Abstract: A wheeled support structure assists in supporting a cutting head of a string trimmer within a cutting plane which is parallel to, but vertically spaced above, ground surface. The wheeled support structure includes a wheel, and an extension shaft having an upper end which is connectable to a main shaft of the string trimmer rearwardly of the cutting head, and a lower end which is journally coupled to the wheel. In such a manner, the wheel is oriented in a rolling plane which is substantially transverse to the cutting plane within which the cutting head of the string trimmer is supported, and is capable of rolling movement over the ground surface. The wheel thereby establishes a point about which the cutting head of the string trimmer may be pivoted by an operator while assisting the operator in maintaining the cutting head of the string trimmer within the cutting plane. Vegetation can thus be cut by the cutting head of the string trimmer at a substantially uniform height throughout an arcuate segment.