Plant life / by Maxwell T. Masters.

  • Maxwell Tylden Masters
Date:
1885
Catalogue details

Licence: Public Domain Mark

Credit: Plant life / by Maxwell T. Masters. Source: Wellcome Collection.

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    ripening of seeds, while its effect on the growth of turnips is familiar to all practical men. Iron is essential to the formation of leaf-green—“chloro- phyll”—and chlorophyll is essential to the production of starch ; hence iron in some shape is essential to plants, and it also is supplied from the soil in the form of saline solutions. What precise function lime plays in the plant’s economy is not known; hut indirectly it is of importance as a means of introducing phosphorus and other essential ingredients. At Rothamsted, in two of the plots upon which barley has been grown for thirty years in succession, a mineral manure with nitrogen has been applied; but in the one case lime has been added, in the other (otherwise treated exactly in the same way) no lime has been added. The plants on the plot without the lime are always of a darker green colour, but they are relatively deficient in carbon. Under equal conditions, it is seen that the amount of carbon assimi- lated from the atmosphere in the manner to be hereafter mentioned is directly dependent on the amount of available nitrogen, which latter is derived from the soil—(Lawes and Gilbert). It must not be forgotten that the substances we have mentioned, as well as others not alluded to, though possibly not directly concerned in the nutrition of the plant, yet are so indirectly by causing changes in the soil, by render- ing some matters soluble and capable of osmotic absorption which would not be so without their aid, by storing up and preventing the waste of ingredients useful as plant food, and so forth ; but these matters pertain rather to the physical and chemical history of the soil, on which account they may be passed over here without further mention.
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