Flora of the Canadian Arctic Archipelago
English: Velvet bells,
French: Bartsie alpine.
Scrophulariaceae, Fernweed family.
Published in Sp. Pl. 602. 1753.
Vegetative morphology. Plants 5–20 cm high (to 30 cm high in Greenland); perennial herbs; caespitose, or not caespitose; glandular viscid (on the stems). Taproot present. Ground level or underground stems horizontal, or vertical. Caudex present (dark, stout, and scaly). Aerial stems erect. Aerial stem trichomes present; spreading. Leaves not heterophyllous; distributed along the stems; opposite; distinctly distichous; dying annually and non-persistent. Petioles absent. Leaf blade bases truncate, or rounded. Blades (5–)10–15(–20) mm long, (2.5–)4–8(–10) mm wide, spreading, ovate (broadly so at the base), flat, veins palmate. Blade adaxial surface glabrescent, hairs pubescent, hairs simple, hairs sparse, hairs white, or translucent. Blade abaxial surface glabrescent, hairs pubescent, hairs sparse, hairs white, hairs straight. Blade margins crenate, with non-glandular hairs (that are glabrescent), with 7–9 teeth on each side of the blade, with teeth toward the apex (and on the sides, but not at the base), with teeth per cm 7–9; degree of incision 5–10%; apices acute.
Reproductive morphology. Flowering stems squarish in cross section. Flowering stems with leaves. Flowering stems hairy. Flowering stems pubescent, or pilose. Flowering stem hairs simple; white or translucent; glandular hairs absent. Inflorescences spicate; lateral; diffuse; 2–6 cm long; elongating as the fruit matures. Pedicels absent. Floral bracts green (and purplish, small leaves, possibly interpreted as large floral bracts, subtend each flower). Flowers per inflorescence 3–12; medium-sized; bilaterally symmetrical (zygomorphic). Sepals conventional; 4; fused (below the middle); 5.5–6.6 mm wide; green, or purple (slightly). Calyx tubular; 4-lobed; hairy. Calyx hairs pubescent; glandular; white or translucent (when fresh), or brown (on herbarium specimens). Calyx margins ciliate. Petals conventional; fused; longer than the calyx; 4; purple; 1.3–1.8 mm long. Corolla bilabiate; 4-lobed. Stamens 4; fused to the corolla. Anthers yellow; 1.3–1.7 mm long. Ovary superior; carpels 2; syncarpous. Ovaries ovate, or inverse turnip-shaped; hairy. Styles 1; 8–16 mm long; straight. Stigmas per ovary 1. Placentation axile. Ovules per ovary numerous. Fruit sessile; with calyx persisting; dry; a capsule; ovoid (before splitting); straw-coloured; 8–12 mm long; 5–7 mm wide; hairy, or glabrescent; surface venation reticulate; dehiscent; splitting to the base into separate segments. Seeds numerous; 1.2–1.5 mm long; surfaces ridged, winged (with 3–4 prominent, almost frilly, ridges).
Chromosome information. 2n = 12, or 24, or 28, or 36, or 48.
(2n) (2x) = 12. Mattick in Tischler (1950, central Europe); Favarger (1953, central Europe);
(2n) (4x) = 24. Hambler (1954, Britain); Löve and Löve (1956, Iceland; 1982a, Arctic Canada);
Sokolovskaya and Strelkova (1960); Sorsa (1963b, Finland); Sokolovskaya (1970, northeastern Russia); Engelskjøn and Knaben (1971, Norway); Elkington (1974, Britain); Dalgaard (1988, western Greenland); Molau (1990). Numerous more southern counts.
(2n) = 28. Böcher and Larsen (1950, Europe);
(2n) (6x) = 36. Doulat (1946); Favarger and Küpfer (1968, central Europe);
(2n) (8x) = 48. Greilhuber (1971, central Europe?).
Löve and Löve (1975) accepted only the 2n = 24 plants as B. alpina s.s. It is unknown what they considered the other ploidy levels to be; the counts of the other numbers are also from areas where only B. alpina is recognised (Elven et al. 2003).
Ploidy levels recorded 2x, 4x, 6x, and 8x.
Ecology and habitat. Substrates: slopes; moderately well-drained areas; with high organic content. Sunny, grassy slopes (Porsild 1957). Growing on densely vegetated eastfacing slope near Ogac Lake, Frobisher Bay, Baffin Island (L. Gillespie, personal communication, 2001).
North American distribution. Nunavut Islands, northern Quebec, Labrador. Range in the Canadian Arctic Archipelago limited. Rare. Low Arctic, alpine. Arctic islands: Baffin.
Northern hemisphere distribution. Amphi-Atlantic. Northern Iceland, Northern Fennoscandian, KaninPechora, Polar Ural Novaya Zemlya, Labrador Hudson Bay, West Greenland, East Greenland.
General notes. Roots
Musselman and Rich (1976) found that in Iceland, B. alpina parasitises Carex species, Persicaria (Bistorta) vivipara, and almost certainly numerous other vascular plants. Haustoria are small in diameter (0.1 to 1.0 mm), have a reduced vascular core, and few (to 10) axial strands. Root hairs and a root cap are present on roots.
Nilsson and Svensson (1997) studied the host affiliation in Bartsia alpina and Pedicularis lapponica using visual examination of root connections and C14 labelling to identify host ranges of these two hemi-parasitic angiosperms. In total, 18 host species belonging to 11 families were found. Most of the hosts were members of the Cyperaceae. Both hemi-parasites formed connections with Pinguicula vulgaris, which has a very small and stunted root system compared with the root system of larger plants such as Betula species. The conclusion was that the mere presence of another species growing close to a hemi-parasitic plant does not mean that this plant is used as a host.
