Crop thinning apparatus and method

A method and apparatus for mechanically thinning crops, particularly those planted in rows. One or more crop thinning units are connected to the back of a tractor or other vehicle. Each of the units has the ability to sense plants and activate an arm which has a blade disposed thereon. An electronic control system enables data from several sensors to be evaluated such that plants may be selectively removed based on pre-established criteria. Sensors differentiate between weeds and plants, and maintain the cutting units above the crop rows.