Sagina subulata (heath pearlwort,Irish-moss,awl-leaf pearlwort or Scottish moss; syn. Sagina pilifera auct. non (DC.) Fenzl) is a species of Sagina, native to Europe, from Iceland south to Spain, and east to southern Sweden and Romania. It occurs on dry sandy or gravelly soils.
Heath pearlwort is a low-growing prostrate perennial plant forming a thick, dense mat with stems less than 10 cm long, and slender subulate (awl-shaped) leaves up to 1 cm long. The flowers are 4-5 mm diameter, with five white petals the same length as the green sepals; they are produced singly on erect stems 2-4 cm long. The seeds are smooth, brown, triangular shaped, 0.4-0.5 mm, produced in a capsule 2.5-3 mm long.
There are two varieties, Sagina subulata var. subulata with glandular-hairy sepals, and Sagina subulata var. glabrata Gillot with hairless sepals; the latter is often a lawn weed, and has been confused with the related Mediterranean species Sagina pilifera. The cultivar 'Aurea' (referred to as Scottish or Scotch Moss in the horticultural trade) is grown as a garden plant.
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