Wooden bowls with square or winged edges can be functional or ornamental. I select wood with outstanding figure for the winged bowls. All of these bowls are 8-12 inches wide. Ambrosia maple is very well suited for winged bowls due to the remarkable gray and brown streaks. The ambrosia streaks are caused by the ambrosia beetle, which attacks unhealthy maple trees. The beetle introduces a fungus which causes the tree to spalt and develop the streaks.