In
botany, the
petiole is the small stalk attaching the
leaf blade to the
stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called
stipules. Leaves lacking a petiole are called
sessile, or clasping when they partly surround the stem. Clasping leaves of the
Poaceae have an extra structure called the
ligule.
In Acacia koa, the phyllodes are leathery and thick, allowing the tree to survive stressful environments. The petiole allows partially submerged hydrophytes to have leaves floating at different depths; the petiole being between the node and the stem.
>Petiole is pronounced "pet-ee-ohl" and comes from Latin petiolus, or peciolus "little foot," "stem", an alternate diminutive of pes "foot." The regular diminutive pediculus is also used for "foot stalk".
