In terms of timber utilisation, this tree species plays a secondary role to other deciduous species such as oak, beech, maple, ash or lime. And with maximum tree heights of 15 - 20 metres, the whitebeam is also quite small in comparison with other trees. However, when it comes to forest ecology, this species is a true giant! The whitebeam is extremely valuable in Bavaria, especially for forest nature conservation and structurally rich mountain forests.
Fig. 1: The whitebeam in autumn: fruit and leaves. Photo: Boris Mittermeier
The whitebeam is thus of great importance for bird protection in the forest. In studies carried out in England, 18 bird species were observed eating its reddish-coloured berries: the blackbird, song thrush, mistle thrush, redwing and fieldfare, robin, blackcap, starling, carrion crow, jay, magpie, wood pigeon, bullfinch, greenfinch, chaffinch and brambling, great tit and blue tit.
And on our native species of the Sorbus genus - whitebeams, wild service trees, rowans and service trees - researchers have so far been able to identify 157 herbivorous insect and mite species. This puts the Sorbus species in the bottom third in comparison with other native woody plants, but this may well be due to the fact that comparatively less research has been carried out on the Sorbus genus to date.
Fig. 2a and b: Whitebeam twigs with fruit and leaves (densely tomentose covered in white hairs on the underside). Photos: Christoph Josten
The main occurrences of the whitebeam in Bavaria are in the Alps and their foothills, where it finds good growing conditions up to an altitude of 1,500 metres above sea level. In the alpine mountain forest, the whitebeam is even the fourth most common deciduous tree species in forest regeneration after beech, sycamore and rowan, with a tree species share of approx. 4 %. A total of approx. 10,000 whitebeams were recorded in the regeneration on the approx. 200 inventory plots of the Bavarian protection forest restoration programme during the most recent surveys carried out by the LWF.
Whitebeams are however also to be found in the Franconian Jura and on the Franconian Plateau in Bavaria. By contrast, it is almost completely absent in the low mountain ranges of eastern Bavaria. Recently, especially from very dry areas in Lower Franconian forests, where beech, oak and pine are suffering particularly badly from drought stress, forestry practitioners have increasingly reported that the whitebeams still look vital and green. Although the LWF does not yet have any scientific data or facts on this subject, the reports of forest practitioners indicate that, due to its high level of drought tolerance, the whitebeam could play an important role in the forest of the future.
An interesting side note: The German word for whitebeam is “Mehlbeere”, meaning “flour berry”. It got this name from the fact that its ground seeds were sometimes added to flour in earlier times to stretch it or to make cakes and pastries sweeter.