It might seem odd to start a new series with a tree few have heard of (I certainly hadn’t until a few weeks past) but recently, I’ve been bumping into the unassuming Sorbus mougeotii quite a bit in my local area.
Looking similar to the Swedish Whitebeam (Sorbus intermedia), at least to my untrained eye, Mougeot’s Whitebeam (Sorbus mougeotii) is a popular choice for landscapers and here in Newcastle, appears to be widely planted in parks and on reclaimed land. But not always…
The tree shown below was encountered in what appeared to be a wild setting, growing on the Banks of the River Tyne between Newburn and Wylam. In contrast to other local sites, no others were observed nearby.
Background
The genus name, Sorbus, identifies this plant to family while its species name, mougeotii, refers to French botanist, Jean-Baptiste Mougeot.
Sorbus mougeotii is a moderately sized whitebeam native to the mountains of central and western Europe, from the Pyrenees to the Vosges. Its presence at the latter giving rise to its alternate name of Vosges Whitebeam. It was described in 1858 but wasn’t brought truly into cultivation until the 1950s by the Danish Health Society, and was originally marketed as a cultivar of Swedish Whitebeam.
This tree is widely grown as an ornamental in Northern Europe due to its tolerance of difficult growing conditions, including urban habitats and poor soil. For this reason, it is often used as part of land reclamation schemes.
A closer look at the BSBI distribution map for this species would suggest that it is rarely encountered in the UK, though its similarity to other whitebeams means it is almost certainly under-recorded. Indeed, since having this species pointed out to me, I have noticed it at a total of six sites in only a few weeks.
An interesting paper on the discovery of Sorbus mougoutii and its potential as an invasive species in Ireland can be found here.
Identifying Mougeot’s Whitebeam
A deciduous, multi-stemmed tree growing to approximately 10m, Mougeot’s Whitebeam is most closely related to some of the rare and endemic British whitebeam species, most notable the English Whitebeam, Sorbus anglica. Indeed, the only difference between the two is said to be the slightly broader leaves of the former species.
English Whitebeam is a scarce species in the UK and oddly enough given its name, is found predominately in Wales. There are no records in the North of the UK meaning that up here, Mougeot’s Whitebeam is most likely to be confused with the much more abundant Swedish Whitebeam. A tree that is both naturalised and routinely planted across the UK.
Separating these two species is a fun task but can be done, with the leaves of Mougeot’s Whitebeam differing from its Swedish counterpart in being more shallowly lobed in most cases. These lobes also point forward, something I’ve found to be incredibly helpful given how just about every other feature associated with this species seems to vary considerably!
In Swedish Whitebeam, the same lobes are spreading. There is also said to be a difference in the underside of the leaves too with those of Mougeot’s Whitebeam covered in dense white hairs and those of Swedish Whitebeam only slightly hairy. Alas, I’ve struggled to see the difference!
One thing I have also noticed from plants confirmed to be Mougeot’s Whitebeam is that the mid-rib, the central vein running down the leaf, appears yellowish on the underside. That said, I can find nothing about this online and may have made it up…
Finally, the fruits of Mougeot’s Whitebeam are said to be less bright red than those of Swedish Whitebeam but again, this seems to be subjective.