Radiola linoides

Radiola linoides
Radiola linoides
Scientific classification
Missing taxonomy template (fix):	Radiola (plant)
Synonyms
Linodes radiola Kuntze Linum exiguum Salisb. Linum millegranum (Sm.) Gray Linum multiflorum Lam. Linum radiola L. Linum tetrapetalum Gilib. Millegrana radiola (L.) Druce Radiola dichotoma Moench Radiola filiformis Dulac Radiola linoidea St.-Lag. Radiola millegrana Sm. Radiola multiflora Asch. Radiola tetrapetala Steud.

Radiola is a monotypic genus of flowering plants belonging to the family Linaceae. It just contains one species, Radiola linoides Roth It has the common names of 'allseed' and 'flaxseed'. It has a very short stem which is repeatedly subdivided, with a pair of very small leaves and a single white flower at each fork and at the end of the branches. It has leaves which are opposite arranged, oval (in shape) and sessile.

Description

Herbs, 3–10 cm; dichotomously branched. Leaves spreading; blade 2–6 mm, base clasping. Inflorescences: bracts usually leaflike, entire. Pedicels ascending. Flowers: sepals equal, oblong, apex deeply 3-fid; petals widely spreading, ovate, 1–1.5 mm, slightly narrowed at base; stamens 0.5–0.8 mm; anthers white. 2n = 18. Phenology: Flowering Jul–Aug. Habitat: Vernally damp sandy, acidic, open ground, roadsides, logging trails, rocky outcrops. Elevation: 0–100 m.

small, delicate looking, has very small oval opposite leaves, 1.3 - 7.5cm tall, flowers july - august, 1mm across, tiny white petals same length as sepals, 4 stamens, flowering stem repeatedly branched, flowers at branch tips, globular fruit, allseed has multiple seed production hence common name, found on the damp patches of heaths in southern england, but found elsewhere as well.

Status Native Trends R. linoides suffered a considerable decline before 1930, largely due to the loss of lowland heaths or a lack of grazing and disturbance on them. These losses have continued in England: it was lost from 95% of a sample of sites in Dorset between 1935 and 1992 and remaining populations are very small. Its distribution seems to be stable elsewhere. It is easily overlooked and may be under-recorded in some areas.

Radiola linoides Roth Allseed Radiola linoides is a diminutive annual, often only a few centimeters tall, with thin forked stems, opposite leaves and tiny white flowers with four petals as long as the four sepals. It is a calcifuge species of sparsely vegetated, well drained soils, found in short acid grassland, grazed flushes, rutted tracks, dune slacks, and woodland rides. Following substantial losses inland, it now has a mainly coastal distribution across western Ireland, south-west England and Wales, northwards along the coast to western and north-east Scotland, with outliers in southern England and East Anglia. It is assessed as Near Threatened in Great Britain as a whole, Vulnerable in England, but of Least Concern in Wales. Radiola linoides is a very small annual with prostrate to ascending, greyish-green, often purple-flushed forked stems, 1-6 (10) cm tall and 0.5mm in diameter. Plants have opposite, obovate-elliptic leaves (1.5-2 mm) that are 1-nerved and have transparent (hyaline) margins that appear ragged due to the presence of minute teeth or lobes (Poland & Clement 2009; Stace 2010). The tiny flowers (1 mm across) have four white petals ±as long as the four sepals. The capsules are c.1 mm wide, globose, and have 8 valves with 2-seeded compartments (locules). Plants produce very small (0.4-0.5 × 0.2-0.3 mm) obovoid to ellipsoid brown seeds that are slightly flattened on one side and have a smooth, lustrous surface (Bojňanský & Fargašová 2007). Seeds are able to persist in the soil after conditions have become unsuitable for mature plants to establish in the above-ground vegetation (Plassmann et al. 2009). R. linoides is therefore capable of opportunistically colonising areas from the seed bank when suitable conditions (e.g. bare, damp, open ground) become available, although it is not known how long the seed bank remains viable if unsuitable conditions continue for a prolonged period of time (i.e. more than five years). R. linoides is a plant of sparsely vegetated, damp, infertile, moderately acid peaty, gravelly or sandy soils, often found in drawdown zones or where there has been some poaching by livestock (Edwards & Pearman 2004). It is found in short acid grassland, heathland, grassy cliff slopes, grazed flushes, the rutted edges of tracks, woodland rides and firebreaks, at the edges of ponds, in sandy grassland, machair and dune slacks and in soil-filled rock crevices (Wilmore 2002; Chater 2010; Rand & Mundell 2011). Rodwell (2000) includes R. linoides as an associate of short open turf belonging to the NVC MC5 Armeria maritima-Cerastium diffusum subsp. diffusum maritime therophyte community but its NVC affinities are likely to be much broader and include a range of grassland and heathland types. Across Europe, R. linoides is also associated with annual-rich west Mediterranean siliceous grassland, the fumaroles of Pantelleria in Sicily, Juncus bufonius-dominated communities with Centunculus minimus and Centaurium pulchellum, and temporarily inundated small herb communities with associates including Elatine spp., Damasonium bourgaei and Samolus valerandi (Anon 2013). In the Netherlands, R. linoides is recorded from fields that are filled with water in the winter months for ice skating. Very small, smooth seeds are known to be able to survive internal (endozoochorous) dispersal by animals, and the combination of seed morphology and habitat suggests that R. linoides seed also has the potential to be transported long distances on the feet or feathers of wildfowl (Salisbury 1970) or on the feet or hair of cattle. R. linoides has been recorded as a host for Melampsora lini, a fungal pathogen responsible for rust disease on flax and linseed (Lawrence et al. 2007)

