Method and apparatus for using electrical current to destroy weeds in

Abstract

A method and apparatus for destroying weeds growing in and around crop rows without destruction of crops growing therein. A plurality of electrically conductive spring members are disposed in a generally horizontal plane and connected to a high voltage source of electricity. The spring members have a spring constant such that relatively stiff crops plants will deflect the spring members while relatively flexible weeds will not deflect them. Substantially all of the plants in and around the crop rows are contacted with current-carrying portions of the spring members by moving the spring members relative to the crop rows parallel to the crop rows. A larger dwell time of contact is provided between the spring members and the relatively flexible weeds then the dwell time of contact between the spring members and the relatively stiff crop plant so that the weeds receive sufficient electrical energy to result in destruction thereof, while the crop plants do not receive sufficient electrical energy to result in destruction thereof. The difference in dwell time is provided by forming each spring member so that it has one end connected to a supporting member and the first portion extending from the connected end making a first angle .alpha. with a line along the direction of movement of the spring member, and having a free end with a second portion adjacent the free end making a second angle .beta. with a line along the direction of movement of the spring member, the angle .beta. being substantially greater than the angle .alpha., and by disposing the connected end of the spring member between crop rows while the free end extends into a crop row during movement of the spring member to affect contacting.