sent downward in greater number, the lateral roots meanwhile continuing to grow and rebranch, so that in the course of eight to ten weeks the soil between the hills, under ordinary culture, is completely occupied by a dense ramification of roots. One hundred branches have been counted on a piece of maize root fourteen inches long. Many instances have been reported of roots growing four feet deep, and in some cases roots have been broken off at a depth of fifty inches, showing that they must have grown somewhat deeper. Hays reports maize roots eight feet in length, although not in depth. In most soils, however, the amount of root surface below the first two feet is comparatively small. This suggests that the relatively few unbranched roots which descend to greater depth do so to supply the plant with water. The requirements of the plant for water are very great, both because of the large amount of dry matter per acre produced and because the season of active growth is during the hottest portion of the year.

In the early stages of the plant the root growth is rapid. A maize plant one-half inch high has been observed with a root eight inches long; one three inches high with a root thirteen inches long, and two five inches high with roots eleven to twentyfour inches long. Unlike the wheat plant, which throws out a whorl of three temporary or seminal roots, the radicle of the maize plant enlarges and remains prominent, while two or three other roots of lesser size are thrown out. Compared with the lower portion, the stem is very much enlarged at the point where the permanent or coronal roots begin. In a plant thirty days old and twenty-one inches high the stem between the temporary and permanent roots was one-sixteenth of an inch in diameter,

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