Cornaceae, the Dogwood Family
Trees, shrubs, or herbs, with alternate leaves and small flowers in rather crowded rounded or flattened clusters; sepals 4, minute; petals and stamens each 4; ovary inferior, ripening into a berry. In one genus the flowers are minute and greenish, with 5 sepals and petals minute or none.
| 1a. Leaves alternate — 2. | |
| 1b. Leaves opposite — 3. | |
| 2a. Flowers white, conspicuous, in flattened clusters (shrubs 2-4 m. high; flowers in late spring) | Dogwood, Cornus alternifolia. |
| 2b. Flowers greenish, inconspicuous, in small axillary clusters (tree; flowers in spring) | Sour Gum, Nyssa sylvatica. |
| 3a. Flower clusters small and dense, surrounded by a showy involucre of 4 bracts, resembling a corolla of 4 petals — 4. | |
| 3b. Flowers in open flattened clusters, without petal-like involucre (shrubs 1-4 m. high; late spring) — 5. | |
| 4a. Herbaceous, 3 dm. high or less (flowers in late spring) | Dwarf Dogwood, Cornus canadensis. |
| 4b. Tall shrub or tree (flowers in late spring) | Flowering Dogwood, Cornus florida. |
| 5a. Leaves distinctly pubescent beneath with woolly or spreading hairs — 6. | |
| 5b. Leaves smooth beneath, or pubescent with short appressed hairs — 9. | |
| 6a. Leaves rough above; fruit white | Dogwood, Cornus asperifolia. |
| 6b. Leaves smooth or finely soft-hairy above — 7. | |
| 7a. Leaves at least twice as long as wide; branches brownish or purplish — 8. | |
| 7b. Leaves less than twice as long as wide; branches greenish; fruit blue | Dogwood, Cornus circinata. |
| 8a. Branches purplish; fruit blue | Dogwood, Cornus amomum. |
| 8b. Branches brownish; fruit white | Dogwood, Cornus baileyi. |
| 9a. Branches bright red or reddish-purple | Dogwood, Cornus stolonifera. |
| 9b. Branches grayish | Dogwood, Cornus paniculata. |