Y:
D: harvest - combine & caterpillar
C: harvest - combine & caterpillar;
in ca 1938 oliver ruud traded his horses and bought a gas tractor 
(from webb tractor; consumed 50 gal gas daily);
later he got a diesel;
he was second to last in waterville area to give up harvesting
with horses;
he sold his last team of percherons ca 1950
and got a small wheel tractor for odd jobs.
photo: from 2.1x2.9 negative; 1600 ppi.