Virginia Tech, Extension Service2019-11-082019-11-081945-03-23http://hdl.handle.net/10919/95382General surface condition of area tilled by sub-surface implements. Left: Duckfoot tiller equipment; Right: Sweep equipment.negative, 3.5 x 5 in.image/jpegIn CopyrightApplied ScienceAgricultureVirginia Extension - Project 10Agricultural EngineeringStubble MulchErosion ControlSoil and Water ConservationPhotographBiological Systems Engineering, Virginia Tech