. Development and activities of roots of crop plants; a study in crop ecology. Roots (Botany); Plant ecology; Crops and climate. Investigations at Peru, Nebraska. 27 The potato was examined only twice. The first examination was made May 31, 56 days after planting. The tops were 9 to 12 inches high. At this time the root system was almost entirely near the surface. As many as 55 roots took their origin from the base of a single plant and ran off practically parallel to the surface of the soil. They varied from a few inches to feet in length. None penetrated deeper than feet and with few
. Development and activities of roots of crop plants; a study in crop ecology. Roots (Botany); Plant ecology; Crops and climate. Investigations at Peru, Nebraska. 27 The potato was examined only twice. The first examination was made May 31, 56 days after planting. The tops were 9 to 12 inches high. At this time the root system was almost entirely near the surface. As many as 55 roots took their origin from the base of a single plant and ran off practically parallel to the surface of the soil. They varied from a few inches to feet in length. None penetrated deeper than feet and with few exceptions were throughout their length within the first 8 inches of soil. The earth about the plants was so thoroughly filled with these roots that it was found impos- sible to represent all of them in one plane. Consequently the drawing (fig. 10) shows but one-half of the entire root system. Some of the roots were confined to the first 2 inches of soil. As is shown in figure 10, a number of the deeper roots had a tendency to turn quite ab- ruptly downward. A dry period of short duration occurred at this time, and. Fig. 10.—One-half of root system of a potato plant 56 days old. it was uncertain whether this downward turn was normal or whether it was a response to low water-content of the surface soil. The dry weather may have had some influence, but subsequent investigation indicated conclusively that this habit of growth is normal. The main roots were densely covered with thread-like branches from a few millimeters to 3 or 4 inches in length. So numerous were these capillary branches that the soil to the very surface was thoroughly penetrated by them. Several young potatoes from to 2 cm. in diameter had formed. This period, excepting the last part of May, had been rather unfavorable for growth, because of cool weather. The soil-temperature to a depth of 2 feet averaged but ° F. This was due in part to the high water-content of the soil resulting from the heavy Apr
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectcropsan, bookyear1922
