Festuca arundinacea Schreber ( F. elatior L. ssp. arundinacea (Schreber) Hackel)
2001; Wiley; Volume: 89; Issue: 2 Linguagem: Inglês
10.1046/j.1365-2745.2001.00561.x
ISSN1365-2745
AutoresDavid J. Gibson, Jonathan A. Newman,
Tópico(s)Turfgrass Adaptation and Management
ResumoA perennial grass producing large, loose, but sometimes dense, tussocks, normally without short rhizomes, and without stolons. Culms are unbranched, smooth (or rough below panicle) and erect, (39)45–120(200) cm in height. The lower sheaths are not fused, and are smooth and rounded on the back. Ligule, < 2 mm, membranous with ciliate auricles (cilia often few, and wearing off with age). Leaves, dark-green, stiff, usually flat, 10–60(105) cm long, (1)3–12 mm wide, distinctly ribbed above, rough or smooth below only, scabrous on margin, and tapering to a fine tip. Panicles (6)10–50 cm long, lax and wide, erect or pendant, lanceolate to ovate, green or purplish, with many rough branches, which are mostly in pairs; lowest two nodes with 2–3 subequal branches, each with 5–15 spikelets, the shorter branch with (3)4–many spikelets. Pedicels up to 8 mm long. Spikelets elliptic to oblong; (8)9–18 mm long, with 3–10 florets, disarticulating beneath each lemma at maturity. Glumes persistent, often purple-tinged, subequal to equal, pointed; lower narrowly lanceolate, 3–6 mm long, one-nerved; upper lanceolate to lanceolate-oblong, 4.5–7 mm long, three-nerved. Lemmas rounded on back, overlapping, or with margins incurved, lanceolate or oblong-lanceolate in side view, pointed to blunt, 6–7.5(10) mm long, firm except for the membranous upper margins, five-nerved, broadly rounded on back with fine, rough awn, when present, 0.5–3.5(6) mm extension of the middle nerve. Paleas as long as lemmas with rough keels. Three stamens with anthers 3–4 mm long. Caryopses (grains) tightly enclosed by the lemma and palea (Terrell 1979; Hubbard 1984; Fl. Eur. 5; Sell & Murrell 1996; Stace 1997). Mean caryopsis oven-dry weight 1.26 mg (Grime et al. 1981). Native. This is a complex species that, with the related Festuca pratensis, is referred to as F. elatior in much of the older literature (Terrell 1979; Reveal & Terrell 1991). Five subspecies are recognized in Flora Europaea (Fl. Eur. 5). Subspecies arundinacea occurs throughout the range of the species except for the southern half of the former USSR. Subspecies uechtritziana occurs in south-east France, but has been naturalized in central Europe, subspecies atlantigena occurs in south-west Europe, subspecies fenas in south and south-east Europe, and subspecies orientalis in south-east and eastern central Europe. Because of its importance as a pasture grass, there are numerous cultivars of F. arundinacea. The most widely grown cultivar in Britain is S170, a 24-clone synthetic cultivar developed at the Welsh Plant Breeding Station, Aberystwyth, from clones in Buckinghamshire, Pembrokeshire, France, South America and USA (Asay et al. 1979). S170 is endophyte-free (Latch et al. 1987), and highly productive, especially compared with other British forage grasses in the winter. Other cultivars may out-yield S170 at certain times of the year, e.g. an Algerian ecotype was found to have faster leaf growth rates than S170 during the winter (Chatterjee 1961; Robson 1967). Ueyama & Sato (1994) noted that the growth characteristics of native populations of F. arundinacea from Morocco and Portugal reflected their geographical origin. Different cultivars of F. arundinacea can markedly affect the botanical composition of mixed swards (Sugiyama & Nakashima 1991). The distribution of F. arundinacea in the British Isles is shown in Fig. 1. It is widely distributed and common throughout the British Isles, especially on rough and marginal ground over a wide variety of soil types (Stace 1997). It is recorded from the Isle of Man, the Isle of Wight, and the Channel Isles (Atl. Br. Fl.). On Anglesey, F. arundinacea occurs along riverbanks and by the sea (Roberts 1982). It is uncommon in the Scottish Highlands, but present in coastal areas. Murray & Birks (1980) note that F. arundinacea is rare and restricted to roadsides in Scotland. However, it is also noted as a species of low constancy in Agrostis tenuis (capillaris)–Festuca spp. communities on mesotrophic gleys from the Cheviot Hills