Vitaceae, the Grape Family
Shrubs, climbing by tendrils or hold-fast roots, with palmately lobed or palmately compound leaves and small greenish flowers in panicles or flattened clusters; petals and sepals each 4 or 5; fruit a berry.
| 1a. Leaves compound (summer) (Virginia Creeper) — 2. | |
| 1b. Leaves simple (late spring) (Grape) — 4. | |
| 2a. Branches of the tendrils chiefly ending in adhesive disks — 3. | |
| 2b. Branches of the tendrils twining, or rarely with a few disks | Virginia Creeper, Psedera vitacea. |
| 3a. Stem and foliage glabrous | Virginia Creeper, Psedera quinquefolia. |
| 3b. Stem and foliage pubescent, at least when young | Virginia Creeper, Psedera quinquefolia var. hirsuta. |
| 4a. Leaves conspicuously pubescent beneath — 5. | |
| 4b. Leaves glabrous beneath when mature, or pubescent on the veins only — 6. | |
| 5a. A tendril or flower-cluster opposite each leaf | Fox Grape, Vitis labrusca. |
| 5b. No tendril opposite each third leaf | Summer Grape, Vitis aestivalis. |
| 6a. Pith continuous through the joints of the stem | Fox Grape, Vitis rotundifolia. |
| 6b. Pith interrupted by the solid joints — 7. | |
| 7a. Leaf-lobes with rounded angles between them | Summer Grape, Vitis bicolor. |
| 7b. Leaf-lobes with sharp angles between them — 8. | |
| 8a. Leaves coarsely toothed, unlobed or slightly 3-lobed | Frost Grape, Vitis cordifolia. |
| 8b. Leaves sharply toothed, prominently lobed | Frost Grape, Vitis vulpina. |