Agrostis x fouilladeana Lambinon et Verloove (A. capillaris x A. castellana) (Eur., N-Afr., W-As.) – Increasingly found naturalised in newly sown road verges, off-ramps and lawns, also in ruderal areas, dumps, coalmine heaps, sand-raised sites, railway yards and other man-made habitats. First reported from Roeselare in 1998 (Lambinon & Verloove 2000). A revision of herbarium collections of Agrostis capillaris f. aristata Lindm. yielded an earlier record from Edegem in 1991 (meadow at Fort V). At present known from numerous locations in Flanders. Surely much overlooked and insufficiently known.
This nothotaxon appears to be frequently sown, deliberately or undeliberately intermixed with native Agrostis capillaris. Through commercial selection it has become extremely variable, most variants being closer to Agrostis capillaris. Rather few populations approach genuine Agrostis castellana. Most European records of Agrostis castellana outside its original distribution range are probably referable to A. xfouilladeana (see also discussion in Edgar & Forde 1991).
Agrostis xfouilladeana is not always easily distinguished from awned forms of A. capillaris. In the latter the awn appears to be variable and can be straight, inserted in the upper half of the lemma (subapically) and barely exceeding the glumes as well as inserted in the lower half, more or less geniculate and exceeding the glumes. In the latter case the hairy callus and the excurrent lateral nerves of the lemma of Agrostis xfouilladeana are diagnostic. Agrostis xfouilladeana has geniculate awns inserted at the base of the lemma that much exceed the glumes. The distinction of Agrostis xfouilladeana and A. castellana is also often problematic. The latter usually has more scabrous pedicels, lateral nerves that are longer excurrent, longer callus hairs and a more branched inflorescence (panicle branches branched up to three times and without spikelets in the lower ½).
Selected literature:
Batson M.-G. (1998) Agrostis castellana (Poaceae), Dominant Agrostis Species, found in Bent Grass Pastures in South-eastern Australia. Aust. J. Bot. 46: 697-705.
Edgar E. & Forde M.B. (1991) Agrostis L. in New Zealand. New Zealand Journal of Botany 29: 139-161.
Kurrto A. (2007) Lisää etelänröllistä. Lutukka 23: 116-119.
Lambinon J. & Verloove F. (2000) n° 19853 Agrostis x fouilladei P. Fourn., nom. nudum (?). In: Notes brèves sur certains centuries distribuées dans le fascicule 28. Soc. Ech. Pl. Vasc. Eur. Bass. Médit., Bull. 28: 104-105.
Lambinon J., Verloove F. & Toussaint B. (2004b) Agrostis x fouilladeana, nothospec. nov., en Belgique et dans le nord de la France. Soc. Ech. Pl. Vasc. Eur. Bass. Médit., Bull. 29: 105-109.
Macfarlane T.D. & Williams A.R. (2007) Agrostis castellana (Poaceae) mis-identified as A. capillaris var. aristata in Western Australia. Nuytsia 16(2): 472.
Melzer H. (1993) Über Amaranthus bouchonii Aellen, Bouchons Fuchsschwanz, Agrostis castellana Boissier et Reuter, das Kastilische Straussgras und andere bemerkenswerte Blütenpflanzen Kärntens. Carinthia II 103(2): 715-722.
Scholz H. (1962) Agrostis castellana: eine neue Fremdpflanze in Schleswig-Holstein. Die Heimat 69: 405-406.
Scholz H. (1965) Agrostis tenuis ‘Highland Bent’ ein Synonym der Agrostis castellana. Ber. Dtsch. Bot. Ges. 78: 322-325.
Shildrick P.J. (1977) Highland bent: a taxonomic problem. Sports Turf Res. Inst. J. 52: 142-150.