Wild Service Tree (Sorbus torminalis L.)– Tree of the Year 2011
The species awarded Tree of the Year 2011 is so rare that according to a recent questionnaire most people have never heard about it: it is the Wild service tree (Sorbus torminalis L.), also known as Checkers-tree or Chequers-tree. It could very well grow throughout Germany but it does not – a very good reason to draw some attention to this species by awarding it Tree of the Year. It is not the only reason, though: Its wood ranks among the noblest and most precious, its comparatively late blossoms are very attractive, its autumn colors fabulous, and delicious food can be made from its fruit.
What is a Wild service tree? most people will ask when you mention its name. Well, its leaves resemble those of a maple tree but if you take a closer look you will find that they are less regularly lobed. Indeed, the leaves of the Wild service tree vary in shape, with both their lowest lobes sometimes taking the shape of a heart at their base and spreading out more strongly than the other lobes, sometimes so strongly that they are actually separated from the rest of the leaf. The autumn colors are breathtaking, ranging from fiery red to bright yellow.
The Wild service tree grows short and long shoots. A short shoot chain can live up to 66 years – the highest avarage age I have ever found in short shoot chains, thus testifying to the impressive survival skills of a Wild service tree in the understory environment of a wood.
From the age of 30 the bark begins to peel away in squarish scales, giving the trunk its characteristic appearance. The bark is not unlike that of the pear, a tree it can easily be confused with in winter, but the buds are distinct in color and shape: brown and pointed in a pear, green and round in a Wild service tree.
The Wild service tree lives up to 200 or even 300 years and grows to 20-25m, sometimes 30m tall. Individual trees can be more than 1m in diameter – the largest tree I have ever seen in Germany grows on the Pehlitzwerder peninsula near Chorin (Brandenburg), its trunk is 1,10m in diameter.
On the other hand, some trees do not exceed the size of a shrub e.g. trees that have to resist the constant influence of wind as is the case at the coast – you simply have to admire their fighting power.
In Lower Austria, about 50 km west of Vienna around Michelbach, there is a unique landscape, the “land of the Wild service tree” the inhabitants proudly call it, where the species is not only well-known but celebrated every year on the second Sunday of May: In the market hall of Michelbach you are offered various products made from or related to the tree: pieces of art, wood work, food and the like. Lectures are held and walking tours take you to the most beautiful trees of the area (see www.elsbeerreich.at). There even is a very active association dedicated to the “conservation, cultivation and commercialization of the Wild Service Tree”. The tree is so important a part of the local identity that a filling station attendant might close down his shop to show you the most wonderful examples he knows – In Germany there is a support group as well, founded in 1993 to organize events promoting the Wild service tree (www.corminaria.de).
Freestanding trees begin to flower from the age of 20-25. The flowering season ends between the end of May and the beginning of June. The tree depends on cross-fertilization but even then about 80% of the ovules die. In case of self-fertilization, none survives.
The fruit owes the shape of its ovoid chalice to the epigynous ovary. Its flesh is grained like that of a pear due to stone cell nests. Its role in the natural rejuvenation process is insignificant – many seeds are eaten by mice, browsing often destroys the seedlings. But the Wild service tree has great sprout power, coppice and root shoot thus being by far the most powerful forces in reproduction. This is particularly true in the periphery of the distribution area. The species benefits from low and medium forest management as was common until the beginning of the 20th century.
Today, the Wild service tree ranks among the very rare tree species, single trees or small groups can be found in Germany but account for 1% of the woodland area only.
Translation: WIEBKE ROLOFF