This mat-forming perennial was naturalised on waste ground near the railway station at Tenby (Pembs.), and occurs elsewhere as a casual on walls, railway banks, roadsides and in chalk pits. Lowland.
A perennial herb of grassy habitats on well-drained soils, favouring those which are calcareous or otherwise base-rich, but also on acidic sands. It occurs on grazed and ungrazed chalk and limestone downs, in rough pasture and other grassland, in woodland edges and open rides; less frequently on roadsides and rough ground. Generally lowland, but reaching 810 m on Snowdon (Caerns.) and Dollywagon Pike (Westmorland).
A perennial herb usually found by the side of mountain streams, in open stony flushes on gently- or steeply-sloping ground, or sprawling over wet rocks; less commonly, on wet screes and sand dunes. It may rapidly colonise disturbed soil, such as newly dug cuttings on forestry tracks, in the vicinity of natural habitats. Whilst not strictly a calcicole, it avoids the most base-poor substrates. 0-1175 m (Breadalbanes, Mid Perth).
A perennial, bulbiliferous herb of basic rocks. It grows in crevices and beneath overhangs where exposure is limited and humidity is high, usually in sites with late snow-lie. S. cernua flowers only infrequently, and, apparently, seed is not set in Britain; vegetative reproduction is by axillary bulbils. From 920 m (Bidean nam Bian, Main Argyll) to 1170 m (Ben Lawers, Mid Perth).
A cushion-forming, perennial herb of well-drained base-rich rocks. It is found on mossy ledges, in crevices and on boulder-scree slopes. It appears to be highly susceptible to drought. From 520 m (Cwm Idwal, Caerns.) to 1180 m (Ben Nevis, Westerness).
A stoloniferous perennial with basal leaf rosettes occurring as a naturalised garden escape on rocks and old walls, or as a casual throw-out on rubbish tips. Lowland.
An annual, possibly sometimes biennial, herb, occurring in damp, usually shaded habitats such as at the foot of walls and on old rockeries. Setting abundant seed, the plant reproduces readily and can become a weed in gardens and nurseries. Lowland.
A perennial herb with a bulbiliferous rhizome, growing in moist but well-drained, often lightly grazed, base-rich and neutral grassland, in unimproved pastures and hay meadows, and on grassy banks. More rarely, it occurs on shaded river banks and in damp woodland. It is also locally naturalised near houses and in churchyards. Generally lowland, but reaching 580 m N.E. of Helbeck Fell (Westmorland).
A stoloniferous perennial herb found in wet, base-rich flushes and mires, especially where the vegetation is checked by grazing. Formerly near sea level, it survives now only in its upland localities usually at 300-650 m, but reaching 750 m (Mickle Fell, N.W. Yorks.).
A perennial, stoloniferous herb, found growing only in damp, shaded places, such as woods, N.-facing cliffs and banks, and by streams and on rocks in the mountains. Naturalised populations in Britain, often derived from garden escapes, are often found on limestone, whereas in its native Ireland the species occurs only on siliceous rock. 0?915 m (Mt Brandon, S. Kerry).