Tractor compaction of Davidson loam and Cecil clay in test bins at various moisture contents showed relationships between soil moisture and compacted vol. wts. that were generally comparable with relationships arrived at from use of modified Proctor laboratory compaction procedures. Tractor draft-vol. wt. relationships indicated that greatest compaction occurred at less than 1200 lbs. drawbar pull when treatments of 10 tire passes were imposed. Indicated peak compaction in both soils under the treatments imposed occurred at moisture contents near the lower plastic limits and opt. plowing moisture. The results showed that compaction can be reduced by operating tractors when practicable at moisture contents less than the opt. for plowing.