. Dry-farming; a system of agriculture for countries under a low rainfall. Dry farming. WATER MOVEMENT IN PLANT 171 dinarily, it varies from one foot to six feet per hour, though observations are on record showing that the movement often reaches the rate of eighteen feet per hour. It is evident, then, that in an ac- tively growing plant it does not take long for the water which is in the soil to find its way to the upper- most parts of the plant. The work of leaves Whether water., .„ ,, .^ , ^, . ^ . Fig. 40. Magnified root-nairs, showing passes upward from how soil particles are attached to t
. Dry-farming; a system of agriculture for countries under a low rainfall. Dry farming. WATER MOVEMENT IN PLANT 171 dinarily, it varies from one foot to six feet per hour, though observations are on record showing that the movement often reaches the rate of eighteen feet per hour. It is evident, then, that in an ac- tively growing plant it does not take long for the water which is in the soil to find its way to the upper- most parts of the plant. The work of leaves Whether water., .„ ,, .^ , ^, . ^ . Fig. 40. Magnified root-nairs, showing passes upward from how soil particles are attached to them. cell to cell or through especially provided tubes, it reaches at last the leaves, where evaporation takes place. It is nec- essary to consider in greater detail what takes place in leaves in order that we may more clearly under- stand the loss due to transpiration. One half or more of every plant is made up of the element carbon. The remainder of the plant consists of the mineral substances taken from the soil (not more than two to 10 per cent of the dry pknt) and water which has been combined with the carbon and these mineral substances to form the characteristic products of plant life. The carbon which forms over half of the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Widtsoe, John Andreas, 1872-1952. New York, The Macmillan company
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectdryfarm, bookyear1912
