Determination of crop residue cover using scanning microdensitometry

ABSTRACT: Percentage of land covered with corn (Zea mays L.) residue was determined using a scanning microdensitometer. The effectiveness of this densitometric technique was evaluated by comparing the results with those obtained using two conventional approaches, the line-transect (bead-string) method and the photographic method, over a range of cover and topographic conditions. The densitometric method produced results similar to the conventional methods in less time than the bead-string method and with less eye strain than the photographic method. However, the densitometric method underestimated the percent cover with very rough surfaces, such as created by the chisel plow and the till-plant system.