. Cyclopedia de cultures agricoles, une étude des cultures populaires et des méthodes de récolte aux États-Unis et au Canada ;. Produits agricoles ; l'Agriculture. Chapitre VII L'ensemencement, LA PLANTATION ET LES RENDEMENTS. lELD cultures sont propagées principalement au moyen de graines, plutôt qu'au moyen de boutures ou d'autres pièces spéciales. De plus, la semence-propagation est de nature plus facile et le plus simple, adaptable aux méthodes de gros. Il n'est pas nécessaire pour l'employeur de greffes ou d'autres pratiques très spécial. Pour ces raisons, l'objet de multiplication est généralement considérée comme appartenant à cette phase de l'agriculture a connu

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. Cyclopedia of farm crops, a popular survey of crops and crop-making methods in the United States and Canada;. Farm produce; Agriculture. CHAPTER VII SEEDING, PLANTING AND YIELDS. lELD CROPS ARE PROPAGATED chiefly by means of seeds, rather than by means of cuttings or other special parts. Moreover, the seed-propagation is of the easiest and simplest kind, adaptable to wholesale methods. There is no necessity for the employing of grafting or other very special practices. For these reasons, the subject of propagation of plants is usually considered to belong to that phase of agriculture known as horticulture. A very few of the field crops are propagated by asexual parts or cuttings of them, as white potato, sweet-potato, sugar-cane, cassava, chicory. Whenever cutting- propagated plants are raised from seeds, the seedlings are likely to vary greatly, so greatly, in fact, that seed propagation may be employed with such plants for the purpose of securing new varieties. The white or Irish potato is a good example; and as this species seeds relatively freely and seedlings are easily grown, the number of varie- ties is very large. The sweet-potato and sugar-cane seed so rarely, at least in this country, that this means of securing new varieties is practically little employed, and reliance must be had on variation through asexual parts. The reason why seeds give such uncertain results in cutting-propagated plants, as potatoes, apples, grapes, strawberries, is because there has been no seed-selection to make them "come true." In the seed-propagated plants, as the cereal grains and garden vegetables, selection has been practiced so long and so carefully that the tendency to vary has been largely bred out. The tendency of seeds to give variable offspring is greatly increased, as a general thing, by crossing, whereby different elements or tendencies are combined.. Please note that these images are extracted from scanned page images that may have been digitally enhance

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