''Ledum'' was a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Ericaceae The Ericaceae are a family of flowering plants, commonly known as the heath or heather family, found most commonly in acidic and infertile growing conditions. The family is large, with c.4250 known species spread across 124 genera, making it th ...

, including 8 species of

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, whic ...

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from tree ...

s native to cool temperate and subarctic regions of the

Northern Hemisphere The Northern Hemisphere is the half of Earth that is north of the Equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's Nort ...

and commonly known as Labrador tea. It is now recognised as a subsection of section

Rhododendron ''Rhododendron'' (; from Ancient Greek ''rhódon'' "rose" and ''déndron'' "tree") is a very large genus of about 1,024 species of woody plants in the heath family (Ericaceae). They can be either evergreen or deciduous. Most species are nati ...

, subgenus ''

'', of the genus ''

''.

Description

''Ledum'' species often grow together with poisonous plants such as bog-laurel and

bog-rosemary ''Andromeda polifolia'', common name bog-rosemary, is a species of flowering plant in the heath family Ericaceae, native to northern parts of the Northern Hemisphere. It is the only member of the genus ''Andromeda'', and is only found in bogs in ...

, but certain species (e.g. '' L. groenlandicum'' and '' L. palustre'') are easily distinguished by the distinctive rust coloured fuzz on the bottom of leaves.

Taxonomy

Reclassification into Rhododendron

Recent genetic evidence has shown that the species previously treated in this genus are correctly placed in the genus ''

'', where they are now treated as ''Rhododendron'' subsect. ''Ledum''. Because some of the species names used in ''Ledum'' could not be used in ''Rhododendron'' (the names already having been used for other species already in this large genus), new names had to be coined for them.

Species

The species listed in genus ''Ledum'' (accepted and synonyms), with their current accepted names are:

Species References

Ledum Rhododendron Other

Hybrids

Natural hybrids ( nothospecies) also occur. *''Ledum columbianum'' = ''Rhododendron'' × ''columbianum'' (''R. groenlandicum'' × ''R. neoglandulosum'') is listed by Harri Harmaja as a natural hybrid. *'' Rhododendron vanhoeffeni'' Abromeit is a probably hybrid between ''Ledum palustre'' subsp. ''decumbens'' and '' Rhododendron lapponicum''.

Uses

Some species (e.g. ''L. groenlandicum'') have been used to produce

Labrador tea Labrador tea is a common name for three closely related plant species in the genus ''Rhododendron'' as well as an herbal tea made from their leaves. All three species are primarily wetland plants in the heath family. The herbal tea has been a ...

. Other species have varying levels of toxicity (e.g. ''L. glandulosum''). Evergreen Labrador Tea grows slowly, but retains its leaves year-round. Users should take care not to over-harvest leaves from any single plant.

Notes

References

Bibliography

* * * * * * * {{Taxonbar, from=Q21389473

Ledum ''Ledum'' was a genus in the family Ericaceae, including 8 species of evergreen shrubs native to cool temperate and subarctic regions of the Northern Hemisphere and commonly known as Labrador tea. It is now recognised as a subsection of section R ...

Flora of Alaska Herbs Herbal tea Plant subsections