Root development of several common forage grasses to a depth of eighteen inches
1948
Gist, G.R. | Smith, R.M.
Root samples of bromegrass, orchard grass, Kentucky bluegrass, timothy, and deer's tongue were collected from experimental plots on the agronomy farm at Morgantown, W. Va. These plots were on shallow Rayne silt loam. The root and soil samples were taken by means of a core type sampler 3 inches in diameter. Cores were taken to a depth of 18 inches and cut into 3-inch segments for soil testing and root removal by washing. In some cases solid sandstone rock was encountered at depths from 16 to 18 inches, in others a loose porous sandstone or shale was found to extend below the 18-inch level. Except in cores where solid rock was encountered, some roots extended below the 18-inch level. In the 0 to 3-inch layer deer's tongue had the greatest root development with 4,481 pounds of roots per acre inch as compared to 1,247 for orchard grass, 1,126 for Kentucky bluegrass, 717 for bromegrass, and 680 for timothy. In all samples, weights of roots per acre inch decreased rapidly with depth. At depths below 6 inches, bromegrass had greater root development than the other grasses studied. In the 12- to 18-inch layer, bromegrass had 106 pounds of roots per acre inch; orchard grass, 29; deer's tongue, 16; timothy, 6; and Kentucky bluegrass, 3. The organic matter content of the soil decreased consistently with depth. It was significantly higher in the 0 to 3-inch layer than in the 3- to 6-inch layer, even though the plots were plowed to a depth of about 6 inches 3 years earlier. This higher organic matter content in the 0 to 3-inch layer was evidently the result of the build-up by the grasses and clover. It was greatest for the grasses with the heavier root systems in the surface layer.
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