of south-east Scotland (King 1962). It is rare along roadsides of the Outer Hebrides (Pankhurst & Mullin 1991). It is fairly frequent in Ireland along riversides, and in woods and damp fields (Webb 1959). Preston & Hill (1997) classify F. arundinacea as a member of the Eurosiberian Southern–temperate element of the British and Irish vascular flora that has been widely naturalized outside its native range. The distribution of Festuca arundinacea in the British Isles. Each dot represents at least one record in a 10-km square of the National Grid. (○) Pre-1950; (●) 1950 onwards. Mapped by Mrs J.M. Croft, using Dr A. Morton's dmap program, Biological Records Centre, Monks Wood, mainly from data collected by members of the Botanical Society of the British Isles. Festuca arundinacea is widely distributed as a native grass in temperate and cool climates throughout Europe (north to 62° in Scandinavia), North Africa, west and central Asia, and Siberia, but is absent from most of north, central and eastern Russia (Fig. 2). It occurs throughout these areas except in the Faeroes, Iceland, northern (former) USSR and Spitsbergen (Fl. Eur. 5). In north-west Europe, it is mainly limited to coastal areas around the Baltic, with some inland locations in southern Sweden (Atl. N.W. Eur.). Because of its value as a pasture grass, it has been introduced in North and South America, Australia, New Zealand, and south and east Africa. In these countries it is often naturalized, for example on New Zealand's South Island, F. arundinacea replaces the native grass Hierochloë redolens on the deep soils of coastal dunes and talus slopes (Johnson 1993). The distribution of Festuca arundinacea in Europe and Asia. (●) Isolated occurrences, (▪) ssp. arundinacea, (- - -) ssp. orientalis, (- – -) ssp. fenas (redrawn from Hultén & Fries 1986). In Britain, native stands of F. arundinacea occur principally between sea level and 50 ft (15.2 m) above (Alt. range Br. Pl.). However, there are several records of occurrence above 500 ft (152 m) (Atl. Br. Fl.) and in Cumbria the altitudinal limit is recorded as 430 m (Halliday 1997). In Europe, F. arundinacea occurs principally at sea level but it has been recorded from 2760 m in the High Atlas mountains of Morocco (Robson & Jewiss 1968a). The range of Festuca arundinacea in Europe (Fig. 2) corresponds in the north in Scandinavia to a January mean of −5 °C and altitudes < 200 m, and in the south to a mean July temperature of 25 °C (Thran & Broekhuizen 1965). Within this area, average yearly precipitation ranges from 2000 mm in the Alps to < 500 mm in central Spain. Wind damage in the field is not reported, but glasshouse experiments show epidermal damage leading to increased transpiration, water loss and reduced leaf growth at high wind-speed (37 mm s−1) (Grace & Russell 1982). Festuca arundinacea is most commonly found on level to gently sloping wet, lush meadows and pastures, as well as damp to well-drained grasslands. It occurs occasionally on quite steep slopes such as the upper cliff-scrub of coastal cliffs in Dorset. In Derbyshire F. arundinacea was recorded on a 40° SSE-facing slope (Clapham 1992). As a component of Brassica oleracea maritime cliff-ledge communities, F. arundinacea occurs on slopes up 80° (Rodwell 2000). It is often and sometimes plentiful along roadside verges, railway embankments and field margins. It is relatively plentiful in coastal areas, especially on clay sea-cliffs in southern Britain. When present in salt marshes it seems to be limited to an uppermost zone that is effectively freshwater and only rarely subjected to tidal flooding. The authors have recorded F. arundinacea on slopes of all aspects in Britain. On chalk grassland, F. arundinacea is limited to the cooler, richer, deeper and moister soils of temporarily ungrazed north-facing slopes (Tansley 1968). It is recorded by Perring (1960) as being in the most oceanic of five groups of chalk grassland species. The greatest cover of this group of species comprising 26 others is in Yorkshire and Dorset. Festuca arundinacea occurs on a wide variety of substrates; commonly these are poorly drained, alluvial soils. In Dorset, Kent and North Yorkshire, communities that include F. arundinacea are found on clay cliffs, and in Wiltshire on calcareous base-rich soils over