- Name also: Common Saw-wort, Alpine Sawwort, Snow Lotus
- Family: Daisy Family – Compositae, subfamily Carduoideae
(formerly Aster Family – Asteraceae)
- Growing form: Perennial herb.
- Height: 10–60 cm (4–25 in.). Stem branchless, short-haired, usually reddish brown.
- Flower: Single flower-like 1.5–2 cm capitula surrounded by involucral bracts. Capitula’s ray-florets lacking; disc florets bluish violet (occasionally white), tubular. Stamens 5, longer than corolla, blue. Pistil of 2 fused carpels. Involucre cylindrical, woolly when young, becoming glabrous, involucral bracts overlapping in many rows, reddish brown–greyish brown, shiny-haired. Capitula in dense clusters of 4–12. Flowers with vanilla fragrance.
- Leaves: Alternate, basal leaves long-stalked, stem leaves stalk winged, uppermost leaves stalkless. Blade lanceolate, with tapered base, long-tapered, sparsely toothed–entire, with wavy margin, top dark green, often partly purple, underside greyish-haired.
- Fruit: Cylindrical, glabrous, 4 mm (0.16 in.) long achene, tip with unbranched hairs.
- Habitat: Fens, rich swamps, bogs and meadows, springs, stream banks, rich mountain birch woodland, fell meadows. Calciphile.
- Flowering time: July–September.
Alpine saw-wort’s genus has been named in honour of the Swiss botanist Théodore de Saussurea, who was the first to realize that green plants need carbon dioxide. Alpine saw-wort must assimilate carbon dioxide, water and sunlight, and in its southern habitat it also needs calciferous soil. In the forest zone it is a demanding fen species which grows around Kuusamo, Kittilä and Keminmaa–Tervola in very nutritious places only. In the fell region, however, alpine saw-wort is very common in all kinds of places: moors, broad-leaved forests, tall-growing meadows, stream-banks, coasts and bogs and even over a kilometre (0.6 miles) above sea level. The Finnish alpine saw-wort population is probably descended from plants that spent the Ice Age on the ice-free Norwegian coastal fells, and that is why it is found mainly in the north.
Alpine saw-wort blooms late, not until the end of the summer. On tundra it only flowers during exceptionally favourable years, but the fell population is complemented by plants from lower slopes where the plants can flower more often. There are not many flowers in the capitula but they have beautifully-coloured corollas and stamens which makes them look very attractive. Their fragrance has been compared to vanilla, like Lapland lousewort and twin flower.
Alpine saw-wort looks like a thistle but it is completely spineless. When it is not flowering it looks like melancholy thistle (Cirsium helenioides), which also grows in the tundra area, usually only as a leaf rosette. Both of the plants have two-tone leaves with a green upper side and a grey or virtually white underside. Alpine saw-wort’s leaf margins are densely toothed and the blade continues into the stem as a gradually narrowing wing.