. The cereals in America. 30 THE CEREALS IN AMERICA at least fift}'-two spikes have been produced from a single seed. The " stand " of wheat may be materially affected by the amount of tillering, and, therefore, a study of those conditions which wall promote tillering is advisable. On the other hand, it is probable that the best yields are not obtained where too much tillering is encouraged through thin seeding. «In starting from the seed the stem soon begins to branch. The first leaves which are sent up seem to be a temporary set of organs designed to quickly reach above the soil, t
. The cereals in America. 30 THE CEREALS IN AMERICA at least fift}'-two spikes have been produced from a single seed. The " stand " of wheat may be materially affected by the amount of tillering, and, therefore, a study of those conditions which wall promote tillering is advisable. On the other hand, it is probable that the best yields are not obtained where too much tillering is encouraged through thin seeding. «In starting from the seed the stem soon begins to branch. The first leaves which are sent up seem to be a temporary set of organs designed to quickly reach above the soil, that the plant may be supplied with green cells in the sunlight. These leaves form what appears to be the primary shoot of the plant, and spring from the stem near the seed. They are found to be dead in the spring, along with the germ whorl of roots, in case of several varieties of winter wheat. At the same point where these first leaves arise another stem, apparently a rhizome, branches off from the primary stem. This rhizome has an inter- node quite unlike all the other lower intemodes, not even covered by the sheath of a leaf, and extending about half way to the surface of the soil. In case the seed is planted two inches deep this rhizome is about one inch long. At the top of this intemode a joint bears a leaf, and a few other joints follow at very short intervals, each having a bud in the axil of its ; 2. ^mi A stool of wheat. Culms are from a single seed originally at a. One-third natural size. 56. The Organs of Reproduction.— The flower of the wheat plant has three stamens. The anthers are attached to the tapering end of the thread-like fila- ments below the middle. As the flower opens the filaments rapidly elongate, pushing up and outside of the glumes the anthers which previously were closely packed about the ovu- lary.^ The attachment of the filament to the anther is such that the anther suddenly upsets and the pollen falis out of 1 Neb. Bui. 32, p. 91. 2 M
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Keywords: ., bookauthorhuntthom, bookcentury1900, bookdecade1900, bookyear1904
