Labrador Tea is a native perennial shrubby plant growing in wet areas from a rhizomatous root system. Stems are 1-1/2 to 3 feet long, erect to prostrate with smooth brown bark that sometime peels. Twigs and younger stems are covered with unicellular and multicellural hairs.
Leaves vary in shape from linear to ovate-lanceolate, up to 2 inches long and 1 inch wide, leathery, margins entire but usually turned under, pointed tip, the upper surface somewhat rough, the underside with dense hairs and scales. Leaf stalks also have the hairs. Leaves are fragrant when crushed and persist on the plant overwinter and the oldest are brown and pendant in the Spring.
The inflorescence is a semi-rounded cluster of 10 to 35 flowers with bracts beneath the cluster that are scaly or hairy. Flower buds are larger than leaf buds.
Flowers: Flowers are 5-parted. The corolla has 5 white or creamy-white petals, ovate, slightly broader above the middle, pointed tips, joined together only near their bases. The inside of the corolla is dense with uni-cellular hairs. There are usually 8 stamens with white filaments and very pale yellow anthers and a single style with a blunt tip. These are both exserted from the corolla. The calyx is very small with with 5 short lobes, all densely hairy. Flowers are considered fragrant and open after the new leaves form.
Seed: Fertilized flowers produce a longer than wide seed capsule elongated on both ends and containing up to 50 small seeds. The capsule is 3-5.5 × 4-6 mm in size and is on a recurved stalk; when the capsule is dry it slits upward from the bottom, releasing seeds to the wind. Flowers can self-fertilize but seed production is then lower than if insect pollinated.
Habitat: Labrador Tea is a plant preferring the acidic soils of bogs, swamps and wetlands of northern climate zones. It grows from a rhizome and a division of the root, or a sucker from the root is the best way to obtain new plants. Seeds should be planted in in fall or spring in moist peaty soil but not covered as they need light for germination. Plants must be in full sun to thrive. Encroachment by trees such as Tamarack and Black Spruce will gradually shade them out. Fires or burns that control tree species are adventitious to Labrador Tea.
Names: For many years Labrador Tea was classified as Ledum groenlandicum and while still in the Heath family, Ledum was used only for plants called Labrador Tea. Research has determined that these species should be in the genus Rhododendron. See FNA (Ref. #W7) for more details. The genus Rhododendron is the Greek name for the rose colored Oleander, derived from rhŏdŏn meaning 'a rose' and dĕndrŏn meaning 'a tree'. The species name, groenlandicum, means 'of Greenland', chosen by Oeder as explained below.
The author names for the plant classification are as follows: First to classify was ‘Oeder’ which refers to Georg Christian Edler von Oeder (1728-1791), German-Danish botanist, physician and economist. His most important publication, which contained this species, was Flora Danica in 1771; the work was planned to cover all of the species in the Danish crown lands, which at that time included parts of modern Germany, Norway and in the Atlantic - Iceland, the Faroe Islands and Greenland which explains the choice of species name for Labrador Tea.
The work of Oeder was amended in 1990 by two people: ‘Judd’ refers to Walter Stephen Judd (b. 1951), American botanist and taxonomist, Distinguished Professor in Botany at the University of Florida beginning in 2009, President of the American Society of Plant Taxonomists 2000-2001 and contributor to the Angiosperm Phylogeny Group. ‘Kron’ refers to Kathleen Anne Kron (b. 1956), American Botanist, Professor of Biology at Wake Forest University and manager of a lab working on the large-scale relationships between flowering plants and using the Ericaceae Family for a model.
Above: Labrador Tea has brownish woody stems with new growth at the top. Old leaves remain on the plant. Drawing from Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner's Sons, New York.
Below:- 1st photo - The inflorescence is a semi rounded cluster of stalked flowers, each flower with 5 petals. 2nd photo - the old leaves turn brown but hang of the plant after new leaves form.
Below:- - The new leaf has a short stalk and margins rolled over. The new twig and leaf stalk are densely hairy as is the leaf underside.
Notes: Labrador Tea is not indigenous to the Wildflower Garden. Eloise Butler brought in the first plants in 1913 from Gillett's Nursery, MA. She also planted it numerous other times: 1914, '18, '19(2x), '21, '23, '24(2x), '25, '27, '28, and '32. Martha Crone planted it in 1947, '50, and '55. It is no longer extant, but is found nearby in the Quaking Bog.
Labrador Tea in North America is found throughout Canada and in the United States only in the northern tier of states from Oregon in the west east across North Dakota to Minnesota, Wisconsin, Michigan, then Ohio and to the East Coast (absent from this group in Montana and Wyoming). It is widespread in Minnesota in the NE quadrant and North and East of a diagonal line from Washington and Hennepin Counties in the SE to Polk and Marshall in the NW. It is the only species of Labrador Tea in Minnesota but two others occur elsewhere in in North America. This is the only species of Rhododendron found wild in Minnesota.
Other species: R. columbianum, Western Labrador Tea, is found along the west coast from British Columbia down through California and into the adjoining mountain states. R. tormentosum, Trapper's Tea, is found in Canada, Alaska, Greenland, Europe and Asia.
Lore and uses: Labrador Tea leaves have long been used as a beverage before the introduction of Asian tea leaves. Stronger infusions have been used medicinally to treat irritations and a strong wash is said to kill lice (Ref. #7). Francis Densmore in her study of the Minnesota Chippewa (Ref. #5) wrote that they used it for tea by tying a packet of fresh leaves with a thin strip of Basswood and immersing in hot water. Dry leaves could be used if fresh were not available. Fernald (Ref. #6) wrote that in the more northern reaches of North America the leaves of L. palustre [now R. tomentosum] were superior to R. groenlandicum. Canadian explorer Dr. John Palliser (quoted in Fernald) wrote that the plant "makes a capital beverage in absence of a better." There are many write-ups about the uses of Labrador Tea. I copy here the pdf spec sheet from USDA which has a good summary.
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Identification booklet for most of the flowering forbs and small flowering shrubs of the Eloise Butler Wildflower Garden. Details Here.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"