osier

noun3

1. •
   A willow, of species Salix viminalis, growing in wet places in Europe and Asia, and introduced into North America, considered the best willow for wickerwork.
2. •
   Any kind of willow.
3. •
   Long, pliable twigs of this plant, or of other similar plants.

   • Wattling consists of a row of upright stakes the spaces between which are more or less filled by interweaving small branches, hazel rods, osiers, reeds, thin strips of wood, or other pliant material. — 1952