Radial agricultural tire with a pitched tread

An agricultural tire having a radial ply carcass, an axis of rotation and an annular tread radially outwardly and integrally attached to the radial ply carcass, the annular tread having a first and a second lateral edge and an equatorial plane, the equatorial plane being defined as a plane perpendicular to the axis of rotation and equidistant from the first and second lateral edge, a first and a second set of lugs, the first set having a plurality of substantially parallel lugs extending angularly from the first tread edge toward the equatorial plane, the second set having substantially parallel lugs extending from the second tread edge toward the equatorial plane, the second set of lugs being angularly inclined similar to but opposite in hand relative to the first set of lugs, the tire tread characterized by:

• the tread being divided into a plurality of circumferentially repeating design cycles, the design cycles having at least two different design cycle lengths, including a small length (S) and a large length (L), the ratio of the large length to the small length being at least 1.1:1 each lug of one set being circumferentially offset by about one-half a design cycle relative to the circumferentially adjacent lugs of the other set, each lug has a radially outer surface, the surface being bounded by a leading edge, a trailing edge, an axially outer end and an axially inner end, the average distance between the leading and trailing edges defining the radially outer lug width (W), the width (W) of each lug being proportional to the design cycle length encompassing a majority radially outer surface of the lug, wherein the tread has a volume of lug rubber proportional to the length of the design cycle such that the mass of tread rubber circumferentially positioned around any 90.degree. portion of the tire is uniform within plus or minus 5% and the tread has a total lug contacting surface area, when measured using a normally inflated and loaded tire contacting a flat hard surface as a percentage of the total area between the first and second lateral edges measured 360.degree. around the tire of less than 30%, wherein the lugs of the first and second set have a lug height l.sub.h, l.sub.h being equal to or greater than R1, R1 being an industry standard lug depth specification for agricultural tire of a particular size.