Examines the bases of agricultural change and peasant choice in Ban Ping, a Northern Thai Lue village. Relates plow and tractor farming to each other and to the environment. Delineates the physical and social forces that determine the farmer's choice among practices available to him. Describes plow agriculture tools and tasks, contrasting farming practices in Ban Ping with Thunglor, a rice-growing village in Central Thailand. Discusses the effects of plow and tractor agriculture on village and extracommunity relations. Contrasts agricultural progress in North and Central Thailand with Japan and Java. Studies alternatives in acquiring land and mobilizing labor. Follows up 1960 research with a description of Ban Ping's farming in 1965, discussing the forms of significant change. (This documents is a revision and expansion of Dr. Moerman's doctoral dissertation, TIC Accession Number 13119). [TAIC]