''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 n ...

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, which ...

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

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 nativ ...

, subgenus ''

'', of the genus ''

''.

Description

''Ledum'' species often grow together with poisonous plants such as

bog-laurel ''Kalmia polifolia'', previously known as ''Kalmia glauca'' and commonly called bog laurel, swamp laurel, or pale laurel, is a perennial evergreen shrub of cold acidic bogs, in the family Ericaceae. It is native to north-eastern North America, ...

and bog-rosemary, 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 Genetic may refer to: *Genetics, in biology, the science of genes, heredity, and the variation of organisms **Genetic, used as an adjective, refers to genes ***Genetic disorder, any disorder caused by a genetic mutation, whether inherited or de nov ...

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

hybrid Hybrid may refer to: Science * Hybrid (biology), an offspring resulting from cross-breeding ** Hybrid grape, grape varieties produced by cross-breeding two ''Vitis'' species ** Hybridity, the property of a hybrid plant which is a union of two diff ...

s ( nothospecies) also occur. *''Ledum columbianum'' = ''Rhododendron'' × ''columbianum'' (''R. groenlandicum'' × ''R. neoglandulosum'') is listed by Harri Harmaja as a natural hybrid. *''

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

'' Abromeit is a probably hybrid between ''Ledum palustre'' subsp. ''decumbens'' and ''

Rhododendron lapponicum ''Rhododendron lapponicum'' (高山杜鹃), the Lapland rosebay, is a dwarf rhododendron species found in subarctic The subarctic zone is a region in the Northern Hemisphere immediately south of the true Arctic, north of humid continental ...

''.

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 f ...

. 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 Flora of Alaska Herbs Herbal tea Plant subsections