chalk and oolite (Rodwell 1992). In the Sheffield area, F. arundinacea most frequently occurs in wasteland over calcareous strata, but is also widespread in wetland, skeletal, pasture and spoil habitats (Grime et al. 1988). Modal soil pH for the species in these communities was 7.0–7.9 with a range of 2 pH units. In Warwickshire, F. arundinacea is noted as being particularly abundant on calcareous soils and was recorded from roadsides and railway banks (37% of records), grassland (34%), watersides and marshes (17%), hedgerows and scrub (10%), and other habitats (Cadbury et al. 1971). In Sussex, most of the occurrences of F. arundinacea noted by Wolley-Dod (1937) were close to the coast on alluvium; however, additional sites were over Cretaceous sands, clay or chalk. Rendzina soils of the Ononis repens subcommunity of MC11 containing F. arundinacea were reported with a pH of 7.0 ± 0.5 and calcium content of 102 ± 23 µmol g−1 (Rodwell 2000). In farm swards from the Midlands, Yorkshire and Lancashire regions, F. arundinacea was most frequent on soils with a pH > 6.0. Leys of F. arundinacea accumulated 0.17–0.35% organic carbon in the top 15 cm of the soil after 4 years (Clements & Williams 1964). In continental Europe, F. arundinacea occurs on soils varying in nutrient availability from rich to moderately poor, but which are all generally moist or inundated for part of the year (Sýkora 1983). In the Netherlands, F. arundinacea-dominated vegetation common on dikes occurs on heavy clay soils (Sýkora 1982a). In Belgium, pioneer vegetation including F. arundinacea was colonizing gravel and sludge bordering the River Meuse (Le Brun et al. 1955). In Sweden, F. arundinacea is recorded from glacial till containing limestone fragments over pre-Cambrian granites, gneiss and other acid igneous rocks (Cramer 1993). In south-west Germany, the species was recorded on low-nutrient vertisols and cambisols with a high clay content over gypsum red marl rock (Fix & Poschlod 1993). The Ellenberg indicator values for F. arundinacea are 7, 7, 4 and 2 for moisture, pH, nitrogen, and salinity, respectively (Ellenberg et al. 1991). Near the Caspian Sea, F. arundinacea was recorded in solonchák meadows on soils high in soluble salts (mainly NaCl and Na2SO4) by Keller (1927). In wet grasslands in central Spain, F. arundinacea is an indicator of subalkalinophyte communities occurring on soils of pH 7.7–8.3 (Rey Benayas et al. 1998). Festuca arundinacea is a species of damp grasslands, riverbanks, salt marshes, sea-cliffs and sea shores (Fl. Eur. 5). In Britain, F. arundinacea occurs as a component of 19 plant communities (six mesotrophic grasslands, two calcareous grasslands, two mires, two swamps, five maritime communities and two communities of open habitats), as defined by the National Vegetation Classification (Rodwell 1992, 1995, 2000). Festuca arundinacea is most frequent as an occasional to constant species (Table 1) in the following communities: MG4. Alopecurus pratensis–Sanguisorba officinalis grassland occurs in seasonally-flooded land with alluvial soils traditionally managed as hay-meadows in the Midlands and southern England. These grasslands were subjected to light winter grazing and fertilized lightly with organic manure. An annual hay crop was taken in spring. MG4 is species-rich without a single dominant species. Festuca arundinacea has a constancy of II in MG4, which has no subcommunities. Constant species for MG4 and other communities in which F. arundinacea is important are given in Table 1. MG12. Festuca arundinacea grassland is characteristically ungrazed and unimproved, and occurs on moist, free-draining soils of frequently inundated estuaries and salt marshes on the south and west coasts of England and Wales. This community is also found on Arran in Scotland and clay cliffs in Dorset, Kent and North Yorkshire. Large tussocks of F. arundinacea characterize MG12, giving it a constancy of V. Festuca rubra and Agrostis stolonifera are also abundant and have a high constancy (Table 1). This NVC vegetation type is included with MG11 and MG13 in the Agrostis stolonifera–Festuca arundinacea sward CORINE biotope 37.242, a grassland of occasionally flooded river valley meadows (Commission of the European Communities 1991). Festuca arundinacea is also found with