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BSBI NEWS 148 | September 2021 47
In December 2020, a single plant of a mystery grass
species was found growing on part of the medieval
town wall of Great Yarmouth (v.c. 27), close to the
historic quayside, by Bob Leaney and Jo Parmenter.
After all attempts to identify it failed, the specimen
was sent to the referee for alien grasses, Oli Pescott.
The general morphology and appearance
initially suggested an Eragrostis, although our plant
lacked the fringe of hairs which very often forms
the ligule in many members of this genus, and there
were some other unusual features: OP observed
that our specimen had long anthers at c. 1.4 mm,
thus ruling out the most commonly found annual
Eragrostis species listed in Cope & Gray (2009); this
feature also appeared to be somewhat atypical for
the whole genus, at least for those c. 90 members
that have been found in western Europe (Portal
& Duhem, 2002). Initially too, our specimen was
thought to have only two anthers, again, a less
common state in European Eragrostis, and indeed
in grasses generally (Clayton, 1990).
The issue with there being only two anthers was
eventually resolved by dissecting a number of other
orets, which showed that at least some had three
(so, some orets had undeveloped anthers, which
is apparently not uncommon in Poa; Soreng et al.,
2020).
OP then started to key the plant out ‘from
scratch’, using the tribe and genus keys in the rst
edition of Genera Graminum (Clayton & Renvoize,
1986): here it keyed to Eremopoa. Once the genus
was determined, it was a relatively simple matter
to assign the specimen to Eremopoa persica using the
recently published key of Gillespie et al. (2018).
These authors sink Eremopoa and a number of
other taxa into Poa subgenus Pseudopoa. Under this
treatment the Yarmouth plant would be named Poa
persica subsp. persica.
Unfortunately the process of identification
mutilated the specimen to a degree where a
photograph would not be particularly informative;
however, Figure 1 shows a pressed specimen held
by the British Museum.
Eremopoa persica (Trin.) Roshev. (Persian Meadow-
grass) re-found in Britain after a 60-year absence
BOB LEANEY, JO PARMENTER & OLI PESCOTT
Figure 1. Specimen of Eremopoa persica from
Galashiels, Selkirk (v.c. 79), held at the British
Museum.
ADVENTIVES AND ALIENS: Eremopoa persica re-found in Britain after a 60-year absence
48 BSBI NEWS 148 | September 2021
Identication characters
Eremopoa is distinguished from Poa on the basis of the
panicle branches being whorled (usually unwhorled
in Poa, at least when considered on a global basis),
and the lemmas being lanceolate to narrowly oblong
in side view (as opposed to ovate in Poa; Clayton
& Renvoize, 1986). It is this last feature which at
least partly accounts for the supercial similarity to
Eragrostis. Clayton & Renvoize also consider that,
whilst Eremopoa has a ‘recognisable facies’, it is also
‘barely distinct’ from Poa.
Ibrahim et al. (2016) describe the plant as a tufted
annual, with culms 5–50 cm tall, erect, geniculate,
and with glabrous sheaths. The leaves are basal
and cauline, and the sheaths longer than adjacent
internodes, glabrous, ribbed, margins smooth.
Ligules are 1–3 mm long, membranous, with a
lacerate apex. Leaf blades are 2–8 cm long, 1–2 mm
wide linear, at, accid, ascending, ribbed, scabrous,
margins smooth, apex acute. Panicles are 6–17 cm
long, (1.5–)3–5 cm wide, open, ovate. Spikelets
are 4–8.5 mm long, elliptic, laterally compressed;
lemmas 3–3.5 mm long, mucronate, awnless; anthers
1.4–2.6 mm long. See Figure 2 for illustration.
Eremopoa persica has often been subdivided into two
taxa, variously assigned at dierent ranks depending
on the treatment. For example, Gillespie et al. (2018)
distinguish these (within Poa persica in their case)
at the subspecies level, giving subsp. persica, with
pubescent lemmas and a relatively narrower panicle
length to plant height ratio, and subsp. multiora, with
glabrous lemmas and a relatively greater panicle
length to plant height ratio, and often more owers
per spikelet. The Great Yarmouth specimen keyed to
subsp. persica. Other authors prefer not to recognise
this distinction based on intergradation of characters
in their areas (e.g. Rahmanian et al., 2014; Missouri
Botanical Garden, 2021).
