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Cayton David Walter, Johnson Leslie William: Precision depth seed planter. Deere & Company, July 31, 1973: US3749035 (82 worldwide citation)

A precision depth planter including a plurality of furrow-forming units mounted on a main frame for relative vertical movement, each unit including a pair of depth gauge wheels for carrying the unit and for regulating the depth of the furrow formed thereby. A seed dispensing unit is mounted on the f ...


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