What does this phrases mean a long pliant plank?

A long, pliant plank is a flexible piece of wood that is long and thin. It can be used for a variety of purposes, such as building bridges or fences, or as a support for other structures. The word "pliant" means "capable of being easily bent or folded". So a long, pliant plank is a piece of wood that can be easily bent or folded into a desired shape.