18 Plant Protection Quarterly VoI.12(1) 1997 and Ctenopsis have been considered to be The Biology of Australian Weeds. genetically distinct (Cotton and Stace 1977, Bulinska-Radomska and Lester 1986). The 30. Vulpia bromoides «L.) S.F. Gray) and V. myuros genus is now recognised as having four sections: Vulpia, Spirachne, Monachne «L.) c.c. Gmelin) and Loretia (Cotton and Stace 1977). Monachne was reinstated by Cotton and Al exandra Wallace, Great Southem Agricultural Research institute, Stace (1977) and follows an earlier group­ Agriculture Western Australia, Clive Street, Katanning, WestemAustralia 6317, ing of the genus by Dumortier (1824). Australia. V. bromoides and V. myuros are members of section Vulpia which is thought to be of more recent origin compared to the other Name Initially V. bramoides and V. myll ros were sections, having advanced noral features, Vulpia bromoidtS (L) S.F. Gray, Nat. Arr. included within the genus Fes/uCJl . How­ an annual habit, and a tendency to Brit. PI. 2:124 (1821) ever, as Fes/llea spp. are predominantly autogamy and polyploidy (Bulinska­ Vulpia myuros (L.) c.c. Gmelin, FI. Bad. 1:8 perennial and Vulpia spp. are almost en­ Radomska and Lester 1988). (1805) ti rely annual, they were an imperfect fit. A total of five species of Vlllpia have The common names are squirrel-tail and V. bromoides and V. myuros are so closely been recorded in Australia (Hnatiuk 1990). rat's-tail fescue respectively, but the two allied that when both were described by V. bramoides and V. myuros will be dealt species are also known collectively as Linnaeus, several botanists thought that with in detail in this paper. A distinct form 'silvergrass', 'hairgrass' and 'silkygrass'. he had described the same species twice. of V. myllm5, sometimes referred to as V. The genus Vulpia (named after the Ger­ This confusion was probably intensified megailira (Nutt) Rydb., has lemmas that man chemist 1.S. Vulpius) belongs to the by the ability of both species to alter their are ciliate towards the apex, and occu rs tribe Festuceae of the family Poaceae. growth form under adverse conditions throughout the range of V. myuros Oacobs (Henrard 1937). and McClay 1993). The genus Vulpia contains approxi­ • mately 20 species. For many years the ge­ Description nus was divided into five groups: Vulpia, Both of the species described below are Loretia, Spirachne, Ctenopsis and annuals. The following taxonomicdescrip­ Vulpiella. In more recent times Vulpiella tion is taken largely from Lamp el 01. (1990), Wheeler el III. (1982) and Stace (1980). Slender, erect, tufted annuals from 5--60 b cm high (Fig ure la). Culms erect, slender, , Figure 1. (a) Vulpia mljuros, typical growth habit (from an original by C.A. Gardner, reproduced with the pennission of the WA Herbarium). Enlarged views of panicle and spikelet (b) V. bromoides, (c) V. myuros (originally published in Haflinger and Scholz (1981), reproduced here with the pennission of Ciba Australia). Plant Protection Qua rterly Vo I.l2(1 ) 1997 19 • pedicels 1-4 mm long and thickened. In­ fl orescence length may be reduced to a • spike or a single spikelet under adverse conditions (C unningham el al. 1992). Spikelets are awnless, 7-16 mm long. ob­ long to wedge shaped, disarticulating above the glumes and between the lem­ mas, 5-10 florets. The glumes are unequal and finely pointed and are the main deter­ minant between the two species. Vllfpia bromoides. The lower glume is 2.5-5 mm long. one half to Ihree quarters the length of the upper (Figure Ib); upper glume 4.5-9 mm. Lemma 45-7 mm long. rounded at the back, five-nerved, florets partial ly overlapping each other. Awn ter­ minal. slender and roughened, up to 13 mm long. Paleas sub-equal 10 lemmas, two roughened keels. Anthers one (to three), 0.3-0.6 mm long and included at anthesis. Ovary glabrous . Vllfpia rnyilros. The lower glume 0.4-25 .~ mm long, one tenth to two fifths as long as the upper (Figure Ic); upper glume2.5--65 b mm (including awn of up to I mm). Lemma 4.5-75 mm with an awn usually one to two times as long. 0.&-1.3 mm wide, • fin ely five-veined. Paleas sub-equal to lemmas, two roughened keels. Anthers 1 (to three), 0.4-0.8 mm and included at anthesis. Ovary glabrous. The basic chromosome number of the genus Vllfpia is seven. V. bramaides is dip­ loid (211=14) and V. myuros is hexaploid (211::42) (Cotton and Stace 1977). History Vllfpia bramaides and V. myllr05 were intro­ duced to Australia soon after settlement. The exact method of entry is unknown but it is likely that introduction occurred via ships' ballast and in contaminated forage, wool or attached to li vestock (KlootI986). Seeds of V. myllfOs were found in im­ ported grass seed (particularly perennial ryegrasses) as latc as 1952 (Broad 1952). V. bromoides was listed as an ornamental grass in a seed catalogue published in 1886, .