Related Clues:

• Hardwood
• Refuse
• Rowan, e.g.
• Volcano detritus
• Hearth residue
• Grateful?
• Flue residue
• Cigarette waste
• Shade tree
• Durable wood
• Grate expectations?
• Effect of auto exhaust
• Soda ___
• Urban haze
• Object of E.P.A. monitoring