Leaves of Nyssa sylvatica in autumn.
Little known and still little used in our country (Spain), the tupelos (Nyssa), are deciduous trees that are highly valued in other countries for their magnificent autumnal colors. There are currently 8 species recognized in this genus, all with fairly high water requirements. The most commonly cultivated and with the largest distribution area (N. sylvatica and N. sinensis) are typical of wet and riverine forests. Others, such as N. aquatica, N. biflora or N. ogeche (all north american), are adapted to live in marshy areas and have a broad base very typical of the trees that grow in this type of environment, such as the bald cypress (Taxodium distichum) where they live together in many places. In our country (Spain) it is still rare to see them, although it is already possible to obtain N. sylvatica in some nurseries.
The tupelos flowers are not very flashy. These belong to N. sylvatica. / Picture: Using georgia native Plants
The genus Nyssa is another taxon with a disjoint distribution area at the continental level, with 5 species in eastern North America and 3 in East Asia. The genus, as might be expected, was also present on the European continent before the ice age, where different fossil species more or less related to the present species were described. As can be seen on the map, the most recent citations come from the Mediterranean basin (Middle Pleistocene) and the Caspian Sea region, where they seem to have survived until the last interglacial period (Eemian) in the river Emba delta. It really lacked them very little to survive on our continent.
Together with other small genera (Camptotheca, Davidia, Diplopanax, Mastixia), this genus constitutes the small family of Nyssaceae, related to the family of Cornaceae, in which they were still included in the APG III classification. Nisaceae, like most Cornales, still have primitive features such as free petals and arboreal size, which can also be observed in the neighboring order of the Ericales, for example.
| Nyssa | Family: Nyssaceae | Order: Cornales | |
Trees dioecious or functionally dioecious (with anthers of bisexual flowers that do not dehisce); bark gray brown, rough, ridged; twigs with transverse diaphragms; winter buds scaly. Leaves alternate, simple, often crowded near ends of branches, estipulate; petiole terete or winged; blade usually elliptic to oblanceolate or obovate, rarely ovate, base cuneate to rounded. Flowers unisexual, usually in heads or short racemes, in axil of a bract with 2 bracteoles; sepals forming a low rim; petals greenish to greenish white. Male flowers 5-merous, pedicelate or not. Stamens 10, arranged in two alternate whorls; filaments linear; anthers 2-celled, dorsifixed, with lateral lengthwise slits; disk pulvinate. Female flowers (4 or)5-merous, not pedicelate; staminodes usually present. Ovary inferior, 1(or 2)-loculed, 1-ovuled; style subulate or conic, bifid, with stigmatic tissue at inside of stylar arms. Fruit drupaceous, ± laterally flattened, with persistent calyx and disk, usually blue-black (sometimes reddish purple in N. aquatica; yellow, orange, or red in N. ogeche); mesocarp juicy, acidic. n = 22. Description: eFloras | |||
The only species that is occasionally cultivated in the Iberian Peninsula is Nyssa sylvatica which, however, is sensitive to frost when young and difficult to transplant. This makes it relatively rare and one has to go to arboretums or botanical gardens to observe it.
Nyssa sylvatica fruits / Picture: Great Plains Nursery
Author: Adrián Rodríguez
Translation: João Ferro
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