Finnish pedunculate oak measured for growth and survival

Text: Juho Hautsalo,  Natural Resources Institute Finland (Luke) Finnish pedunculate oak (Quercus robur) populations are very small, isolated and when compared to Central European oak populations they have higher genetic diversification rate and lower diversity. This is typical for populations that are close to the border of the natural distribution of the species.

Growth and survival measured

Descendants from six different Finnish oak forests were evaluated against their growth and survival in five trial locations across Southern and Central Finland. The trees were measured at the age of 13 years. Height-sum equation was applied to combine height and survival and Wright’s ecovalence equation was used to estimate the population and family level stability among different environments. Seedlings from same mother tree were considered as a Family.

Significant differences in robustness among origins and families

Finnish pedunculate oak populations differed statistically in their height and survival. Certain populations were clearly better growing and surviving than the others. Moreover the height-sum and the stability of the height-sum across the trial locations had significant differences among origins and among families. Based on these results a population that had clearly weaker adaptation to changing climate was found. On the other hand some families with very good height-sum and stability, and thus stronger adaptation abilities, were pointed out. Suitable microclimate and good origin seem to make it possible for oak forests to succeed above their natural distribution limit.

Read more:

Hautsalo J., Mathieu P., Elshibli S., Vakkari P., Raisio J., Pulkkinen P. (2015). Variation in height and survival among northern populations of pedunculate oak (Quercus robur L.): results of a 13-year field study. Silva Fennica vol. 49 no. 2 article id 1274.

http://dx.doi.org/10.14214/sf.1274