. Cyclopedia of American horticulture : comprising suggestions for cultivation of horticultural plants, descriptions of the species of fruits, vegetables, flowers, and ornamental plants sold in the United States and Canada, together with geographical and biographical sketches. Gardening; Horticulture; Horticulture; Horticulture. maple injured by chill the root-hairs and irritate the assimilatory organs. The former cease to perform their normal absorptive functions, and from the leaf are gradually withdrawn the substances which are readily made soluble. The cell walls and the less useful parts
. Cyclopedia of American horticulture : comprising suggestions for cultivation of horticultural plants, descriptions of the species of fruits, vegetables, flowers, and ornamental plants sold in the United States and Canada, together with geographical and biographical sketches. Gardening; Horticulture; Horticulture; Horticulture. maple injured by chill the root-hairs and irritate the assimilatory organs. The former cease to perform their normal absorptive functions, and from the leaf are gradually withdrawn the substances which are readily made soluble. The cell walls and the less useful parts are left, and by the formation of a distinct corky layer across the leaf-stalk, where it is attached to the main stem, the plant cuts off its assimilatory organs by a natural process, so that no wound or injury except the well-healed leaf-scar shall mark its fall. In this process the chlorophyll is oxidized and changes from green to some other color, as yellow or red; and often it is by this means that the beautiful autumn colors are developed. These colors also serve very likely as a protection to shield twigs and trunks from the hot autumn sunshine. Likewise, the twigs themselves may be provided with color for the same purpose. The old leaves are dropped in the autumn, but al- ready a new set of modified leaves in the form of bud- scales have been formed, in turn to be defoliated the next spring, after serving a term of winter protection. Deciduous trees then shed their summer leaves when growth ceases and their winter leaves when growth is awakened. Plants such as the squash and potato may be killed by a degree of cold less than the freezing point. It is because the protoplasm of the cells is stimulated to give up its water into the spaces between the cells, and then not being held by the protoplasm, this water is readily evaporated and the plant dies from being dried out. In the same way a plant may wilt and eventiially be much injured if cold water is applied to its roots.
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Keywords: ., bookcentury1900, bookdecade1900, booksubjec, booksubjectgardening
