Festuca trachyphylla (Hackel) Krajina, a grass introduced into the Suffolk Breckland

FESTUCA TRACHYPHYLLA (HACKEL) KRAJINA, A GRASS INTRODUCED INTO THE SUFFOLK BRECKLAND P . J. O . TRIST

Festuca trachyphylla may not b e k n o w n to m a n y p e o p l e and those w h o k n o w this grass, m a y k n o w it by a n o t h e r n a m e . Its n o m e n c l a t u r e has been c o n f u s e d for a long time and t h e p u r p o s e of this n o t e is to clarify t h e Situation.

F. trachyphylla is a t u f t e d p e r e n n i a l a n d o n e of o u r earliest fescues. It is in flower by mid M a y and the panicle is b r e a k i n g u p by mid J u n e . Its height is variable f r o m 1 0 - 6 0 c m . T h e leaves a r e generally a dark glossy green but occasionally a little glaucous, minutely hairy in t h e lower p a r t , as is also the sheath which is o p e n to the b a s e . T h e panicle is a d a r k green or d a r k m a u v e , with the b r a n c h e s a n d pedicels scabrid. T h e l e m m a is a w n e d l - 4 - 2 - 5 m m in length. T h e r e is a wide Variation in t h e length of t h e spikelet, l e m m a and glumes, a n d this fescue c a n n o t be d e t e r m i n e d on these m e a s u r e m e n t s . It is frequently growing with Festuca rubra ( R e d Fescue) f r o m which it m a y be separated by t h e absence of rhizomes a n d extra vaginal shoots.

Distribution M a r k g r a f - D a n n e n b e r g (1980) gives F. trachyphylla as a native of C e n t r a l E u r o p e , e x t e n d i n g to B e l g i u m , and is widely naturalized e l s e w h e r e . H u b bard (1968) r e p o r t s that 'it was p r o b a b l y i n t r o d u c e d into Britain d u r i n g the 19th Century by seed i m p o r t e d f r o m G e r m a n y ' . In S u f f o l k , v.c. 26, it is only f o u n d in t h e B r e c k l a n d a r e a . It is m o r e than likely that it was i n t r o d u c e d during t h e late war w h e n t h e B r a n d o n - L a k e n h e a t h r o a d was diverted f r o m t h e site n o w occupied by the U S A F Base at W a n g f o r d . O n this r o a d which crosses W a n g f o r d F e n , F. trachyphylla is a b u n d a n t o n t h e sandy grass road verge for c. 4 0 0 m , and here I suspect it was i n t r o d u c e d in t h e verge seeding. It has spread to t h e verges of t h e main A1065 f r o m W a n g f o r d all t h e w a y to the e n t r a n c e track into L a k e n h e a t h W a r r e n . It is also f o u n d on t h e a d j a c e n t airfield and on t h e small grassed area b e h i n d the car p a r k of the shops at t h e west end of L o r d ' s W a l k , Little Eriswell.

It is noticeable that although a strong grass, it p r e f e r s o p e n situations and in loose well d r a i n e d sand. It is clearly d r o u g h t resistant and is t h e r e f o r e suited to t h e coarse sand and t h e low rainfall of t h e B r e c k l a n d . In n o a r e a has it f o r m e d a c o m p a c t sward b u t it quickly colonizes grass verge a r e a s s w a m p e d by wind e r o d e d sand. Its associates a r e w e a k and small plants and include Cerastium arvense (Field M o u s e - e a r ) , Vulpia bromoides (Squirrel-tail G r a s s ) , Aira praecox (Early Hair G r a s s ) and Bromus sterilis ( B a r r e n B r o m e ) . O n n u m e r o u s searches on t h e W a n g f o r d verges, n o plants of this fescue h a v e b e e n f o u n d on t h e arable or h e a t h a d j a c e n t t o the verge.

Nomenclature F. trachyphylla

is o n e of several fescues of t h e Festuca ovina ( S h e e p ' s Fescue)

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aggregate, the taxonomy of which has until comparatively recently been little understood and the nomenclature confused. Hubbard (1968) refers F. trachyphylla to F. longifolia, Tutin (1952) gives F. longifolia and F. duriuscula auct. as synonyms of F. trachyphylla, while Dandy (1958) gives F. longifolia preference with F. trachyphylla and F. duriuscula as synonyms.

Research work of the 1970's gradually unfolded the confusion. In 1972, I referred specimens of this taxon from Breckland sites to the late Dr Hubbard who identified them as Festuca longifolia but it was later to be revealed that this name was misapplied. At this time, the late Dr Auquier of Liege was working on the F. ovina aggregate and, at his request, specimens of the Breckland taxon then referred as Festuca glauca Lam. var. caesia (Sm.) K. Rieht. (Grey Fescue), were sent to him. At the same time, Auquier turned his attention to Festuca glauca which was credited to two authors, namely Villars and Lamarck. Auquier (1977) found that the date of publication of F. glauca by Villars preceded the publication of F. glauca by Lamarck. At this time, Trist (1973) had concluded that F. glauca var. caesia was only a depauperate form: and as F. glauca Villars took precedence, Auquier considered that the remaining taxon should be afforded specific rank as Festuca caesia Sm., its earlier name.

Auquier (1973) had already established that F. caesia of the Breckland sands was similar to the glaueous plants of the sands of Lower Normandy, and later in 1977 he reported that similar plants were widely distributed in the Paris Basin and in Central France. Furthermore, a description of this glaueous fescue was identical with the original description of Festuca longifolia published by Thuillier (1799). The Breckland taxon is therefore F. longifolia.

We now turn to Hubbard (1968) and, under the name of F. longifolia Thuill., we find a description of a taxon which does not answer to that name as now understood. What was the taxon meant? According to the results of work being carried out at Leicester University by Mike Wilkinson, Hubbard's description of F. longifolia is considered to refer to F. trachyphylla plus a related species, F. lemanii Bast. Both occur in Britain, and Hubbard's figure of the leaf section at least is unequivocally F. lemanii rather than F. trachyphylla. But, alas! Festuca trachyphylla (Hackel) Krajina is nom. illeg.

Investigations are proeeeding and a new name will eventually be found.

Acknowledgment I am grateful to Prof. Clive Stace for guidance on the morphology of F. trachyphylla.

References Auquier, P. (1973). Qu'est-ce que Le Festuca caesia Sm. (Poacae)? Lejeunia, 70. Liege.

Auquier, P. & Kerguelen, M. (1977). Un groupe de Festuca (Poacae): les taxons designes par l'epithete 'glauca' en Europe occidentale et dans les regions voisines. Lejeunia, 89. Liege.

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A GRASS INTRODUCED INTO THE SUFFOLK BRECKLAND

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Dandy, J. E. (1958). List of British vascularplants, London.

Hubbard, C. E. (1968). Grasses, Harmondsworth.

Markgraf-Dannenberg, I. (1980). Festuca trachyphylla (Hack.) Krajina, in Tutin, T. G. etal., (eds.) Flora Europaea, 5, Cambridge.

Thuillier, J. L. (1799). Lafloredes environs de Paris. Paris.

Trist, P. J. O. (1973). Festuca glauca Lam. var. caesia (Sm.) K. Rieht.

Watsonia, 9.

Tutin, T. G. (1952). Festuca trachyphylla, in Clapham, A. R., Tutin, T. G. and Warburg, E. F. Flora ofthe British Isles. Cambridge.

P. J. O. Trist, Glovers 28 High Street, Balsham, Cambridge CB1 6DJ

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