The vitaceae (grape) family is represented in the US by around 30 species, in six genera; the most numerous, with 20 species, is vitis. Plants are vines, bearing alternate leaves, simple or compound (palmate or pinnate), usually with stipules and tendrils. Leaves are usually toothed. Flowers are produced in dense, flat-topped or elongated clusters; they have four or five petals, the same number of petals and the same number of stamens.