1
Gary D Hodapp: Telescoping row marker. Hiniker Company, Emrich Lee Brown & Hill, August 28, 1984: US04467872 (18 worldwide citation)

A telescoping row marker for use with a conventional agricultural tillage apparatus such as a tractor carried, or pulled, planter, cultivator or the like; for the alignment of soil working implements with crop rows is disclosed. Positioned within a hollow mounting bar open at both ends are first and ...


2
Rogers Jr J O: Telescoping row marker. June 5, 1973: US3736990 (4 worldwide citation)

This invention consists of a steel tube that is mounted on and at right angle to a tractor. The aforesaid steel tube is rectangular when viewed from the end and has two steel tubes that are round when viewed from the end mounted in the first mentioned steel tube. The aforesaid two steel tubes are eq ...