This paper presents the preliminary results of field investigations, studies on natural succession at timberline, and discussions on practical experience aimed at identifying causes of success or failure in high altitude afforestations (30 and 80 years old) in Austria and Switzerland. The findings so far reveal the following implications for future projects:
Planning:
- long-term 'High Altitude Development Plans' on a local and regional basis are essential
- digital mapping and superimposition of natural site factors (altitude, exposure, inclination, plan communities, ground relief etc.) should shortly be possible
Preparation:
- autochthonous seed from (a few) locally growing individuals should be used
- plants should be raised without excessive or unbalanced fertilisation under climatic conditions corresponding as closely as possible to those of the prospective planting site
- planting sites should be carefully selected with regard to altitude, exposure, inclination, ground relief, soil type and depth, ground cover, plant communities, soil erosion and local natural tree vegetation
- planting holes should be prepared 2-5 years in advance
Execution:
- careful pit-planting in groups is necessary
- the young trees must be adequately protected against damage by cattle, wild animals, and skiers
Tending:
- all infected individuals should be consistently removed
- gaps should be filled (beating up)
- compact adult groups should be thinned to create stable units
It is recommended that a model afforestation be established to demonstrate and confirm the results of scientific studies and practical experience.