Cotoneaster x suecicus G. Klotz, Beitr. Phytotax. 10: 47, 1982.
Section Alpigeni, series Conspicuus x series Radicantes
Origin: an artificial hybrid (unknown in the wild), probably of Cotoneaster conspicuus J.B. Comber ex C. Marquand and C. dammeri C.K. Schneider (Flinck & Hylmö 1967).
Presence in western Europe: Naturalized in Great Britain (Stace 2010). Furthermore known from France (Farille & al. 2010), Germany (Dickoré & Kasperek 2010), Luxembourg (LG!; sub C. dammeri), Scandinavia (Karlsson 2002).
Cultivation in Belgium and the Netherlands: “rare” (De Koning & van den Broek 2009). This is rather surprising and possibly erroneous. Some of its cultivars (especially cv Coral Beauty) are among the most frequently planted low-growing cotoneasters (see also Fryer & Hylmö 2009, Farille & al. 2010). Compare also with Roloff & Bärtels (2006; “sehr häufig”). According to De Koning & van den Broek l.c. Cotoneaster conspicuus (one of its parents) is commonly cultivated in the Netherlands and Belgium. In fact, it may be that part of this belongs with C. xsuecicus. Genuine Cotoneaster conspicuus is possibly rather rare in cultivation in western Europe and, at least in Central Europe, probably not fully hardy (Klotz 1957).
Comparative taxonomy: Dickoré & Kasperek (2010) include Cotoneaster conspicuus in C. integrifolius (Roxburgh) G. Klotz and therefore give the latter and C. dammeri as putative parents. Cotoneaster xsuecicus is unknown in the wild and logically is not included in Flora of China (Lingdi & Brach 2003).
Illustrations: Roloff & Bärtels (2006), De Koning & van den Broek (2009), Fryer & Hylmö (2009), Stace (2010).
Cotoneaster xsuecicus is a rather rare escape from cultivation in Belgium and probably nowhere genuinely naturalized (yet). It was first documented from the ruins of the Lapidarium in the city of Ieper (a single shrub since 2006 and subsequently regularly confirmed). Also in 2006 it was collected on a rocky talus slope near Liège (Sart Tilman; sub C. dammeri), possibly as a mere relic of cultivation. Cotoneaster xsuecicus was found in 2009 on top of a wall near the church of Westende and in 2010 under birch trees on an artificial chalk deposit in Lauwe (Wevelgem). In 2011 furthermore recorded in Menen (top of old wall at the cemetery) and in coastal dunes in Oostduinkerke. Possibly overlooked elsewhere (plants are often rather unshowy!) or confused with similar species (especially Cotoneaster dammeri or C. integrifolius).
It is a fully fertile hybrid that reproduces sexually (see also Dickoré & Kasperek 2010; Farille & al. 2010).
Cotoneaster xsuecicus seems to be confined to dry, half-shady or sun-exposed and often gravelly habitats, mostly on calcareous substrates. So far, it has been recorded on top of old walls, under scrub in coastal dunes and, exceptionally, on artificial chalk deposits or on gravely talus slopes.
This species is one of the few species in Belgium with evergreen leaves, patent white petals and (semi-) procumbent, rooting branches. It most closely resembles Cotoneaster dammeri, one of its parents, and both have been widely confused in Belgium so far. However, it always has smaller leaves, only 2-4 nutlets per berry (not 5) and it usually has at least some branches that are ascending (not all carpeting). See under Cotoneaster dammeri for more details. Cotoneaster xsuecicus is a very variable taxon with numerous cultivars (see Fryer & Hylmö 2009). It furthermore looks like Cotoneaster integrifolius (and related species from series Microphylli many of which are aggregated under the latter by Dickoré & Kasperek 2010). Both are opposed in the table beneath
|
C. xsuecicus |
C. integrifolius |
|
Inflorescence with 2-6 flowers |
Flowers solitary (rarely 2) |
|
Leaves up to 23 mm long |
Leaves up to 17 mm long |
|
Berry with 2-4 stones |
Berry with 2 stones (rarely 3) |
|
Stamens 15-20 |
Stamens 20 |
|
Branches (semi-) procumbent with at least some branches rooting, up to 60 cm tall |
Branches suberect-decumbent, never rooting, to 150 cm tall |
Literature
De Koning J. & van Den Broek (2009) Nederlandse Dendrologie (14th ed.). K.N.N.V.: 547 p.
Dickoré W.B. & Kasperek G. (2010) Species of Cotoneaster (Rosaceae, Maloideae) indigenous to, naturalising or commonly cultivated in Central Europe. Willdenowia 40: 13-45 [available online at: http://user.uni-frankfurt.de/~kasperek/papers/dickore_kasperek_2010.pdf].
Farille M.A., Zeller J., Jordan D., Charpin A. & Garraud L. (2010) Cotoneasters échappés de jardins en Haute-Savoie. Monde Pl. 501: 1-5.
Flinck K.E. & Hylmö B. (1967) Cotoneaster i Svensk odling. Lustgarden 5.
Fryer J. & Hylmö B. (2009) Cotoneasters. A comprehensive guide to shrubs for flowers, fruit, and foliage. Timber Press, Portland-London: 344 p.
Karlsson T. (2002) Nyheter i den svenska kärlväxtfloran II. Korsblommiga–flockblommiga. Svensk Botanisk Tidskrift 96: 186-206. [available online at: http://sbf.c.se/www/pdf/96(3-4)/Karlsson.pdf]
Klotz G. (1957) Übersicht über die in Kultur befindlichen Cotoneaster-Arten. Wiss. Z. Univ. Halle, Math.-Nat. 6(6): 945-982.
Lingdi L. & Brach A.R. (2003) Cotoneaster. In: Wu Z.Y. & Raven P.H. (eds.), Flora of China, vol. 9. Science Press, Beijing & Missouri Botanical Garden Press, St. Louis: 85-108 [available online at: http://flora.huh.harvard.edu/china/PDF/PDF09/Cotoneaster.PDF].
Roloff A. & Bärtels A. (2006) Flora der Gehölze (2e Auflage). Ulmer, Stuttgart: 844 p.
Stace C. (2010) New Flora of the British Isles, 3th ed.: XXXII + 1232 p. Cambridge University Press.