Aspen

Aspen are a specific group of poplar trees. Their wood is used in wand-making.

Wandlore
Wand-quality aspen wood is white and fine-grained, and highly prized by all wand-makers for its stylish resemblance to ivory and its usually outstanding charmwork. The proper owner of the aspen wand is often an accomplished duellist, or destined to be so, for the aspen wand is one of those particularly suited to martial magic.

An infamous and secretive eighteenth-century duelling club, which called itself The Silver Spears, was reputed to admit only those who owned aspen wands. Garrick Ollivander often found that aspen wand owners are generally strong-minded and determined, more likely than most to be attracted by quests and new orders; this is a wand for revolutionaries.