The use of draglines and mechanical shovels to uncover and remove coal from surface mines has greatly increased in importance in the last 20 years. Strip mining, as this is called, has resulted in a greater per man day coal production and a greater percentage recovery of coal. Along with this increased production and increased efficiency in the use of one resource there occurs a change in the use capability of land mined for coal.
Proceedings of the Iowa Academy of Science
©1955 Iowa Academy of Science, Inc.
Einspahr, Dean W.; McComb, A. L.; Riecken, F. F.; and Shrader, W. D.
"Coal Spoil-Bank Materials as a Medium for Plant Growth,"
Proceedings of the Iowa Academy of Science, 62(1), 329-344.
Available at: https://scholarworks.uni.edu/pias/vol62/iss1/36