Possible Clues:

• Walter --, American pioneer aviator
• Source of firewood
• Stately shade tree
• Tree with smooth gray bark
• Drone, perhaps, initially caught high in tree
• Canvas for many an arborglyph
• Tree in coastal stretch, we hear?
• Hardwood tree with thin bark
• Tree in land close to sea, we hear
• Tree whose name sounds like a place to build a sandcastle