A small hairless, branched plant (easily overlooked) with clusters of tiny, short-stalked white flowers with four petals. The globose seed capsules are more noticeable than the flowers. Reddish, threadlike stems with opposite, one-veined leaves Flowering time: July-August. Annual Often found with Chaffweed (Anagallis minima)

Taxonomy

Radiola linoides allseed Other common names flaxseed Native to the UK - No

Family: Linaceae Radiola linoides * Allseed

The name 'allseed' is due to the multiple seed capsules on the plant, each containing 8 seeds.

It was originally named Linum radiola by Linnaeus in his book Sp. Pl. on page 281 in 1753. It was then later restored to a genus by Dillenius and re-named as Radiola linoides.

In 1753, L R was transferred to the genus Radiola, it assumed the name Radiola radiola, being a tautonym, it was not valid. In 1788, Roth gave the name as R L.

The genus has one known synonym of Millegrana Adans.

The Latin specific epithet of linoides means

. The genus was first described and published in Brit. Herb. on page 227 in 1756, and then the species was first published in Tent. Fl. Germ. Vol.1 on page 71 in 1788.

Distribution and habitat

Range

Its wide native range stretches from Europe (found within the countries of Albania, the Balearic Islands, the Baltic States (Estonia, Latvia and Lithuania), Belarus, Belgium, Bulgaria, Corsica, Czechoslovakia, Denmark, France, Germany, Great Britain (including Northern Ireland,), Greece, Hungary, Ireland, Italy, Netherlands, Norway, Poland, Portugal, Romania, Sardinia, Sicily, Spain, Sweden, Ukraine and Yugoslavia), parts of Russia (including; Central European Russia, Northwest European Russia and South European Russia), Macaronesia (including; the Canary Islands, Cape Verde and Madeira), parts of Africa (including; Algeria, Cameroon, Ethiopia, Madagascar, Malawi, Morocco, Tanzania and Tunisia), and also parts of western Asia (including; Lebanon,Syria and Turkey).

Africa MACARONESIA: Spain [Canarias], Portugal [Madeira Islands] NORTHERN AFRICA: Algeria, Morocco, Tunisia NORTHEAST TROPICAL AFRICA: Ethiopia EAST TROPICAL AFRICA: Tanzania WEST-CENTRAL TROPICAL AFRICA: Cameroon SOUTH TROPICAL AFRICA: Malawi Asia-Temperate WESTERN ASIA: Lebanon Europe NORTHERN EUROPE: Denmark, United Kingdom, Ireland, Norway, Sweden MIDDLE EUROPE: Czechoslovakia, Belgium, Germany, Hungary, Netherlands, Poland EASTERN EUROPE: Russian Federation-European part [European part (w.)], Latvia, Ukraine SOUTHEASTERN EUROPE: Former Yugoslavia, Albania, Bulgaria, Greece (incl. Crete), Italy (incl. Sardinia, Sicily), Romania, Turkey [İstanbul] SOUTHWESTERN EUROPE: Spain (incl. Baleares), France (incl. Corsica), Portugal (grin)

Extinct in: Switzerland

Introduced into: Maine, New Brunswick, Nova Scotia

freshwater dune slacks.

In Britain, it is found in acidic grasslands, heathlands and in Ireland growing with Plantago maritima in dense, exposed conditions.

Tingitan Peninsula, northwest Africa,

Habitat

Ecology A small annual of damp, bare, infertile, peaty or sandy ground in acid grasslands and heaths, by ponds, on tracks and in woodland rides. Near the coast it occurs in dune-slacks, sandy grassland, on machair, and in soil-filled rock cracks. Lowland.

Habitat: Damp, infertile ground on sand, peat or gravel; heaths, tracks, dune-slacks and paths.

A very small annual with forked thread-like stems, tiny opposite leaves and clusters of minute flowers, which have the petals no longer than the sepals. In bare moist ground, now much rarer than it used to be.