From the Library of Congress Flickr stream "1930's-40's in Color" is this picture of a unique corn harvesting technique and machine:
Click to make large.
LoC Photo Stream data (and active link):
Harvesting new corn from the field of Jim Norris, Pie Town, New Mexico (LOC)
Lee, Russell, 1903-1986,, photographer.
Photographed October 1940.