The oak tree clearance in German mixed forests over the last centuries shows fatale long term consequences. The result is instable pure pine tree stands, which are very vulnerable for forest fires and insect damage. The STEIN TASK-FORCE planted 2.000 young oak trees in the course of a planting campaign and built a 400 meter long fence around it to protect the trees from insects. With this action part of the pine tree forest in the nature reserve Lüneburger Heide was upgraded to a common oak tree forest. Therefore the forest conversion was speeded up in favor of natural forest vegetation.