1. Betula nigra   birch   cedar   hibiscus   spruce   Hint Half-n-half Clue   2. Juglans nigra   walnut   maple   pine   ash   Half-n-half Clue   3. Juniperus virginiana   maple   cedar   pine   hibiscus   Half-n-half Clue   4. Hibiscus lasiocarpus   spruce   hickory   hibiscus   oak   Half-n-half Clue   5. Acer rubrum   spruce   maple   hickory   ash   Half-n-half Clue   6. Platanus occidentalis   ash   spruce   sycamore   oak   Half-n-half Clue   7. Carya ordorata   walnut   cedar   hickory   sycamore   Half-n-half Clue