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lasts till August ist. Everywhere east of the Great Plains. wheat is cut as soon as or a little before it is ripe, and the harvest extends on any one farm not longer than two or three weeks, the wheat being cut as fast as it is ready. In California, where there is no danger from rain, the harvest extends for many weeks after the wheat is ripe, some of it standing even ten weeks after it is ripe enough to cut. The only damage done to the standing wheat in this section is by occasional sand storms. 'he type of wheat usually raised is the club or square head, whose short culms prevent it from lodging.

The calendar of the wheat harvest of the world is given by Edgar as follows:

"In January, Australasia, Chili and Argentina; in February and March, East India, Upper Egypt; in April, Lower Egypt, Asia Minor and Mexico; in May, Algeria, Central Asia, China, Japan and Texas; in June, Turkey, Spain, southern France, California, Tennessee, Virginia, Kentucky, Kansas, Utah and Missouri ; in July, Roumania, Austria-Hungary, southern Russia, Germany, Switzerland, France, southern England, Oregon, Nebraska, southern Minnesota, Wisconsin, Colorado. Washington, Iowa, Illinois, Indiana, Michigan, Ohio, New York, New England, eastern Canada; in August, Holland, Belgium, Great Britain, Denmark, Poland, western Canada, the Dakotas; in September and October, Scotland, Sweden, Norway, North Russia; in November, Peru and South Africa; in December, Burmah and Argentina.” 1

158. Stage of Maturity on Yield.—The usual practice in the eastern half of the United States is to cut when the straw begins to turn yellow and the grains are in the dough, soft enough to be easily indented with the thumb nail and hard enough not to be easily crushed between the fingers. Investigations indicate that there is a continuous increase of the plant during its growth until the plant is entirely ripe. There is a continuous increase in the weight of the grain from the time it is formed until it is hard and dry. The increase in weight of grain is most rapid up to the time when the grain can be crushed between the thumb and finger. The increase seems to be decided and of economic importance up to the time when the grains indent but

1 Wm. C. Edgar: Story of a Grain of Wheat (1903), p. 191.

do not crush under the pressure of the thumb nail. After that time the increase is slight. The indications are that if allowed to stand beyond the period of full maturation, a slight decrease in the actual substance of the grain may take place. This is explained by Deherain on the ground that the seed continues to respire, thus giving off carbon dioxide.

159. Influence of Ripening Upon Composition.-In general, there is a decrease in the percentage of ash, nitrogen and fiber as the grain ripens, due to the increase in carbohydrates other than fiber. This is due to the endosperm developing later in the growth of the wheat. The germ develops first, and later, when the endosperm develops, the percentage of ash and nitrogen becomes less, although the actual amount may remain the same, or, as is probably the case, may increase. The changes in composition after the grain has reached the dough stage appear to be very slight.

While the stage of maturity of grain through the ordinary range of wheat harvest does not affect materially the quality (composition) of the grain, climatic conditions which affect the full maturity of the grain may materially modify the quality. The higher percentage of nitrogen in the spring wheat is probably due, in part at least, to a lack of full maturation. (74) The per cent of nitrogen decreases somewhat in the straw up to the dough stage. The per cent of crude fiber increases in the straw throughout the ripening period, while there are corresponding decreases in the other carbohydrates.

160. Influence of Shocking.—There is always danger of overripe grain shelling out in the harvesting, and there is also danger of lodging. It is not good farm practice, therefore, to delay harvesting until wheat is entirely ripe. Investigations have proved beyond question that at the early stages of seed formation a considerable transfer of material from the straw to the grain may occur after cutting, when the wheat is placed in a condition similar to the shocking and capping of bound sheaves. Prompt shocking and capping, therefore, facilitate the completion of the ripening process. Where it is necessary to cut the wheat quite green, it is important that the sheaves should not be left long on the ground exposed to the hot sup

1 Mich. Bul. 101, p. 8.

161. Method of Shocking.–The sheaves may be put in long shocks by placing pairs of sheaves in a row, about a dozen bundles to the shock, or preferably in round shocks with caps, twelve to sixteen bundles to the shock, depending upon the size of the bundles, the stage of maturity and the amount of green weeds. In building a shock of twelve bundles, place three pairs in a row, then place two bundles on each side, making ten bundles. Now lay one bundle on the top, then take another bundle, break both ends of the bundle at the band, spreading the ends fan-shape, and lay this crosswise of first bundle. In some cases only one bundle is used, treating it as just indicated, and in other instances the caps are entirely omitted. Usually, however, capping with two bundles is to be preferred. In building a shock of sixteen bundles, place four pairs in a row, then three bundles on each side, and cap with two bundles. Both for efficiency and economy of time, two bundles should be handled at once, and care should be taken to place the bundles firmly on the ground. There is a knack in shocking that may be easily learned by practice, which adds greatly to the ability of the shocks to withstand wind storms

162. Methods of Harvesting—There are four types of power machines for harvesting wheat and other stored grain in the United States at the present time. They are: (1) the self-rake reaper; (2) the self-binding harvester ; (3) the header; and (4) combined harvester and thresher. The hand cradle is still manufactured and used for harvesting small areas.

1 Ill. Buls. 11 (1890), p. 349, and 22 (1892), p. 119. Mich. Bul. 125 (1895), p. 34.

163. Self-Rake Reaper.—All harvesting machines have certain features in common. These are the serrated sickle vibrating through stationary guards, a platform to receive the cut grain, some provision to bring the grain regularly against the sickle and deposit it on the platform, a divider to separate the swath

to be cut from the remainder of the standing grain, and some means by which the operator can quickly raise or lower the cutter bar while the machine is in motion.

In the self-rake reaper The self-rake reaper.

the platform has the form

of a quarter of a circle, and upon it operate automatically rakes which serve the double purpose of bringing the grain onto the platform and removing it from the platform far enough to one side so that the reaper can again pass around the field without running over the cut grain. The size of the bundle is determined by regulating the number of rakes which remove the grain. Because of the necessity of binding the grain by hand, they are used only where small quantities are to be harvested. The reaper cuts a swath of five feet and is drawn by two horses. An ordinary day's work is from six to eight acres.

The self-binding harvester. 164. The Self-Binding Harvester.—By far the larger area of small grain is now harvested by this machine, generally called the “binder.”

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They are manufactured in a number of styles, but in their essential features they are nearly all practically identical. It differs from the reaper in having a reel to bring the grain against the cutter bar and deposit it on the platform. This reel is attachable at the will of the operator while the machine is in motion. The cut grain is conveyed on an endless canvas to an elevator consisting of two endless canvases which deposit the grain on the opposite side of the drive wheel, where it is packed into a trim bundle and automatically bound with twine. The binding device operates as often as the pressure of the increasing bundle trips it. The size of the bundle is therefore determined by regulating the pressure required to trip the binder. Binders are made which cut different widths, the standard width being six feet. Three horses are used with the sixfoot cut, and an ordinary day's work is from ten to twenty acres, depending upon many factors, the most important of which are the yield and the condition of the straw.

165. The Header.—The header and the combined harvester can be used only where the climate is such as to permit harvesting the wheat after it is fully ripe and thoroughly dry, and hence are in use only in the western half of the United States. Instead of cutting the wheat near the ground, they merely head it, leaving the bulk of the straw standing in the field. The header conveys the headed grain to the side of the machine and elevates it so that it is deposited in a wagon driven alongside to receive it. The grain is either immediately carried to a threshing machine or first put in stacks and subsequently threshed.

The header,

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