Günther's Site - Photos of European Plants


Hybrid clans between Whitebeam and Wild Service Tree


Whitebeam Sorbus aria ( as well as the closely related Hill Whitebeam Sorbus collina in the Franconian Alb resp. Tauber Whitebeam Sorbus dubronensis in the Tauber region, and Balkan Whitebeam Sorbus graeca in Eastern Europe ) are able to generate hybrids if they occur together. In several regions such hybrids have developed to stabilized and hereditary-stable hybrid clans, with different appearance in different regions although they have the same parents. In their regions they form smaller or bigger populations, which botanists today are treating as closely related species. In Germany a cumulation of such hybrid clans can be observed in parts of Franconia together with adjacent regions of Bavaria around Regensburg, of Baden-Württemberg in the Tauber region, and of Thuringia. But also in other countries as e.g. France, the British Islands, Scandinavia and Eastern European Countries there are hybrid clans between Whitebeam and Wild Service Tree. Attributes as the different forms of the parents' leaves, the pubescence of the bottom side of Whitebeam's leaves which the Wild Service Tree doesn't have, the figure of the tree, and more attributes of the parents are intermediate in any way at the hybrid clans, but more or less different at each of them. In the spring the leaves of many clans have a slight pilosity also at the top side, a heritage of Whitebeam, which they lose during the summer, when the leaves become more coriaceous. The hybrid clans of which I have already taken photos are presented by showing the different forms of their leaves. A few years ago, the hybrid clans between Whitebeam and Wild Service Tree were re-combined into the separate genus Karpatiosorbus.
Sorbus aria / Whitebeam Rosaceae / Rose Fam. parent	Sorbus collina / Hill Whitebeam Rosaceae / Rose Fam. parent	Sorbus dubronensis / Tauber Whitebeam Rosaceae / Rose Fam. parent
Sorbus torminalis / Wild Service Tree Rosaceae / Rose Fam. parent	Sorbus latifolia s.l. / Broad-Leaved European Mountain-Ash Rosaceae / Rose Fam. Weinheim an der Bergstraße	Sorbus latifolia s.l. / Broad-Leaved European Mountain-Ash Rosaceae / Rose Fam. Idar-Oberstein
The Broad-Leaved European Mountain-Ash in narrow sense comes from the region around Paris, elsewhere it is also grown in parks. The Broad-Leaved European Mountain-Ashes from the Nahe / Hunsrueck / Rheinhessen region haven't got own names (yet). It seems that they are not unique, but seem to have developed at several places. The leaf forms of some of these are closer to the type population from Paris than the one from a garden at Weinheim shown above in the middle.
Sorbus moenofranconica / Main-Franconian Whitebeam Rosaceae / Rose Fam. Erlenbach near Marktheidenfeld	Sorbus meyeri / Meyer's Whitebeam Rosaceae / Rose Fam. Tauber Region, Kuelsheim	Sorbus koksensis / Koks Whitebeam Rosaceae / Rose Fam. Tauber Region, Kuelsheim
Sorbus badensis / Baden Whitebeam Rosaceae / Rose Fam. Tauber Region, Koenigheim	Sorbus seyboldiana / Seybold's Whitebeam Rosaceae / Rose Fam. Tauber Region, Werbachhausen	Sorbus puellarum / Girlish Whitebeam Rosaceae / Rose Fam. Franconia, Uettingen
Sorbus haesitans / Thuengersheim Whitebeam Rosaceae / Rose Fam. Franconia, Thuengersheim	Sorbus perlonga / Long-Leaved Whitebeam Rosaceae / Rose Fam. Franconia, Leinach NW Wuerzburg	Sorbus herbipolitana / Wuerzburg Whitebeam Rosaceae / Rose Fam. Franconia, Guentersleben near Wuerzburg
Sorbus schnizleiniana / Schnizlein's Whitebeam Rosaceae / Rose Fam. Franconia, Neukirchen	Sorbus adeana / Ade's Whitebeam Rosaceae / Rose Fam. Franconian Alb, Weismain	Sorbus cordigastensis / Kordigast Whitebeam Rosaceae / Rose Fam. Franconian Alb, Weismain, Großer Kordigast
Sorbus franconica / Franconian Whitebeam Rosaceae / Rose Fam. Franconia, Ebermannstadt	Sorbus meierottii / Wellheim Whitebeam Rosaceae / Rose Fam. Wellheim in Urdonau Valley	Sorbus eystettensis / Eichstaett Whitebeam Rosaceae / Rose Fam. Eichstaett
Sorbus schuwerkiorum / Schuwerk's Whitebeam Rosaceae / Rose Fam. Greding	Sorbus ratisbonensis / Regensburg Whitebeam Rosaceae / Rose Fam. Undorf near Regensburg	Sorbus mergenthaleriana / Mergenthaler's Whitebeam Rosaceae / Rose Fam. Etterzhausen near Regensburg
Sorbus hoppeana / Hoppe's Whitebeam Rosaceae / Rose Fam. Krachenhausen near Kallmuenz	Sorbus fischeri / Ries Whitebeam Rosaceae / Rose Fam. Noerdlinger Ries, Harburg in Schwaben	Sorbus slovenica / Slovakian Whitebeam Rosaceae / Rose Fam. Austria, Hundsheim Mountain
The following clans, which formerly had been described as species, are all diploid and not apomictic, they all propagate sexually. So today they all are taken as synonyms of Sorbus x decipiens ( = Karpatiosorbus x hybrida).
Sorbus cochleariformis / Spoon-Leaved Whitebeam Rosaceae / Rose Fam. Franconia, Untererthal	Sorbus x vagensis / Hybrid Service Tree Rosaceae / Rose Fam. Franconia, Leinach NW Wuerzburg	Sorbus acutisecta / Acute-Lobate Whitebeam Rosaceae / Rose Fam. Hessen, Treffurt
Sorbus isenacensis / Eisenach Whitebeam Rosaceae / Rose Fam. Thuringia, Eisenach	Sorbus multicrenata / Many-Scored Whitebeam Rosaceae / Rose Fam. Thuringia, Bad Blankenburg	Sorbus heilingensis / Heilingen Whitebeam Rosaceae / Rose Fam. Thuringia, Kleinbucha
Sorbus subcordata / Arnstadt Whitebeam Rosaceae / Rose Fam. Thuringia, Arnstadt	Sorbus x decipiens / Sharp-Toothed Whitebeam Rosaceae / Rose Fam. Thuringia, Waltershausen
Naturally this list isn't complete. It will be continued on occasion. The botanical garden of the University of Regensburg grows a remarkable collection not only of Sorbus trees, but also of other members of the Rose family, mainly Brambles, Hawthorns and native Roses. Hybrid clans between Whitebeam Sorbus aria and Rowan Sorbus aucuparia you can find here.