``Cultivation and tillage of the soil'' includes all the operations
necessary to prepare a suitable seedbed, eliminate weed growth, and
improve the physical condition of the soil. Thus, grading or leveling
land or removing rock or other matter to prepare the ground for a proper
seedbed or building terraces on farmland to check soil erosion are
included. The application of water, fertilizer, or limestone to farmland
is also included. (See in this connection Secs. 780.128 et seq. Also see
Farmers Reservoir Co. v. McComb, 337 U.S. 755.) Other operations such as
the commercial production and distribution of fertilizer are not
included within the scope of agriculture. (McComb v. Super-A Fertilizer
Works, 165 F. 2d 824; Farmers Reservoir Co. v. McComb, 337 U.S. 755.)
