Ericaceae A.L. de Jussieu
Ericaceae, bilberry family.
Vegetative morphology. Plants shrubs; dwarf shrubs, or low shrubs; 1–20(–45) cm high; with evergreen or deciduous leaves. With fibrous roots developed along the prostrate stems. Aerial stems erect, or ascending, or prostrate; glabrous, or sparsely hairy; stem hairs appressed, or spreading (if applicable). Branches epidermis not flaky (usually), or flaky (Arctous). Leaves distributed along the stems; alternate; distinctly distichous, or not distinctly distichous; simple; evergreen, existing for a single season or less, and marcescent. Stipules absent. Petioles present, or absent; 0.1–5 mm long (if applicable); glabrous, or hairy. Petioles hairs appressed, or spreading, or reflexed; curved. Leaf blade bases truncate, or acute, or attenuate. Blades 1–15(–55) mm long; 1–10(–30) mm wide. Blades appressed to the stem, or spreading, or divaricate, or reflexed; leathery (usually), or herbaceous; linear, or oblong, or elliptic, or lanceolate, or ovate, or oblanceolate, or obovate; circular in cross section, or flat, or involute, or revolute; veins pinnate, or appearing single-veined, or with inconspicuous veins, or veins reticulate. Blades adaxial surface dull (usually), or shiny; with sessile glands (Rhododendron), or without sessile glands (usually); glabrous. Blades abaxial surface with sessile glands, or without sessile glands; glabrous, or hairy. Blades abaxial surface hairs very dense (if applicable). Blades abaxial surface pubescent, or tomentose. Blades abaxial surface hairs white, or translucent hairs, or rust-colored hairs; straight, or curved, or wavy; appressed, or spreading, or erect. Blade margins entire, or glandular-dotted, or serrulate; glabrous (usually); with teeth all around the blade, or toward the apex. Leaf apices acuminate, or acute, or obtuse, or rounded, or retuse.
Reproductive morphology. Flowering stems absent. Flowers solitary, or in inflorescences. Inflorescence fasciculate (with a few flowers), or an umbel (Ledum); axillary (often towards the ends of the branches). Pedicels present, or absent (often, subsessile). Pedicels bract leaves 1–30 mm long. Flowers small, less than 5 mm in diameter or length (usually), or medium-sized, 5–15 mm in diameter or length (Rhododendron). Floral bracts apex entire, or lacerate and obtuse. Calyx sepals 5; free, or fused; 0.5–3 mm long; 0.5–1.5 mm wide (if applicable). Calyx green, or yellow, or brown, or red, or black; with sessile glands, or without sessile glands; glabrous, or hairy. Calyx hairs brown. Petals fused (usually), or free (Ledum); 5; green, or white, or yellow, or pink, or purple; 3.5–12 mm long. Corolla rotate, or campanulate, or urceolate, or funnel-form; 5-lobed (if applicable). Stamens 8–10. Anthers purple, or reddish, becoming yellow, or yellow; 0.4–2.2 mm long. Nectaries present. Gynoecia superior. Carpels syncarpous; (3–)5. Ovaries ovate, or inverse turnip-shaped, or oblong, or subglobose; glabrous, or hairy, or with sessile glands. Styles 1. Placentation axile. Ovules 5 (, Arctostaphyllos or numerous). Fruit sessile, or stalked. Fruit with calyx persisting; fleshy, or dry; a capsule, or a berry; spherical, or ovoid, or conical; not distinctly flattened; teeth 5. Fruit (1.5–)2–10 mm long; (1.5–)2.5–10 mm wide; yellowish, or black, or brown, or red, or blue; glabrous (covered with papillae Ledum); surface venation reticulate, or appearing veinless.
Illustrations. • Arctostaphylos alpina. Arctostaphylos alpina. Bright red autumn leaves, and black fruit, 6–8 mm in diameter, that distinguishes this species from Arctostaphylos rubra. Inunavut, Baffin Island, Iqaluit, Plants growing on hillside behind town, 27 Aug. 1997, Aiken 97–048. CAN. • Arctostaphylos rubra. Arctostaphylos rubra. The ripe fruit of Red bearberry is a bright red berry. Note also the crenulate leaf margins. Aiken and Anne Brysting 01–481. • Casiope tetragona. Casiope tetragona. Zone of heather in flower. Plants growing on frost boil tundra towards the base of a pingo. N.W.T., Banks Island in Aulavik National Park, beside Thomsen River. 11 July, 1999. Aiken. SA99–049. CAN. Scale bar in cm. • Harrimanella hypnoides. Plant with conspicuously narrow, simple, overlapping leaves. Flowers are borne singly on pedicels. Petals that are white when fresh have faded to yellow. The sepals are reddish sepals. Developing fruit capsule at right. 26 Aug. 1961. Nunavut, island SSW of Broughton Island, Baffin Island. N.G. Smith, VP-125–61. • Ledum palustre subsp. decumbens. Ledum palustre subsp. decumbens. Facing in the uppermost left hand flower are two free, overlapping petals. The whorl of anthers alternate with the petals is at anthesis, an inner whorl of anthers that are alternate with the petals are shorter and pre-anthesis. The style is shorter than the petals and the stigma is not yet receptive. Compare with the bell-shaped fused petals of the lowermost flowers of Cranberry (Vaccinium vitis-idaea) which is growing below. Leaves of Sorrel (Oxyria digyna) in the lower right hand corner. Photo by Lynn Gillespie. • Loiseleuria procumbens. Flowers (about 7 mm in diameter) have 5 pink, fused petals and 5 red pre-anthesis stamens) in a single whorl alternate with the petals. There are reddish developing capsules. The leathery leaves have a single prominent vein sunk into the adaxial surface. Nunavut, Baffin Island, Frobisher Bay, Ogac Lake. L.L. Consaul, L.J. Gillespie, and R.J. Soreng 2362a. 16 August. • Phyllodoce caerulea. Semi-prostrate shrub with branching woody stems, densely overlapping divariacate, linear, leathery, leaves 4–8 mm long, flowers with deep red, mostly free sepals and pink petals fused into a tubular corolla with 5 tiny lobes. Nunavut, Baffin Island, Iqaluit, J.M. Gillett, 18971, 10 July, 1982. CAN 466153. • Rhododendron lapponicum. Conspicuous purplish-pink flowers (5-)10–15 mm in diameter borne in groups of 2–4. Plants growing in a dense low Arctic tundra with Dryas, willow, Carex and Bilberry, on rocky hillside, Nunavut, Baffin Island, north of Iqaluit 19 July 1982, J.M. Gillett 18959. CAN. • Vaccinium uliginosum. Vivid blue berry, 10–15 mm round formed from an ovary with 5 carpels, the tops of which appear as teeth on the top of the berry. The style is still attached and shows the small capitate stigma. Note the glabrous leaves with reticulate venation. Nunavut, Baffin Island, at Iqaluit. Aiken 97–047. CAN. • Vaccinium vitis-idaea. Shiny red fruit 6–9 mm in diameter. At the apex of the fruit the position of the five carpels in the ovary is outlined. Nunavut, Baffin Island, at Iqaluit. Aiken 97–046. CAN.
Cite this publication as: ‘S.G. Aiken, M.J. Dallwitz, L.L. Consaul, C.L. McJannet, L.J. Gillespie, R.L. Boles, G.W. Argus, J.M. Gillett, P.J. Scott, R. Elven, M.C. LeBlanc, A.K. Brysting and H. Solstad. 1999 onwards. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 29th April 2003. http://www.mun.ca/biology/delta/arcticf/’. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).
