Do you have any introduced tree species in the forests you manage? If yes, does the management differ to that with native tree species? If not, would you consider using introduced tree species?
Yes, we grow many non-native tree species (Pseudotsuga menziesii, Juglans nigra, Platanus acerifolia, Gleditsia triacanthos, Robinia pseudacacia, Quercus rubra, …). The management does not differ from native species except Robinia and Ailanthus. With the latter we do not encourage natural regeneration.
Although Austria doesn’t have a large proportion of introduced tree species, do you think this will change over time bearing in mind climate change?
Yes, I think so, mainly outside the Alpine region, i.e. in the Northeast and Southeast of Austria. In the Alps there is an abundancy of native species available even in a changing environment.
What do you consider as the major challenges and opportunities of introduced tree species?
- Better adaptation to sites, particularly in a changing environment and on dry sites
- Economic diversification, risk management
- Increasing biodiversity
- Unpredictable interaction with other species and ecosystem (except well-known species like Pseudotsuga menziesii, Juglans nigra, …)
- Unknown pests
- Small, volatile and slowly developing markets
Do you think that invasive potential of introduced tree species in general is considered at the time of their introduction?
In forestry mostly yes, because of professional background. In private and communal gardening not at all. In landscape management only recently.
Do you think introduced tree species can be used in close-to-nature forest management? What is your experience with this?
Of course. With growing experience in using a non-native tree species the understanding of ecosystem interactions improves. Necessity and intensity of human intervention decrease. Close-to-nature forest management then becomes an option.
Dr. Herbert Tiefenbacher
Senior forest manager
Grafenegg Forest Estate