Stems: erect or ascending, the bractlets rusty-tomentose. Leaves: oblong, obtuse, green and slightly rugose above, densely tomentose beneath, the wool soon ferruginous, and the margins strongly revolute. Flowers: umbellate or corymbose, numerous, terminal; petals five, spreading; pedicels brown-canescent, recurved in fruit.
This lovely flowering shrub thrives chiefly on low-lying flats and in wet marshy places, where its large terminal clusters of snow-white blossoms grow abundantly from sticky scaly buds on the low bushes. The foliage of the Woolly Labrador Tea is strictly characteristic, for the leaves are long-shaped, with revolute margins, green and slightly wrinkled on the top and densely woolly underneath, the wool in the developed foliage being the colour of iron rust. This thick woolly growth is probably designed for the express purpose of protecting the pores of the leaves from becoming clogged by the moist vapours that must necessarily rise round about them, owing to the extremely wet ground in which the shrubs flourish. Plants that grow in very damp localities are specially dependent upon the free perspiration of their leaves to throw off the vast quantities of moisture they absorb through their roots and stems; consequently such marsh shrubs as the Labrador Teas are forced to adopt a regular system in order to prevent the pores of their leaves from becoming so congested with moisture from outside that they cannot perform their legitimate function of throwing off the moisture from within. The small branches are also covered with red, rusty, wool-like hairs.
The flower-clusters are very beautiful, each individual blossom consisting of five pure white petals, with a large green ovary set in the centre; the style and numerous long stamens are very conspicuous. Both the flowers and leaves have a strong aromatic fragrance.
Ledum glandnlosum, or Smooth-leaved Labrador Tea, has also long-shaped, thick, leathery leaves of a brownish-green hue, but they are not woolly underneath, being quite smooth on both sides, though slightly white and resinous below. The flower-clusters closely resemble those of L. groenlandiaim.
The name Labrador Tea is derived from the fact that many old settlers, and also campers and lumbermen in the backwoods, formerly used in place of tea a decoction brewed from the aromatic leaves of this shrub.