Sphagnum Fallax S
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Sphagnales Sphagnum fallax S. recurvum var. mucronatum, S. brevifolium, S. isoviitae Flat-topped Bog-moss Section Cuspidata Stem leaf 0.5 mm Detail of stem leaf tip 5 mm Identification Medium-sized, green to mustard-brown, growing in carpets. Male plants may have a contrasting darker tip to the capitula and spreading branches. Capitula are convex and usually stellate, with developing branches in neat pairs, obvious between the capitula rays. Branch leaves are weakly to clearly in straight lines. Spreading and pendent branches are well-differentiated; the pendent branches are almost white, appressed to and hiding the stem, about as long as or shorter than the spreading branches. The stem leaf is more or less triangular, as long as wide, or a little longer (length less than 1.5 times the width), with a sharply pointed tip that has a minutely pinched apex. When dry, spreading branch leaves are conspicuously recurved. Capsules are occasional. Similar species S. fallax is the commonest of the three species into which S. recurvum of earlier Floras has been divided, the other two being S. angustifolium (p. 307) and S. flexuosum (p. 308). Stem leaves in all three are closely appressed to the stem, and can be difficult to see. It is important to obtain a clear view of several stem leaves, so as to reliably assess the shape of the tip. Plants with stem leaves clearly pinched at the tip are S. fallax. If the stem leaf appears at all rounded, fringed or notched at the tip, it is likely to be S. angustifolium or S. flexuosum. Terrestrial, stellate forms of S. cuspidatum (p. 302) look superficially similar, but its stem leaf is more acutely pointed and much longer than wide, there is only 1 (less neat-looking) juvenile branch between the capitulum rays (or none discernible) and leaves at the end of spreading branches are curved. Also see the very rare S. balticum (p. 304). Habitat Very common in a wide range of permanently damp or wet habitats, including nutrient-poor to intermediate fens, and pools and runnels on bogs. 306 Photo David Holyoak Drawings Sharon Pilkington Text Andy Amphlett & Sandy Payne Sphagnales Sphagnum fimbriatum Fringed Bog-moss Section Acutifolia 4 mm Stem leaf 1 mm 4 mm Identification Grows as slender, elongated stems, forming loose carpets or soft hummocks. It is all green, apart from the end of male branches which can be brownish; there is never any trace of red or pink. Capitula are small, with a very conspicuous terminal bud. Branches are very long and thin. Stem leaves are fan-shaped, often wider than long, and narrowest at or near the base, forming a more or less complete, stiff, erect ruff around the stem (obvious when capitulum is removed), fringed around the whole upper margin and slightly down the sides. Capsules are common, often abundant. Similar species More likely to be overlooked than misidentified, as at a casual glance it might be mistaken for a green, etiolated form of a number of species. The very prominent terminal bud, limp appearance and common presence of capsules are, in combination, good field characters. The stem leaves are virtually unmistakable, but are only clearly seen when a capitulum is removed. S. girgensohnii (p. 284) is also usually green, and has fringed stem leaves, but only in the central portion of the leaf tip, with the leaf shoulders intact and rounded. The only Sphagnum with similarly shaped leaves is the rare S. lindbergii (p. 310), but in that species the stem leaves hang down the stem (not erect), and the whole plant is orange-brown. Habitat This species is shade-tolerant and is found in damp sites that are moderately enriched with nutrients, especially amongst birch (Betula), willow (Salix) and purple moor-grass (Molinia). Also found in more open sites, for example damp banks, sides of streams, ditches, lake margins, fens and Juncus mires. Photos John Birks & Des Callaghan (inset) Drawing Sharon Pilkington Text Andy Amphlett & Sandy Payne 283 Sphagnales Sphagnum palustre Blunt-leaved Bog-moss Section Sphagnum 1 cm Top of shoot 1 cm 5 mm Winter colours 1 cm Identification S. palustre is rather variable in colour, forming large, untidy mats or loose hummocks that are green to yellow-brown, with or without a contrasting capitulum centre. The most distinctive plants have capitula with the centre arched above the outer part, the centre salmon-pink to brick-red or dark brown (especially in the autumn and winter), contrasting with paler spreading branches. Spreading branches in the outer part of the capitulum and just below are usually elongated and narrowly tapering. Fascicles have 2–3 spreading and up to 4 pendent branches. The basal part of branch leaves is usually held at an angle of less than 45° to the branch stem, though the upper part can be widely spreading to almost recurved. Capsules are occasional. Similar species Well-marked forms are distinctive. Some compact, uniformly coloured forms with rather blunt-tipped spreading branches are virtually indistinguishable in the field from forms of S. papillosum (p. 278) and S. affine (p. 277), and require confirmation under a microscope. In wet or shaded habitats, S. palustre often has branch leaves with a tip that is strongly curved away from the branch, resembling S. squarrosum (p. 281), but that species does not have hooded branch leaves, and has a narrow stem cortex. Very dense forms, for example on sand and gravel by streams, can look superficially like S. compactum (p. 295). That species has minute stem leaves and a narrow stem cortex. Also see S. magellanicum (p. 280). S. palustre var. centrale (Smith, p. 52) can only be identified by microscopical examination of transverse sections of branch leaves. It is apparently rare or overlooked in Britain. Habitat The most shade-tolerant of the species in this Section, found in sites that are moderately enriched with nutrients, for example wet woodland, ditches, stream margins and flushes. Photos Sharon Pilkington (left), David Holyoak (top right) & Graham Motley (bottom right) 279 Drawing Sharon Pilkington Text Andy Amphlett & Sandy Payne Sphagnales Sphagnum squarrosum Spiky Bog-moss Section Squarrosa Branch leaf 4 mm Stem leaf 1 mm 1 mm 1 cm Whole 5 mm fascicle Identification Robust, bright green, spiky-looking plants. Branch leaves, wide in the basal half, are abruptly contracted to a pointed, tapering, tubular tip, which is distinctly curved away from the branch. The terminal bud is large and conical, immersed or slightly projecting above the rest of the capitulum. Stem leaves are large, rectangular, broad across the tip, and weak and floppy. Capsules are common. Similar species Typically robust forms are easily identified.S. palustre (p. 279) in very wet or shaded sites can have branch leaves that strongly curve away from the branch, and is of a similar size. However, that species has hooded branch leaves and a wide stem cortex. Small plants are very similar to green forms of the closely related S. teres (p. 282) in which the leaves curve only slightly away from the branch. The terminal bud offers a useful discriminating character: more or less immersed in S. squarrosum, standing well above the capitulum in S. teres (view capitulum from the side). However, some forms can be problematic to distinguish, even when using microscopic characters, and the best solution is to look in the vicinity for more characteristic specimens of one or both species. Also see S. strictum (p. 294). Habitat Typically found in swampy ground that is moderately to well-enriched with nutrients, such as in wet woodland, or amongst sedges (Carex), rushes (Juncus) or purple moor-grass (Molinia), for example on stream banks, in ditches, or in flushes on moorland. Occasionally found at high altitude in wet, rocky corries. Photos John Birks & Fred Rumsey (inset) Drawings Sharon Pilkington Text Andy Amphlett & Sandy Payne 281.