lower constancy (I) in three further mesotrophic grasslands: Cynosurus cristatus–Centaurea nigra grassland (MG5), Holcus lanatus–Deschampsia cespitosa grassland (MG9) and Festuca rubra–Agrostis stolonifera–Potentilla anserina grassland (MG11). In addition, F. arundinacea can occur, although not as a normal constituent, in Cynosurus cristatus–Caltha palustris grassland (MG8). Despite being a component of MG5, F. arundinacea is not recorded from the Park Grass Experiment in which this community best characterizes the unfertilized plots (Dodd et al. 1994). CG3. Bromopsis erecta (Bromus erectus) grassland is widespread throughout England, especially over the chalk of the North and South Downs, on the oolite of the Cotswolds and Northamptonshire, and the Magnesian limestone of West Yorkshire. Within these areas, CG3 occurs in lightly grazed or ungrazed areas on calcareous, base-rich soils. Dense tussocks of Bromopsis erecta dominate this grassland in which species richness is reduced compared with some other calcareous grasslands. Festuca arundinacea occurs in three of four subcommunities with an overall constancy of I, but reaches III in the Festuca rubra–Festuca arundinacea (CG3d) subcommunity. The relatively impoverished CG3d was the most extensive of the Bromopsis erecta grasslands surveyed in England and Wales, occurring on 7894 ha (Blackstock et al. 1999). Festuca arundinacea is also found at low constancy in two subcommunities of Festuca ovina–Helictotrichon pratense grassland (CG2). S21. Bolboschoenus maritimus swamp is dominated by a dense cover of 60–80 cm high B. maritimus. Other species are infrequent. S21 is characteristic of ill-drained brackish sites on coastal salt marshes on all coasts of the British Isles as far north as Sutherland. Festuca arundinacea has an overall constancy of I occurring in three of four subcommunities. It is most frequent in the Potentilla anserina subcommunity, where it attains a constancy of II. S26. Phragmites australis–Urtica dioica tall-herb fen is a very variable and frequently species-poor community, characteristic of eutrophic, circumneutral to basic water margins and mires that remain moist year round. Although S26 occurs naturally in some nutrient-rich, open-water transitions and flood-plain mires, its distribution is also related to disturbed or contaminated fen surfaces. Festuca arundinacea has an overall constancy of I and is most frequent in the Oenanthe crocata subcommunity where it attains a constancy of II. SM18. Juncus maritimus salt marsh is widespread along the west coast of Britain as far north as Argyll (Adam 1981). Festuca arundinacea has an overall constancy of II and is most abundant with a constancy of V in the F. arundinacea subcommunity. This subcommunity, equivalent to Adam's (1981)Festuca arundinacea–Juncus maritimus nodum, occurs at the highest levels on salt marshes, and is species-rich with considerable floristic heterogeneity between stands. Willis (1990) noted the presence of F. arundinacea in this community along the old shoreline at Berrow salt marsh, north Somerset. SM28. Elytrigia (Elymus) repens strandline occurs in upper salt marshes below the main drift line from Wales, northern England, south-west and north-east Scotland (Adam 1981), and is equivalent to Adam's (1981)Agropyretum repentis maritimum nodum. Festuca arundinacea can dominate the vegetation of this community and occurs with a constancy of II. MC4. Brassica oleracea maritime cliff-ledge community occurs on dry calcareous cliff-tops and splash zones on sheltered coasts in southern England. An unstable substrate maintains shallow, dry, often fragmentary rendziniform soils. Festuca arundinacea is present only in the Ononis repens subcommunity, which is transitional to Mesobromion calcareous grasslands. MC11. Festuca rubra–Daucus carota ssp. gummifer maritime grassland is a sea-cliff community confined to calcareous rocks with rendziniform soils most common on the chalk and limestone cliffs of the south coast west of Dorset. Festuca arundinacea occurs in all three subcommunities and is most abundant with a constancy of II in the Ononis repens subcommunity. Festuca arundinacea often occurs as an infrequent or only locally abundant member of other NVC communities, e.g. it has been recorded for 40 years as a component of