BUND Mecklenburg-Vorpommern and Drogi dla Natury launched a programme called "Make avenues, not borders". In 2014, the first German-Polish avenue was planted, as a symbol of European cohesion and peace.

Trees are powerful symbols. The two Korean leaders who are planting a tree on the boarder these days, as a "symbol of peace and prosperity", did understand this.

In 1922, French Marshall Joffre tourned the world to promote peace. In the United States, he planted one of the 1000 elms of the Des Moines Memorial Drive.