Tire with improved traction

Agricultural or forestry tire (10) comprising a tread (11) provided with a base surface (14) and with a plurality of ribs (12), each rib (12) being provided with a head (16), a front wall (13) and a rear wall (25), wherein, on the front wall (13) of the rib (12), under a top portion (13′) of the front wall (13), a shaped profile (15) is present, with a bottom of the shaped profile (15) in the portion of the tread (11) comprised between the front wall (13) of the rib (12) and the adjacent rib, height equal to a portion of the overall height of the front wall (13) of the rib (12) and a length that extends in the transverse direction with respect to the height of the rib (12), and wherein said shaped profile (15) is not present on the rear wall (25) of the rib (12), wherein said shaped profile (15) has a section that defines at least one flat surface (17) of the shaped profile (15), wherein said flat surface is joined to said top portion (13′) of the front wall (13) of the rib (12) by means of a connecting surface (18), and wherein the shaped profile (15) comprises at least one sharp corner (19) and a front wall (23) which is joined to said base surface (14) of the tread (11) by means of another connecting surface (21), characterized in that said flat surface is parallel, or inclined at an angle a up to 200, with respect to the surface of the head (16) of the rib (12) and the shaped profile (15) is obtained by addition of material to the front wall (23) of the rib (12), and wherein said flat surface (17) of the shaped profile (15) is larger in correspondence of the middle of the rib (12).