A tillage implement has a main frame provided with ground-engaging wheels that support the main frame at a selected height above the ground. Tillage shanks may be provided on the main frame and, if so, have their depth of penetration into the ground determined by the selected height of the main frame. Gangs of freely rotatable circular blades are carried on the main frame for both fore-and-aft angle adjustment relative to the main frame about respective upright pivot axes and up-and-down depth adjustment relative to the main frame about respective horizontal pivot axes. Such angle and/or depth adjustments can be carried out on-the-go from the tractor seat and without raising or lowering the main frame such that if tillage shanks are provided on the main frame, the working depth of the tillage shanks can remain unchanged as the gangs are adjusted.