It has an acute to sub-peltate apex and an amplexicaul base. The base of the lamina is attenuate, amplexicaul, and often decurrent. The alternate leaves are nearly sessile and may clasp the stem (i.e. amplexicaul). Leaves occur in two ranks; stipules are amplexicaul (enclosing the bud). The leaves are neither decurrent nor amplexicaul. The cauline leaves are generally two, sessile, amplexicaul and lanceolate-shaped with a trilobed apex. Upper leaves are sessile, "amplexicaul" (their base is embracing the stem) and more lanceolate. It has an acute apex and its base is gradually attenuate and amplexicaul. The petiole is canaliculate, up to long, and bears an amplexicaul sheath. The specific name refers to the amplexicaul leaves (leaves grasping the stem). Its base is a broad, amplexicaul sheath with decurrent margins. There are amplexicaul (clasping the stem) sheathing stipules. The base of the lamina is amplexicaul. The leaves are alternate, sessile or amplexicaul and lobed with spines on the margins. The leaves are amplexicaul and vary from 4 to 7 per plant.