Eremopoa persica distribution
Eremopoa is a small genus of annual grasses distributed
from Egypt to western China (Gillespie et al., 2018),
and E. persica is native within this range across
southwestern Asia, occurring eastwards to Pakistan
and westwards into Turkey and Lebanon. In its
Figure 2. Eremopoa persica (Poa persica). (A) habit;
(B) ligule, sheath and blade; (C) inorescence; (D)
spikelet. From an illustration in Ibrahim et al. (2016)
Grasses of Egypt. Reproduced by kind permission of
the Smithsonian Institution Scholarly Press
native range it generally occurs in montane habitats:
for example, the altitudinal range in Pakistan is
given as between 1400 and 1900 metres (Missouri
Botanical Garden, 2021); lower altitudes are noted
for Iran (Rahmanian et al., 2014). Its natural habitat
is sandy and stony soils (Ibrahim et al., 2016). It has
spread into the eastern Mediterranean, including
northern Egypt (Gillespie et al., 2018) and has
also been recorded from Belgium (as a grain alien;
Verloove, 2006), France (introduced in wool) and
Norway (Greuter et al., 1984–2011).
Habitat and status in the UK
Eremopoa persica is described as ‘a casual of wool,
docks and wasteland’ by Ryves et al. in Alien Grasses
of the British Isles (1996); however it does not feature in
ADVENTIVES AND ALIENS: Eremopoa persica re-found in Britain after a 60-year absence
BSBI NEWS 148 | September 2021 49
the 4th edition of Stace (2019) and does not appear
in the BSBI’s Distribution Database.
Ryves et al. noted that herbarium specimens are
held by the British Museum (BM), Bristol Museum
(BRISTM), Oxford University (OXF), South
London Botanical Institute (SLBI), University of
Reading (RNG) and Kew (K). The NBN Atlas shows
that specimens are also held by the Royal Botanic
Garden Edinburgh Herbarium (E) and records from
the Bristol area by Bristol Regional Environmental
Records Centre (BRERC). The latter proved to be
derived from the specimens held by BRISTM.
The previous records, including those from
herbaria, are from the Scottish Borders, Leith Docks
and close to the River Avon near Bristol (see Table 1).
The rst record was from 1906 and the most recent
dates from 1961, a specimen from Galashiels, near
Selkirk (Figure 1).
The Yarmouth specimen was rooted in moss and
loose lime mortar on a sheltered west-facing ledge
built into the medieval town wall, and so is likely
to have experienced warm and very dry conditions
for much of the year. The other specimens have
variously been found on tips and docks.
Discussion
This is the rst record of the species for Norfolk;
however, as it is a rather unassuming little grass, it is
possible that it may have previously been overlooked.
Ryves et al. note an association with wasteland and
docks. Could it have persisted in the area around
Yarmouth quayside for all these years, or is it a
new arrival?
Eremopoa persica, as with many of the species listed
in Ryves et al., has always been considered to be
Table 1. Past records of Eremopoa persica in Great Britain
Date Collector Location/habitat Vice-
county
Type Held by
28 June 1906 J. Fraser Leith docks (wasteground) 83 Herbarium E
30 May 1937
Cecil I. Sandwith, J.P.M. Brenan
Ashton Gate, Bristol (tip) 34 Herbarium* BRISTM
27 May 1939
C.I. Sandwith
Avonmouth docks 34 Herbarium* BRISTM
18 June 1961 Galashiels, Selkirk 79 Herbarium BM
* record also on BRERC
a wool alien in the British Isles, and this mode of
introduction is the likely one for the four previous
records of the species. Wool aliens used to arrive in
imported eeces from New Zealand and Australia,
other locations in the southern hemisphere and from
Central Asia. This last region is the one in which
E. persica is known to occur (Gillespie et al., 2018).
Stace & Crawley (2015) identify the pathways by
which wool aliens can escape into the wild:
• At the port of entry during handling: this is the
likely source of the record from Leith docks and
perhaps also Avonmouth.
• In wool washing euent from riverside woollen
mills: the Galashiels record appears to t this
dispersal mechanism.
• From wool shoddy, which is then used as a soil
improver, either during the rail transport or
when material is spread: this mechanism may
explain the second Bristol record.
It is tempting to assume that the Great Yarmouth
record could be a recent or indeed historic
introduction with wool, but this is considered unlikely.
There is no evidence to suggest the importation of
wool via the port of Great Yarmouth in recent times
and modern wool transport is typically containerised.
