Trema (plant)
Trema is a genus of evergreen trees closely related to the hackberries, occurring in subtropical and tropical regions of southern Asia, northern Australasia, Africa, South and Central America, and parts of North America. They are generally small trees, reaching tall.
Taxonomy
Previously included either in the elm family, Ulmaceae, or with Celtis in the Celtidaceae, genetic analysis has shown the Celtidaceae are best placed in the hemp family, Cannabaceae.Description
The leaves are alternate, simple, long, ovate-acuminate to lanceolate with a long pointed tip, and evenly serrated margins. The fruit is a small drupe in diameter.Species associations
Trema species are sometimes used as food plants by the larvae of hepialid moths of the genera Aenetus, including A. splendens, which burrow horizontally into the trunk then vertically down, and Endoclita, including E. malabaricus.Some Trema species unusually able to live in symbiosis with rhizobia for nitrogen fixation as a non-legume. In this case it is customary to mention these species as a separate genus Parasponia.
Uses
Trema orientale is widely planted for land reclamation in southern Asia, valued for its tolerance of poor soils due to its ability to fix nitrogen. It is also an invasive species on some Pacific Ocean islands.Species
Trema comprises the following species:- Trema andersonii Byng & Christenh.
- Trema angustifolium Blume
- Trema cannabina Lour. – type species - Lesser trema
- Trema cubense Urb.
- Trema discolor Blume
- Trema domingense Urb.
- Trema eurhynchum Byng & Christenh.
- Trema humbertii J.-F.Leroy
- Trema lamarckianum Blume – West Indian trema, Lamarck's trema
- Trema levigatum Hand.-Mazz.
- Trema melastomatifolium Byng & Christenh.
- Trema micranthum Blume – Jamaican nettle tree
- Trema nitidum C.J. Chen
- Trema orientale Blume – Pigeon wood
- Trema parviflorum Byng & Christenh.
- Trema politoria Blume
- Trema simulans Byng & Christenh.
- Trema tomentosum H.Hara – Poison peach
- * var. tomentosum H.Hara
- * var. viride Hewson – eastern Australia