Background
Tree-lined roads are a hallmark of Central Europe. Since the early 18th century, the kings of Prussia mandated the planting of trees along every road of their realm. Today these avenues through the agricultural landscapes of eastern Germany and western and northern Poland are mainstays of biodiversity. One of most celebrated inhabitants of roadside trees is the hermit beetle, an animal protected by the EU?s Habitat Directive as a priority species (just like the wolf and the brown bear). In the past, this species inhabited primeval forests, its larvae foraging inside old hollow trees. Now, its survival depends on these avenues. Being a poor flier, it uses rows of trees as ecological corridors, migrating from one to another and thus maintaining ecological connectivity between populations.

Nowadays, many roadside trees are giving way to road upgrade; very few are being planted to restore this vital resource. The need for infrastructure development and traffic safety improvement is understandable. However, improved transport capacity should not happen at the expense of our natural and cultural heritage. Far too many trees are being cut unnecessarily due to rash, arbitrary decisions made without considering viable alternatives. If the loss of roadside trees continues at current pace, the hermit beetle will soon be lost. Conservationists have been very vocal in protesting the removal of old roadside trees. The issue, however, has elicited very little meaningful dialogue between diverse parties seeking a lasting solution.

Solution
The good news is that there is still room for both cars and trees along Polish roads. Many roads, even after improvements, still have space available to replant trees. Trees on many other roads can even be preserved when other safety measures are applied, such as barriers, trunk markings, or speed limits. These methods have already been successfully implemented in Germany and other countries.

The Roads for Nature project sets a framework for forming successful partnerships between road maintenance service providers, conservationists and local authorities. A number of roads where tree replanting is feasible have already been identified. Priority is given to routes that can serve as ecological corridors for the hermit beetle. A pilot project was launched in 2008 north of Wroclaw along a three kilometre-long route where a tree-lined avenue is being restored by a coalition of road management office, community activists and conservationists.

These positive results have created new opportunities for more and more tree-lined avenues to be restored or saved. Corporate efforts to couple carbon offsetting with landscape restoration and biodiversity conservation make way for significant private-sector involvement in the initiative.

Trees, not borders
A new transnational avenue is currently in the planning phase at a crossing point between Poland and Germany, near Zgorzelec/Goerlitz. This high-profile initiative not only celebrates borders that join nations, it also educates the general public and local authorities about the significance of tree-lined avenues for the natural world, our rural landscapes and our quality of life. Local authorities in Poland have already granted permission for the plantings. Consultations with German authorities are currently under way. A presentation of the initiative during a joint meeting of environment ministers from Poland and Germany and was enthusiastically received. We will work to have the ministers not only as patrons of this event, but also as main participants.