The vast majority of the ‘wool aliens’ from the early
20th century have not been recorded for over half a
century and it is probable that their historic presence,
particularly in the case of the annual species, relied
on regular introduction. It is noteworthy that many
of those alien grass species which have persisted
in the British Isles and Ireland, and which have
a similar native distribution to Eremopoa persica
(for example Eragrostis cilianensis, Setaria viridis and
Digitaria sanguinalis), are associated with three modes
ADVENTIVES AND ALIENS: Eremopoa persica re-found in Britain after a 60-year absence
50 BSBI NEWS 148 | September 2021
of introduction: birdseed, oilseed and grain (Cope &
Gray, 2009). Grain imports to Great Yarmouth are
from locations outside the native range of Eremopoa
persica. The most likely scenario, given the urban
location in which the Great Yarmouth plant was
found, is that it arrived in the town quite recently
as a contaminant of birdseed. Around half of the
world’s production of sunower, one of the eleven
types of seed most frequently occurring in birdseed
mixtures, is grown in the Ukraine and Russia, within
the native range of Eremopoa persica.
Conclusion
This is the first record of Eremeopoa persica for
Norfolk and the rst for the UK for over half a
century. Unlike the historic records, which are likely
associated with wool imports, the Great Yarmouth
plant is probably a bird seed alien. Given the rate at
which other non-native grasses from warmer climes
have spread in recent years (Pescott & Baker, 2014),
and the popularity of bird-feeding, this may be a
species that recorders should have on their radars.
Acknowledgements
Fred Rumsey and John Hunnex for locating
and providing the image of the British Museum
specimen. Rhian Rowson for locating specimens
within the Bristol Museum herbarium. The
Smithsonian Institution for permission to reproduce
an illustration from Grasses of Egypt. The British
Museum for permission to reproduce an image of
an herbarium specimen.
References
Clayton, W.D. 1990. The spikelet, in G.P. Chapman (ed),
Reproductive Versatility in the Grasses. Cambridge University
Press, Cambridge, pp. 32–51.
Clayton, W.D. & Renvoize, S.A. 1986. Genera Graminum: Grasses
of the World. Royal Botanic Gardens, Kew.
Cope, T. & Gray, A. 2009. Grasses of the British Isles, BSBI
Handbook No. 13. Botanical Society of the British Isles,
London.
Gillespie, L.J., Soreng, R.J., Cabi, E., & Amiri, N. 2018.
Phylogeny and taxonomic synopsis of Poa subgenus
Pseudopoa (including Eremopoa and Lindbergella)
(Poaceae, Poeae, Poinae). Phytokeys 111: 69–102.
Greuter, W., Heywood, V., Jury, S., Marhold, K., Pertti U. &
Valdés B. (eds) 1984–2011. Euro+Med PlantBase: www.
emplantbase.org/home.html [accessed 5 February 2021].
Ibrahim, K.M., Hosni, H.A. & Peterson, P.M. 2016. Grasses
of Egypt. Smithsonian Institution, Washington.
Missouri Botanical Garden, 2021. Online Flora of Pakistan:
http://legacy.tropicos.org/Project/Pakistan [accessed 4
February 2021].
Pescott, O. & Baker, A. 2014. Alien grasses in urban Sheeld:
An update on Water Bent and some predicted colonists.
Sorby Record 50: 62–65.
Portal, R., & Duhem, B. 2002. Eragrostis de France et de l’Europe
Occidentale. Portal, Vals-près-le-Puy.
Rahmanian, S., Saeidi, H., Assadi, M. & Rahiminejad, M.R.,
2014. A taxonomic revision of the genus Eremopoa Roschv.
(Poaceae, Poeae) in Iran. Iranian Journal of Botany 20: 8–15.
Ryves, T.B., Clement, E.J. & Foster, M.C. 1996. Alien grasses
of the British Isles. Botanical Society of the British Isles,
London.
Soreng, R.J., Olonova, M.V., Probatova, N.S. & Gillespie,
L.J. 2020. Breeding systems and phylogeny in Poa, with
special attention to Northeast Asia: The problem of Poa
shumushuensis and sect. Nivicolae (Poaceae). Journal of
Systematics and Evolution: https://doi.org/10.1111/jse.12647
Stace, C.A. & Crawley, M.J. 2015. Alien Plants. William
Collins, London.
Stace, C.A. 2019. New Flora of the British Isles (4th edn).
C & M Floristics, Middlewood Green, Suolk.
Verloove, F. 2006. Catalogue of neophytes in Belgium (1800–
2005). Scripta Botanica Belgica 39: 1–89. www.researchgate.
net/publication/287920501_Catalogue_of_neophytes_in_
Belgium_1800–2005
Bob Leaney
122 Norwich Road, Wroxham, Norwich NR12 8SD
Jo Parmenter
The Landscape Partnership, Holland Court,
Norwich NR1 4DY
jo.parmenter@tlp.uk.com
Oli Pescott
BSBI Referee for alien grasses
UKCEH, Wallingford, OX10 8BB
olipes@ceh.ac.uk
ADVENTIVES AND ALIENS: Eremopoa persica re-found in Britain after a 60-year absence
