I've helped my dad make a couple of cedar strip canoes, but he lives in Maine in the middle of vast cedar forests and 3 miles from a cedar lumber mill. He got off-lengths direct from the lumber mill for a very low price.

For the gunwales he ripsawed a long ash pickpole, getting two nice long hemicircle cylinders.

IMHO, ash will flex more before breaking than walnut and it's lighterweight.