Abstract: An agricultural planting machine has a pair of adjacent furrow opening disks that form a V-shaped furrow as the machine advances and a pair of ground engaging gauge wheels respectively mounted for rotation adjacent the opposite sides of the opening disks. The gauge wheels are journaled on the lower ends of a pair of arms having their upper ends attached to the planter frame by mechanisms that permit easy lateral adjustment of the arms to optimize the close spacing between the gauge wheels and the opening disks. Each adjusting mechanisms includes an externally threaded bushing mounted on a shaft and engaging an internally threaded bore in the gauge wheel arm so that rotation of the bushing laterally shifts the arm and the gauge wheel mounted thereon. A locking device is operative between the bushing and the shaft to selectively lock the adjusting mechanism in the desired position.