Related Clues:

• Painter's medium
• Beech or birch
• One may undergo surgery
• See 71-Across
• Sloth's hangout
• Crankcase contents
• Heat source
• Theme of the puzzle
• Genealogy chart
• Orchard unit
• Family portrait, of sorts
• Pecan or walnut
• Certain cartel's concern
• Bat's beginning
• Part of a copse