Reading 6.2. Mitigation and Adaptation

In the Alpine Space, there are several billion trees of 135 native tree species (not all of them are considered forest trees from a legal point of view). By far the most common tree species is the spruce. It is considered the bread tree of forestry because it is not very demanding in terms of location, grows quickly, and its wood is versatile. However, because it has shallow roots, it needs a good water supply. Because many locations are becoming drier due to global warming, the spruce is increasingly losing habitat. However, not all is lost here. Forest owners can plant tree species that can cope better with the predicted conditions. This includes tree species that do not yet occur in the Alpine Space today. Climate change entails a change in tree species composition that would take several decades to occur naturally. Forestry can support the forest in this process and accelerate adaptation to climate warming through silvicultural measures.

The prerequisite for the positive effect of forest management is a site-adapted and sustainable approach. There are three good reasons for managing a forest:

  1. Targeted development of tree species composition
  2. Long-term carbon sequestration
  3. Replacement of fossil raw materials

For that to happen we need diverse, vital, and stable forests!

Forests that are fit for the future and fit for the climate have some special features: they are characterized by a diverse composition, have vital individual trees and stable stands. “Diverse” refers not only to the number of different tree species, but also to genetic diversity as well as the different ages and structural richness of the stand. Vital and stable stands are composed of healthy individual trees that have a strong root system, long and broad crowns, and a favorable H/D value.

The H/D value describes the relationship between the height and diameter (at breast height) of the tree. The smaller the H/D value, the more stable a tree is against natural events, such as storms.

The concept of climate-smart forestry does not only refer to the adaptation and development of stable forests with high resilience to climate change. It also takes into account the reduction and/or removal of greenhouse gases from the atmosphere and aims at sustainable timber production or its increase in order to secure the income generated from it in the long term.

But what can be done to make the forest “climate-smart”?

The strategy: Use development phases of the forest in time

The different development phases of a forest require different silvicultural measures. In this context, it is particularly important to take advantage of the silvicultural windows that open up in good time.

Measures that are not carried out or are carried out too late endanger the stability of the forest in the long term. For example, if timely (early!) stem number reduction or thinning is neglected in the young development stages of a stand, “thin” trees tend to form with short crowns, weak roots, and a high risk of wind, snow breakage, and beetle infestation. Failures in thicket management are difficult or impossible to compensate for in initial thinning.

Thinning should be carried out very vigorously and very early. Thinnings must be completed by half the rotation time.

For many measures, the involvement of forestry-trained personnel is strongly recommended!

In our project about climate-smart forestry in Austria ( we help foresters and forest owners to get all the information they need to make their forest climate-smart – everything from data on climate change to forest law and non-native tree species. We also put them in contact with the right people to help them help their forests get ready for climate change.

In the NETGEN project, for example, an Austria-wide network of demonstration areas was set up where one can find out much about the various tree species and origins. Here at Hochwechsel on the border between lower Austria and Styria is one of these demonstration areas. Origins of native and non-native tree species have been planted at over 1.000 meters above sea level. We want to find out which tree species are particularly suitable for high altitudes. Anyone who is interested can come here and find out more about the experiment. And there is further information about this site and all the other 30 sites on our website

Eleven recommended practical tips for forest management in times of climate change:

  1. Consider what you want your forest to look like in the future. Define your silvicultural and management goals based on natural conditions (e.g., location, future climate, etc.). Only then can you plan silvicultural measures.
  2. Promote a stable, well-structured, multi-staged mixed forest and introduce tree species suitable for the climate. If possible, a mixed forest should consist of at least four tree species – planted in groups that are min. 200-400 m2. This lowers the risk to your forest.
  3. Avoid large clear-cuts; the forest floor can easily become too hot. In addition, a number of other problems can occur, such as regeneration difficulties, erosion, and loss of humus and nutrients.
  4. Timely maintenance and thinning are imperative. This can promote vigorous trees with sufficiently long crowns, thick trunks, and well-developed root systems, thereby increasing forest stability. Shorter rotation periods should be aimed at in order to minimize the risk in uncertain climatic conditions.
  5. Avoid soil erosion and compaction by using gentle use and hauling systems (do not drive over the forest floor under any circumstances).
  6. Check the forest regularly for bark beetle infestation and remove infested trees immediately.
  7. Develop well- tiered and richly structured forest edges. These can help reduce damage from drought and storms and promote biodiversity.
  8. Ensure that seeds and seedlings are of appropriate provenance (
  9. Work closely with hunters. Excessive game populations must be reduced to reasonable levels so that browsing-sensitive tree species have a chance and diverse regeneration can be ensured.
  10. Increase biodiversity by providing a variety of tree species and diverse habitats such as dead wood, veteran trees, and encouraging a shrub and herb layer. This will make your forest more resistant to disease, pests and calamities.
  11. Find out about the relevant legal regulations and seek advice from experts.