Image d'archive à partir de la page 658 de la Cyclopaedia de cultures agricoles . Cyclopedia de cultures agricoles : une étude des cultures populaires et des méthodes de récolte aux États-Unis et Canada Année bailuoft cyclopediaoffarm00 : 1922, c1907-SUCRE DE BETTERAVE À SUCRE DE BETTERAVE 591 Fig. 817. (Dia- grammatic longitudinal j section fleur de betteraves, d, glandes ; /) ; bractées, k, de tissus surrouuiiiug- l'ONU a élaboré des semences. tain que de germes qu'il y avait des fleurs dans le cluster. De temps en temps une fleur se suffit à elle-même et développe une seule semence ; dans d'autres cas, un ou plusieurs des fleurs, seules ou en groupe, ne parvient pas à produire des semences, ce qui

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Archive image from page 658 of Cyclopedia of farm crops . Cyclopedia of farm crops : a popular survey of crops and crop-making methods in the United States and Canada cyclopediaoffarm00bailuoft Year: 1922, c1907 SUGAR-BEET SUGAR-BEET 591 Fig. 817. Longitudinal (dia- grammatic j section of beet flower, d, glands; /), bract; k, tissue surrouuiiiug un- developed seed. tain as many germs as there were flowers in the cluster. Occasionally a flower stands by itself and develops a single seed ; in other instances, one or more of the flowers, either singly or in groups, fails to produce seed, thus reducing the num- ber of seeds, or the num- ber of germs, in the seed-ball. The flowers are five-parted ; that is, there are five stamens and five parts to the corolla. The petals are wanting and the pistil is three-parted. Fig. 817 shows the construction of the beet flower as seen in longitudinal sec- tion. The sepals persist and form a part of the seed-coat, giving to the single - germ seeds the form of a five-pointed star. The individual seeds in the seed-balls are made up in the same way, but the star-shape is not so apparent when the seeds are welded to- gether in the form of balls. Seed plants are shown in Figs. 818, 819. Beet plants are biennial, that is, they produce seed the second season. In those countries where the beet is indigenous, the winters are warm enough so that the plants will live over from the first to the second sea.son ; but in most of our com- mercial sugar-beet sections it is necessary to pro- tect them from frost during the winter. This is usually done by placing them in some form of a silo or pit. One of the common and ipost satisfac- tory methods of pitting consists in piling the beets in the form of a cone or a pyramid on the surface of the ground, having selected for the purpose a well-drained spot. The piles are then covered with straw, which, in turn, is covered with earth; as the temperature falls with the advance of winter, more earth is add

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