roadside verge vegetation (MG1 Arrhenatherum elatius grassland) over Cotswold oolite at Bibury, Gloucestershire (Yemm & Willis 1962; Grime et al. 1994). It is a species of low constancy in two open vegetation communities: the OV26 Epilobium hirsutum and OV38 Gymnocarpium robertianum–Arrhenatherum elatius communities (Rodwell 2000). In continental Europe, F. arundinacea occurs as a diagnostic species of the Molinio-Arrhenatheretea R. Tx. 1937 class of temperate heathlands and grasslands (Mucina 1997). It is widespread in several associations associated with moist habitats. A selection of communities containing F. arundinacea is given in Tables 2 & 3 to illustrate its geographical and ecological range. In western Europe, including Ireland, F. arundinacea forms a component of the Lolio-Potentillion anserinae Alliance of inundated pastures (Sýkora 1982a,b,c). Festuca arundinacea is a character species in the Potentillo-Festucetum Arundinaceae Association (Class Plantaginetea majoris) in Ireland (White & Doyle 1980). In the Mediterranean region, F. arundinacea is an important and locally dominant species of arid azonal meadows (Le Houérou 1993). These moist meadows occur in enclosed moist depressions and provide forage for livestock in the summer. Festuca arundinacea is one of the most commonly seeded species on poorly drained clay soils in cleared areas of the semiarid to humid maquis of Tunisia, Morocco, Spain, Portugal and southern France, and on marginal croplands of semiarid and subhumid zones (Le Houérou 1993). Tansley (1968) records F. arundinacea as being 'well taken by stock'. Nevertheless, within the chalk grasslands it is common only on temporarily ungrazed, steep, north-facing slopes where soil moisture is abundant. Hearn (1995) has indicated that F. arundinacea is one of 18 herbaceous species that would likely dominate National Trust calcareous grasslands, sand dunes and sea-cliff habitats unless they were controlled by grazing. Despite its occasional inclusion in UK seed mixtures, Deakins (1979) notes that F. arundinacea is never favoured by grazing animals compared with other pasture grasses, probably because of its coarseness. Mazzanti et al. (1994) showed that continuous grazing by sheep of F. arundinacea plants from swards in France increased the number of tillers and reduced leaf extension rates. Deficient nitrogen application to these swards reduced herbage production principally through a reduction in tiller density. Compared with plants grazed by sheep, cattle-grazed F. arundinacea plants in New Zealand were 102% heavier, with greater numbers and lengths of stolons and flower heads (Hume & Brock 1997). In a field competition experiment, monoculture turves of F. arundinacea were rapidly invaded by tillers of Festuca rubra and Lolium perenne from neighbouring monocultures, especially when grazed by lambs (Silvertown et al. 1994). By contrast, F. arundinacea was readily able to invade monocultures of Poa pratensis in this experiment when turves were ungrazed in the winter and only lightly grazed in the summer. Festuca arundinacea is reported as being palatable to grazing horses (Archer 1973). In an investigation of community change in species-poor deciduous forest (formerly an overgrown grassland) in Estonia, F. arundinacea invaded plots from which the trees and shrubs were clear cut, the vegetation was mown, and the edges were root-trenched (Zobel et al. 1996). Festuca arundinacea similarly invades sheep-grazed scrub communities on embankments of the Zak van Zuid-Beveland in the Netherlands (Sýkora et al. 1990). In a competition pot experiment with Lolium perenne under ambient and elevated temperature and carbon dioxide, F. arundinacea cv. Barcel was the less aggressive competitor, especially under elevated carbon dioxide and temperature (Teughels et al. 1995). In competition experiments with Lotus corniculatus, a high-yield-per-tiller genotype of F. arundinacea was less competitive than a low-yield-per-tiller genotype (Zarrough et al. 1983). Festuca arundinacea often forms large, densely tillered clumps in moderately tall vegetation on wet or moist soils. When the clumps get very large with > 150 vegetative tillers, the outermost tillers become procumbent, growing along the soil surface but without rooting. When the species is