| Clue | Source | Date |
|---|---|---|
| Eucalyptus with a colorful name | ||
| Australian eucalyptus | Wall Street Journal | 11 Aug 2018 |
| Australian eucalyptus | ||
| Plywood source | Newsday | 22 Dec 2016 |
| Australian tree | The Times Concise | 25 Aug 2015 |
| Wood for railroad ties | ||
| Wood for railroad ties |