Related Clues:

• It runs in the woods
• Drain of resources
• Gullible person
• Tree fluid
• See 15-Down
• Oxygen carrier
• It's found in veins
• Pigeon
• A bone of contention (with "bad")
• Patsy
• Wear down
• Luckless one
• Fir coat?
• Maple output
• Aphid's sustenance