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Cornaceae
See list of 4 genera in this familyThe Cornaceae have seen a number of changes, including the inclusion of the Nyssaceae and the dismantling of the long familiar genus Cornus (accepted by some authors). Multiple studies have shown that Cornus can be confidently split into four (or more) groups worldwide that are morphologically and phylogenetically distinct (Fan and Xiang 2001, Xiang et al. 2006). Further supporting the recognition of these groups are patterns of hybridization (interspecific hybrids are restricted to within the genera recognized here). Three of the four genera are represented in New England. Cornus s.s. (Cornelian cherry) does not occur in the region.
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1a. Flowers with 5–8 petals, of 2 types—staminate with 8–15 stamens and functionally carpellate with 5–10 stamens that have nonfunctional anthers; pith diaphragmed; leaves alternate
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1b. Flowers with 4 petals, of 1 type—bisexual with 4 stamens; pith of woody species solid; leaves opposite, whorled, or alternate
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2a. Aerial stems herbaceous, 0.1–0.2 m tall, with whorled leaves (sometimes opposite at some nodes); petals terminated by awns; leaves strongly dimorphic, those of the lower nodes many times smaller than those of the upper node (+/- monomorphic in rare putative hybrid individuals); inflorescence pseudanthial, a corymb-like cyme subtended by 4 white, petaloid bracts
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2b. Aerial stems woody, 1–10 m tall, with opposite or whorled leaves; petals not awned at apex; leaves essentially monomorphic; inflorescence pseudanthial or not, with or without showy, petaloid bracts
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3a. Inflorescence pseudoanthial, with 4, white to yellow-white or pink, petaloid bracts [Fig. 593]; flowers sessile; petals green-white to yellow; fruits separate or fused together into a multiple, red; terminal flower bud large, globose or discoid
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Each photo represents one genus in this family.