Download RAW file: https://library.csbe-scgab.ca/docs/journal/17/17_2_124_raw.pdf
There is an interest on the part of research workers, practicing engineers and machinery managers to obtain observations, or predictions of the hours available each year for various field machine operations. The amount of time in which the field conditions are suitable for plowing, cultivating, planting, raking, baling, combining, etc. is an important input for decisions on sizes of machines or systems of machines needed for crop production. The extent to which drainage improvements can increase the time avail able for field operations is an important item in attempting to assess the benefits of drainage works. Some progress has been made in using water balance models to predict available workdays from weather data. This paper is an attempt to clarify points which have been subjected to inaccuracy and con fusion in tractability research because of insufficient care with terminology in some published papers. Some field measurements are also included in this paper, from which workday criteria for tillage and planting for the soils under investigation were deduced.
soil moisture criteria for tractability
Hassan, A.E. and R.S. Broughton 1975. SOIL MOISTURE CRITERIA FOR TRACTABILITY. Canadian Agricultural Engineering 17(2):124-129.
124 - 129