The school and farmA treatise on the elements of agriculture . ich then breaks open its outer covering orhusk. In the bean, for instance, this takes place veryreadily. We then see what looks like two thick separate a little, allowing a little tip, the germ,between them to expand likewise and to grow the same time it develops tiny roots at its basewhich rapidly grow downward into the soil. As theroots grow and become fibrous, the stalk grows higher,bringing the two leaves above ground, and developingnew and proper leaves. The first two leaf-like growthswere not true leave
The school and farmA treatise on the elements of agriculture . ich then breaks open its outer covering orhusk. In the bean, for instance, this takes place veryreadily. We then see what looks like two thick separate a little, allowing a little tip, the germ,between them to expand likewise and to grow the same time it develops tiny roots at its basewhich rapidly grow downward into the soil. As theroots grow and become fibrous, the stalk grows higher,bringing the two leaves above ground, and developingnew and proper leaves. The first two leaf-like growthswere not true leaves but only bags containing food forthe young plant. They wither and drop from theplant when their food supply has been used up. The whole process of growth is therefore an unfold-ing of the seed and a developing of its parts in twodirections, upward and downward. In order that it CONDITIONS OF PLANT GROWTH. 33 may take place there is required warmth and Hght,though the plant will make some growth without thelatter. There is no force working on the outside to. Fig. 4—An oak plantstarting from theacorn. Fig. 5—A youngpea-plant. give their natural shape to the roots, stem, leaves andbranches. All these parts w^ere already in the seed;that is, in the germ attached to the kernel. The kernel 34 THE BASIS AND CONDITIONS OF FARMING. itself, apart from the germ, is simply food for theyoung plant until its roots begin to work. (Fig. 5.)The whole further growth of the plant is mainly in-tended to produce new seed. Many plants, after ripen-ing their seeds, wither and die, as for instance all ourregular farm crops, with the exception of grass. Theyare annuals. A plant that needs two years to perfectseed, and then dies, is called a biennial (two-yearplant) ; and one that produces seed year after year iscalled a perennial (lasting for years). The conditions for the growth of a plant may betherefore summed up as follows: 1. Healthy seed. This means that the germ of thenew plant must be uni
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectagricul, bookyear1902