abundant, such as on fairly rich soil, it is often patchily distributed, in an open-structured sward among the other perennial plants. In occasionally mown roadside verges, such as in the Bibury road verges, Gloucestershire (Grime et al. 1994), it can be abundant and locally dominant, occurring as small clumps that are difficult to distinguish from each other. Festuca arundinacea is a stress-tolerant ruderal (Grime et al. 1988). It is one of a group of species promoted by burning on embankments and dikes in the Netherlands (Beeftink 1975). Morphological features are highly correlated, and the largest plants have many vegetative and flowering tillers, long and wide leaves, and tall flowering culms with long panicles, long and wide upper culm leaves, and many spikelets. The largest plants in a comparison across habitats in southern England were from an ungrazed waste ground (MG9) dominated by Arrhenatherum elatius, Dactylis glomerata, Deschampsia cespitosa and Rubus fruticosus agg. A comparison of morphological characteristics of F. arundinacea from this and other habitats is provided in Table 4. As this species occurs in a wide variety of grasslands, including salt marsh and sea-cliff grasslands in the UK, and across a geographical range from northern Europe to North Africa, it is likely tolerant of a wide range of temperature and moisture conditions. Robson & Jewiss (1968a) found varieties of F. arundinacea from North Africa to survive and grow more rapidly under glasshouse conditions during the winter than the British S170 variety. Thomas & Stoddart (1995) noted that ecotypes of F. arundinacea from the coldest habitats produced smaller, greener leaves when chilled than ecotypes from warmer habitats. Leaf growth is principally related to temperature when nitrogen is not limiting (Gastal et al. 1992). Seedlings of F. arundinacea transferred from moderate (17/14 °C) to low temperature (7/4 °C) acclimated rapidly within two plastochrons to favour allocation of assimilates to growing tissues (Pearce et al. 1990). Ten-week-old seedlings of F. arundinacea subjected to temperatures of −16.5 °C or lower for 6 hours on 9 successive days subsequently died within 4 weeks (Robson & Jewiss 1968a). North temperate ecotypes were substantially more cold hardy than Mediterranean ecotypes at –15.0 °C with 74–94% and 6–14% of the seedlings alive after 4 weeks, respectively. Water stress in F. arundinacea leads to leaf rolling or folding, stomatal closure and a decline in transpiration rate (Renard & Francois 1985). Leaf rolling follows a loss of turgor in the leaf's bulliform tissues, causing the adaxial surface to roll inside. Generally, F. arundinacea recovers rapidly from drought, and survival and recovery are enhanced in endophyte-infected plants (Bacon 1993; Elmi & West 1995). Wilman et al. (1998) found F. arundinacea to be the most drought-tolerant grass when compared with seven others within the Lolium–Festuca complex. Drought hardiness varies among cultivars (White et al. 1993) and is reduced when F. arundinacea is exposed to wind (Grace & Russell 1977). In the Netherlands, F. arundinacea was recorded as one of a suite of species that occurred in sites of brackish pastures inundated for up to 4 weeks in both summer and winter (Sýkora 1983). On the Aran Islands, F. arundinacea is recorded as occurring near the upper limit of flooding around the turloughs on Inishmore (Webb 1980). Continuous flooding imposed on 7-week-old seedlings did not cause serious damage for 8 months (Razmjoo et al. 1993). The dense fibrous rootstock of F. arundinacea forms an extensive root system that has the ability to draw water from > 1 m in the soil profile (Garwood & Sinclair 1979). Frequent cutting of shoots reduces the root system and hence the plant's drought tolerance. In a comparison with seven other grasses in the Lolium–Festuca complex, F. arundinacea had the greatest number and weight of roots at 50–100 cm soil depth. Isolated F. arundinacea grows into a large, dense tussock. Glasshouse-grown seedlings of S170, sown in April 1962, showed almost exponential growth in June and July, and developed, on average, 55 tillers per plant by 17 July with 10.3 leaves on the main stem (Robson 1968b). Tiller production declined thereafter, but increased again in September to just over 300 tillers