Bartsia alpina was one of the species in the Jonasson and Callaghan (1992) study of root mechanical properties related to disturbed and stressed habitats. They found the roots of dwarf shrubs and forbs had significantly higher resilience than graminoids and the highest tensile strengths. Forbs showed the lowest values for all of the measured variables except for resilience, which fell between the values of graminoids and dwarf shrubs.
Pollination and mating systems
Molau et al. (1989a), studying a northern Swedish population of B. alpina that is pollinated by bumblebees, found it to have a mixed mating system. Deposition of self-pollen did not occur without pollinator intervention, and outcrossing was further promoted by pollen carry-over, adaptive post-pollination floral changes, and by selective resource allocation to seeds resulting from cross-pollination. Multiple paternity apparently dominated in natural pollinations.
Kwak and Bergman (1996) observed the early flowers of B. alpina and the visitation by bumblebees in northern Sweden to find causes for low seed set in early flowers where bumblebees are the only visitors. They found that flowering of B. alpina started simultaneously with Astragalus frigidus, while Pedicularis lapponica was nearly out of flowers. Early blooming flowers of Bartsia received fewer visits than later blooming ones. The large volumes of nectar with a high sugar concentration in early flowers indicate that bumblebees neglect or fail to discover early blooming flowers of Bartsia. Early in the season seven bumblebees species visited Bartsia but later on Bombus pascuorum was dominant.
Molau (1991) studied genetic variation in Bartsia alpina for the maternal and paternal effects on seed size and reproductive success (RS) and assessed the impact of environmental factors in fertilisation and in defoliation experiments. Maternal effects on seed weight were much larger than paternal effects, and seed weight was also strongly influenced by resource availability (especially nitrogen). Defoliation experiments revealed an innate minimum seed weight, below which seed number was affected by resource deprivation. The reciprocal crossing program indicated a high level of gender specialisation in individual genets, ranging continuously from almost pure males to almost pure females.
Molau et al. (1989b) studied pre-dispersal seed predation in B. alpina in a northern Swedish population and found that it suffered high levels of pre-dispersal seed predation by larvae of two insect species, both specialists on rhinanthoid Scrophulariaceae hosts. The primary predator is Aethes deutschiana (epidoptera-Tortricidae), the host of which was previously unknown. The other predator is Gimnomera dorsata (Diptera-Scatophagidae), which is basically a Pedicularis specialist.
Cuendet et al. (1999) found B. alpina had three iridoid glucosides, two phenylpropanoid derivatives and one flavonoid in methanolic whole plant extract. These authors found that some of the compounds have radical scavenging activity against DPPH or antioxidant activity against beta-carotene on TLC bioassay.
Bergström and Bergström (1989) collected volatile compounds from the inflorescences of individual B. alpina plants in sub-alpine and alpine populations, and analysed them by gas chromatography and mass spectrometry. The compounds detected were alpha-pinene, Z-3-hexenol, Z-3-hexenyl acetate, phenyl acetaldehyde, and phenyl acetonitrile.
Illustrations. • Drawing of plant. Illustration of a Bartsia plant showing a well- developed rhizome. • Habitat: Baffin Island, Iqaluit. Plants with purple flowers growing near the markers, in the shelter of a cliff. Nunavut, Baffin Island, Ogac Lake. 15 July, 2004. Aiken and LeBlanc 04–097. CAN. • Habitat: Baffin Island, Ogac Lake. Plants with purple flowers growing near the markers, in the shelter of a cliff. Nunavut, Baffin Island, Ogac Lake. 15 July, 2004. Aiken and LeBlanc 04–097. CAN 586569. • Habitat in sedge meadow. Plants with purplish inflorescences growing in a sedge meadow. Nunavut, Baffin Island, Soper River, lappus site. Aiken 02–054. CAN. • Habitat under trees. Plant less than 15 cm high with purplish flowers and grey-green divaricate leaves, growing on a well-vegetated slope. Manitoba, Churchill, Northern Studies Centre. 22 July, 2001. Aiken and Brysting 01–001. CAN. Scale bar in cm. • Close-up of plant: Baffin Island, Ogac Lake. Plant with simple, sessile, opposite (divaricate) leaves and a capitate inflorescence of deep purple flowers. Aiken and LeBlanc 04–097. CAN 586569. • Close-up of inflorescences. Plant with divaricate leaves and spicate inflorescences in which most of the flowers are going to seed. Note the purplish leaves subtending a flower, the still attached greenish purple hairy calyx, the green hairy ovaries, and the long styles. Manitoba, Churchill, Northern Studies Centre. 22 July, 2001. Aiken and Brysting 01–001. • Close-up of inflorescence. Inflorescence of bilabiate flowers. Note the lower right-hand flower with style and stigma protruding. Aiken and LeBlanc 04–097. CAN 586569. • Close-up of flower. Bilabiate flower with three deep magenta lower petals that are recurved at the tips and ciliate on the margins. The upper hooded petals are also ciliate and there is a cluster of four yellow anthers. Aiken and Brysting 01–001. CAN. • Arctic Island Distribution.
This publication is available on the internet (posted May 2011) and on CD-ROM (published in 2007). These versions are identical in content, except that the errata page for CD-ROM is accessible on the main index page of the web version.
Recommended citation for the web-based version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. NRC Research Press, National Research Council of Canada, Ottawa. http://nature.ca/aaflora/data, accessed on DATE.
Recommended citation for the CD-ROM version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. [CD-ROM] NRC Research Press, National Research Council of Canada, Ottawa..