Related Clues:
- McCullough's ''The ___ Birds''
- Prickle
- Prickly plant part
- Gum-yielding tree
- Locust tree, e.g.
- Irritant in one's side?
- Small mimosa-family tree
- Gum arabic
- Annoyance, so to speak
- Cause of some sticker shock?
- Tree source of gum
- Gum arabic source
- Gum arabic-yielding tree
- Metaphorical cause of discomfort
- Cause of a sore spot