Labrador tea

Close up of a Labrador Tea flower, found in the alpine zone of northern New Hampshire.

Ledum latifolium, an earlier name for Rhododendron groenlandicum

Labrador tea is a common name for the three closely related plant species and the name of an herbal tea made from the plants:

All three species are primarily wetland plants in the heath family. The herbal tea has been a favorite beverage among Athabaskan and Inuit people.

Description

All three species used to make Labrador tea are low, slow-growing shrubs with evergreen leaves:

• Rhododendron tomentosum (Northern Labrador tea, previously Ledum palustre),
• Rhododendron groenlandicum, (Bog Labrador tea, previously Ledum groenlandicum or Ledum latifolium) and
• Rhododendron neoglandulosum, (Western Labrador tea, or trapper's tea, previously Ledum glandulosum).

The leaves are smooth on top with often wrinkled edges, and fuzzy white to red-brown underneath.^[1]

Uses

The Athabaskans brew the leaves as a beverage. Others use Labrador tea to spice meat by boiling the leaves and branches in water and then soaking the meat in the decoction.^[1] The Pomo, Kashaya, Tolowa and Yurok of Northern California boiled the leaves of Western Labrador Tea similarly, to make a medicinal herbal tea.^[2] In Greenland, this is still the case. During the 18th century, German brewers used R. tomentosum while brewing beer to make it more intoxicating, but became forbidden because it led to increased aggression.^[1]

Toxicology

There is no sufficient data that demonstrates Labrador tea is safe to consume as toxicity varies across species and localities. Excessive consumption is not recommended due to diuresis, vomiting, dizziness, and drowsiness.^[1] Large doses can lead to cramps convulsions, paralysis, and in rare cases death.^[1]

Toxicity occurs due to terpenoid ledol found in all Labrador tea species. R. groenlandicum has the lowest toxicity due to lower levels of ledol. Grayanotoxins are also present, but few lethal human cases of poisoning due to grayanotoxins in Labrador tea have been documented. However, lethal poisonings have been documented in livestock.^[1]

Habitat

R. tomentosum grows in peaty soils, shrubby areas, moss and lichen tundra.

R. groenlandicum grows in bogs and wet shores, and sometimes on rocky alpine slopes. Both species are generally northern (north temperate to tundra) in distribution, with the range of R. groenlandicum somewhat farther south.

R. neoglandulosum grows in wetlands and bogs in western North America, from British Columbia to California to Colorado.

All three species can be found in wetlands and peat bogs.^[1]

Harvesting

Labrador tea is slow growing, so new single leaves are collected in spring from multiple plants to avoid damaging individual plants every other year.^[1]

References

1. 1 2 3 4 5 6 7 8 Dampc, A.; M. Luczkiewicz (2015). "Labrador tea – the aromatic beverage and spice: a review of origin, processing and safety". Journal of the Science of Food and Agriculture 95: 1577–83. doi:10.1002/jsfa.6889. PMID 25156477. 
2. ↑ Native American Ethnobotany Database for Ledum glandulosum