Table 1 Characterization of the environmental variables for spruce and beech plots used for model fitting

Summer/annual temperature

Mean annual temperature (°C)

T

7.4

1.1

8.4

1.2

Mean temperature warmest quarter (°C)

T_wq

15.4

1.2

16.1

1.1

Mean temperature May to Sept. (°C)

T_5to9

14.1

1.2

14.7

1.1

Max. temperature warmest month (°C)

Tmax_wm

21.3

1.5

22.1

1.4

Mean July temperature (°C)

T7

16.2

1.2

16.8

1.1

Winter temperature

Mean January temperature (°C)

T1

−1.5

1.4

−0.2

1.6

Min. temperature coldest month (°C)

Tmin_cm

−4.2

1.5

−2.9

1.5

Precipitation

Annual precipitation sum (mm)

P

882

176

831

147

Precipitation sum warmest quarter (mm)

P_wq

270

54

238

42

Precipitation sum May to Sept. (mm)

P_5to9

420

80

382

63

Continentality

Continentality index (Conrad 1946)

ci

36.5

3.8

35.7

3.6

Tmax_wm–Tmin_cm (°C)

Txn_range

25.6

1.7

25

1.6

T_wq–T1 (°C)

T_range

17

1.2

16.3

1.3

Elevation

Elevation (m)

Elevation

564

278

472

315