In 1991 a silver fir provenance trial with experimental plots at different altitudes (from 650 to 1100 m a.s.l.) has been established in the Swiss Jura mountains near Solothurn. The experiment includes four provenances from southern Italy (three from Calabria and one from Molise) and two from Switzerland.
The main questions are related to the influence of planting site altitude on growth, flushing and vitality of the various provenances, as well as to the differences between and within the two groups of provenances. We measured plant heigth in 1991 (shortly after planting) and date of flushing in 1994 and 1995. Mortality was recorded annualy.
Differences in height proved significant between proveniences, as well as differences in mortality and mean date of flushing. The Swiss provenance "Ochsenboden" survived significantly better than all other provenances (the mortality rate was only 4.4%, compared with a average of 22.8%). We suppose that "Ochsenboden", which is known as a ecotype with a high drought resistance, was less stressed by the lang periods without rainfall during the summer 1991 (the year of planting) than the other provenances.