''Trevoa'' is a genus of actinorhizal plants; these

dicotyledon The dicotyledons, also known as dicots (or, more rarely, dicotyls), are one of the two groups into which all the flowering plants (angiosperms) were formerly divided. The name refers to one of the typical characteristics of the group: namely, t ...

flora are trees or small shrubs. The genus was first proposed by Miers in 1825, but was not fully described until 1830 by Sir

William Jackson Hooker Sir William Jackson Hooker (6 July 178512 August 1865) was an English botanist and botanical illustrator, who became the first director of Kew when in 1841 it was recommended to be placed under state ownership as a botanic garden. At Kew he ...

. Genus members are notable for their ability to fix nitrogen. Species of this genus are generally found in the near coastal forests and arid

shrubland Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It m ...

of South America. Some species are localized in the mountains of central Chile; for example, the species ''

Trevoa trinervis ''Retanilla trinervia'' is a species of actinorhizal plant within the family Rhamnaceae; this dicotyledon flora is a shrub or small tree. ''R. trinervia'' is notable for its ability to fix nitrogen. This species mainly occurs in the near coastal ...

'' occurs in the La Campana National Park and other proximate areas of central Chile. Along with some related plants in the family

Rhamnaceae The Rhamnaceae are a large family of flowering plants, mostly trees, shrubs, and some vines, commonly called the buckthorn family. Rhamnaceae is included in the order Rosales. The family contains about 55 genera and 950 species. The Rhamnaceae h ...

, they fix nitrogen via

root nodule Root nodules are found on the roots of plants, primarily legumes, that form a symbiosis with nitrogen-fixing bacteria. Under nitrogen-limiting conditions, capable plants form a symbiotic relationship with a host-specific strain of bacteria known a ...

s which contain '' Frankia'' bacteria. Other nitrogen-fixing genera in this family include ''

Ceanothus ''Ceanothus'' is a genus of about 50–60 species of Actinorhizal plant, nitrogen-fixing shrubs and small trees in the buckthorn family (Rhamnaceae). Common names for members of this genus are buckbrush, California lilac, soap bush, or just ceano ...

'', ''

Colletia ''Colletia'' is a genus of flowering plants in the family Rhamnaceae, with five species of spiny shrubs. All species of this genus are native to southern South America. They are non-legume nitrogen fixer Actinorhizal plants are a group of angios ...

'', ''

Discaria ''Discaria'' is a genus of 6 species of flowering plants in the family Rhamnaceae, native to temperate regions of the Southern Hemisphere, in Australia, New Zealand and South America. They are deciduous thorny shrubs or small trees growing to 2 ...

'', ''

Kentrothamnus ''Kentrothamnus'' is a monotypic genus of flowering plants in the family Rhamnaceae, native to Bolivia and Argentina. The only species is ''Kentrothamnus weddellianus''. It is an actinorhizal plant Actinorhizal plants are a group of angiosperms ...

'', and '' Retanilla''.

Taxonomy

The botanist Karl Friedrich Reiche, publishing in the years 1894–1911, recognized 6 species. Currently there are five recognized species in the genus.

Species

''Trevoa'' comprises the following species: * '' Trevoa campanulata'' Reiche * '' Trevoa closiana'' Miers * '' Trevoa glauca'' Reiche * '' Trevoa quinquenervia'' Gillies & Hook. (syn. ''Talguenea quinquenervia'') * '' Trevoa spinifer'' Escal.

Species names with uncertain taxonomic status

The status of the following species and hybrids is unresolved: * ''Trevoa berteroniana'' Steud. * ''Trevoa tenuis'' Miers

Formerly placed here

* ''Trevoa trinervis'' Miers = ''

Retanilla trinervia ''Retanilla trinervia'' is a species of actinorhizal plant within the family Rhamnaceae; this dicotyledon flora is a shrub or small tree. ''R. trinervia'' is notable for its ability to fix nitrogen. This species mainly occurs in the near coastal ...

'' (Gillies & Hook.) Hook. & Arn.

Notes

References

* C. Michael Hogan. 2008
''Chilean Wine Palm: Jubaea chilensis'', GlobalTwitcher.com, ed. N. Stromberg
* J. Miers. 1860. ''The Annals and Magazine of Natural History: Including Zoology, Botany, and Geology'', Published by Taylor and Francis, ser.3: v.5, p 487 Rhamnaceae Rhamnaceae genera {{Rhamnaceae-stub