Note 64 — Chapter X · SOIL AND SUBSOIL (Continued)
Reading edition
Shaler (Origin and Nature of Soils; 12th Rept. U. S. Geol. Survey, p. 311) says: “Annual plants cannot in their brief period of growth push their roots more than six to twelve inches below their root-crowns”—a generalization measurably true for the humid region only. According to F. J. Alway, the roots of cereals penetrate to 5-7 feet in Saskatchewan, also.