Growth dynamics of Scots pine geographical provenances in Latvia.

摘要

Results from geographical provenance trials (totally 40 foreign provenances from Poland, Eastern Germany, Russia, Belarus, and Ukraine) in three test locations in Latvia have been evaluated. For analysis only superior trees (10% of the highest trees in each provenance) have been chosen. Results indicate that credible evaluation (observed trend does not change with increasing tree age) of survival for provenance groups from different regions can be done at the age of 6 years, for growth traits - at 15 years, but growth performance of individual provenances vary considerably up to the age of 28 years. Provenance influence on height and diameter growth is highest, exceeding regional influence even three times for height and twice for diameter. Results of geographical Scots pine trial are site-dependent. Provenances from the same region tested in 3 different test locations in Latvia at the same age demonstrate differences in survival up to 16% and in yield more than double. Average growth and survival of Eastern German and Polish Scots pine provenances decrease when comparing the areas with mild, maritime climate (Liepaja and to a lesser extent Zvirgzde) and the areas with harsher, more continental climate (Kalsnava). The decrease is sharper for Eastern German provenances. In Kalsnava, the performance of Polish and East German provenances differs considerably from the general trend, described in the literature. We suggested that the Kalsnava area could be taken as an indicator for a borderline for growth patterns of transferred Scots pine provenances..