~ so it is possible that it was introduced in this way to some areas and is in fact a gar­ den escape! (Pascoe 1886). Figure 2. The predicted distribution with locations that match the ideal Vu/pill bromoides and V. myllTOS were climate by 80% or greater (grey) and locations that match the ideal climate by first recorded in Australia soon after set­ 5~ 790/0 (diagonal line), plus the locations of existing herbarium records (solid tl ement and usually in areas of initial set­ tl ement; Tasmania 1837, Victoria (yarra) circles) for (a) V. bromoides and (b) V. myIIYOS. The mapped prediction is 1852 and South Australia (Hahndorf) 1848. based on a 1 Ie to grid. Later collections were well inland of the tufted or solitary, often branched (V. hairs, usually rounded, sometimes com­ original settlements; Western Australia bromoides). Leaf blades rolled in the bud, pressed or slightly keeled, sometimes pur­ (Kellerberrin) 1891 , Victoria (Swan Hill) green and finely pOinted, 1- 14 em long. ple tinged nea r base_ Inflorescence a nar­ 1889, interior of New South Wales 1880. 0.5-3 mm wide, upper surface with five to row one-sided panicle ca rried well clear of This indicates that lheyentered Australia in seven pubescent veins, rough near the tip the flag leaf (V. bramoides) or partly in­ the early years of European settlement and and on margins. lower surface slightl y cluded in upper-most leaf-sheath (V. spread quickly to suitable environments, glossy, glabrous or with a few hairs, indis­ mYllms), erect or slightly nodding, lanceo­ probably with stock and human move­ tinct mid-veins. Ligule membranous to 1 late, rather loose to compacted, 1-10 cm ments as agricultural expansion took place. mm long. white. Auricles absent. Leaf (Y. bro/twides) or 5-35 cm (V. my"ros) long. Vllipia bramoides and V. myur05 are sheath split, glabrous or with scatte red Inflorescence is green- purple in colour, now widely distributed (Gardner 1952, 20 Plant Protection Quarterly VoI.12(1) 1997 Lazarides 1981 , Lamp el al. 1990). Their sensitive to drought (Rossiter 1966) as able to achieve maximum yields at solu­ long presence in Australia coupled with they are shallow rooted (Ozanne and tion concentrations as low as 1 ~M (Asher their wide range through the southern Asher 1965). In consequence of this they and Loneragan 1967). At high phosphate half of the conlinent suggest that they are mostly found in the higher rainfall ar­ concentrations V. myu ros was unable to have reached the limits of their distribu­ eas of southern Australia (Velthius and absorb phosphate al increaSing rates ti on. Amor 1983). Their range encompasses the (Loneragan and Asher 1967). major cereal and livestock regions of Response of V. myllr05 to nitrogen appli­ Disbibution southern Australia. cation appears to depend on plant density. Both V. bromoides and V. myuros are na­ Vulpia bromoides and V. myuros have Cocks (1974) determined that, at low den­ tives of the western Mediterranean, south­ been found from sea level up to 610 m in sities, both Lolium rigidum Gaudin and Hor­ western and central Europe (Cotton and the British Isles (Hubbard 1968) and at deum leporillum Link had a greater dry 5tace 1976, Stace 1980). In the northern greater than 1000 m elevation on the weight increase than V. myl/ros following hemisphere, V. broN/aides is distributed northern tablelands of New South Wales nitrogen applications. At a higher plant further north than V. myul'OS, occurring as (Mdntyre and Whalley 1990) density, V. myul'OS responded as well as far north as Scotland and Sweden. In L. rigidum and beller than H. /eporinllm . L. north-western Europe V. bromoides is the Substratum rigidum and V. myuros both had greater more common of the two species, except In Western Australia, V. myuros is found absolute response than H. leporimlm when where V. myll ros has spread along railway mainly on light to medium textured soils response to nitrogen was compared at lines (Cotton and Stace 1976). V. bromaides which tend towards acidity (Rossiter similar amounts of available herbage is occasionally found in Russia and West­ 1966). A survey of the pastures of south­ (Cocks 1974). ern Asia, and is naturalized in North and eastern South Australia found that soils From the studies described above it be­ South America and Australasia. characterized by low to moderate potas­ comes clear that V. myurDS (and in all prob­ Vu/pia myuros is widespread throughout sium and phosphate status had the highest ability V. bromoides) tolerates soils with low southern and central Europe, reaching as incidence of V.