per plant by December. No new tillers died before mid-July. Tussocks develop from seedlings through the development of two coleoptile tillers and the primary tillers in acropetal succession in the axils of leaves (Robson 1968b). The first tiller develops in the axil of the first leaf on the stem. Secondary tillers subsequently arise in the axil of leaves on the primary tillers. Stomata occur in rows beneath the veins at a density of 33 mm−2 on the lower (abaxial) leaf surface and 61 mm−2 on the upper (adaxial) leaf surface (Fitter & Peat 1994). Festuca arundinacea is listed as having vesicular–arbuscular mycorrhizas (Harley & Harley 1987). However, in a pot experiment, in which F. arundinacea was included in a suite of cool-season grasses, mycorrhizal fungi did not affect root number or diameter (Hetrick et al. 1991). Festuca arundinacea is a hemicryptophyte, with over-wintering leaves produced in late summer and autumn. Vegetative growth is fast in isolated tussocks, owing to the rapid production of new tillers. Festuca arundinacea is considered to have a type I or II transient seed bank with most of the seed germinating shortly after being shed (Grime et al. 1988; Thompson et al. 1997). It was absent from the seed bank of fertilized hay meadows (MG5 and MG8 categories) in Somerset, despite its presence in the above-ground vegetation (Kirkham & Kent 1997). Similarly, F. arundinacea was absent from the seed bank of Baltic seashore meadows in south-west Finland, despite being common in the established vegetation (Jutila 1997, 1998). Festuca arundinacea is an allohexaploid (2n = 6x = 42 chromosomes) (Berg et al. 1979); however, individuals with 2n = 28 and 70 are also reported (Fl. Eur. 5). The progenitor species are believed to be F. pratensis Huds. (2n = 2x = 14) and F. glaucescens Hegetschw. & Heer. (2n = 4x = 28) (Sleper & Buckner 1995). The identification of these progenitors has been confirmed using DNA restriction fragment length polymorphism (Xu et al. 1992). cpDNA restriction-site data suggest that F. glaucescens, or a close ancestor, was the female parent of F. arundinacea in a cross with F. pratensis (Charmet et al. 1997). These analyses also indicated a high level of genetic relatedness between F. arundinacea and Lolium perenne. 2C DNA content varies from 13.5 pg to 52.8 pg, depending upon the variety (Fitter & Peat 1994; Bennett et al. 1997). Festuca arundinacea was the least productive, equal to Dactylis glomerata, of the nine main agricultural grasses in the UK with a yield from the first cut at 63 days of 4400 kg ha−1 (Deakins 1979). Partially irrigated and fertilized (400 kg N, 50 kg P and 250 kg K per hectare per year) swards of F. arundinacea cut at 6-week intervals yielded 20 325 kg ha−1 in a 1974 study conducted in Hurley, Berkshire (Garwood et al. 1979). High levels of manuring yielded 11 128 kg ha−1 in trials of S170 F. arundinacea in Auchincruive, West Scotland (Hunt 1961). By comparison, the 'Early' and 'Rhenish' varieties yielded 10 836 kg ha−1 and 10 287 kg ha−1, respectively, in these trials, and 'S215' meadow fescue (Festuca pratensis) yielded 9649 kg ha−1. Frame (1973) noted a convex curvilinear relationship between annual yield and nitrogen treatments of S170. There was a significant interaction of nitrogen-rate and harvesting frequency, with yields increasing under reduced harvesting frequency, but the magnitude of the differences varied among nitrogen-rates. Crude protein contents showed linear relationships with nitrogen-rate and harvesting frequency. Field trials in the Cheviot Hills of south-east Scotland showed that yield of F. arundinacea was highest in well-drained, compared with waterlogged, sites. Linear regressions of yield were positively related to percentage soil oxygen, percentage soil carbon dioxide, and soil moisture tension (Rogers & Davies 1973). Field trials in the north-west region of the former USSR showed that maximum production (14 461 kg ha−1) and total energy yield (256 600 MJ ha−1) of F. arundinacea var. Zapadnaya was achieved with two cuttings per season and 360 kg N ha−1 (Spasov & Kornyshev 1989). Production and energy yield were lower with more frequent cutting and lower applications of fertilizer. Because of its use as a pasture and tu
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