"Banksia menziesii" grows either as a gnarled tree to , or a lower spreading shrub, generally encountered at its northern limits in the vicinity of Eneabba-Mount Adams; thus, it declines steadily in size as the climate becomes warmer and drier further north. In the shrub form, several stems arise from the woody base known as the lignotuber. The trunk is greyish, sometimes with shades of brown or pink, and the thick rough bark breaks away easily. The new growth is covered in fine brownish hair, which wears away after two or three years, leaving smooth stems and leaves. Stems that will bear flower spikes the following year are generally thicker and longer. Oblong in shape and somewhat truncate at the tips, the leaves are grey-green in colour, long and up to wide. The new leaves are paler and finely downy. The leaf margins are serrated with many small 1–2 mm long triangular teeth. The lower surface of the leaf has a midrib covered in fine pale brown hair.