Abstract: An implement for contact application of liquid herbicides comprises an ultra-lightweight frame supporting a wiper bar and mounted on a tall narrow wheels, and sized so that it can be drawn through a field by a motorcycle without trampling the crops. The wiper bar includes a stiff structural support member enclosed in a sponge or synthetic chamois material and a distribution conduit extending along the wiper bar with small outlet orifices for discharging herbicide liquid into the material along an upper side of the wiper bar. Liquid is supplied to the wiper bar through a gravity feed system including a tank, drip valves, and feed lines arranged to provide a head of liquid above the wiper bar to keep the distribution conduit constantly filled with liquid along its entire length even under sloping field conditions. The distribution conduit is of minimal diameter to contain a minimum weight of liquid and to restrict the flow of liquid therethrough.