Table 1. The number of trials and genetic entries (N) used in both the model development (provenance and check-lot data) and for testing model performance (progeny data) parts of the study and their mean (minimum and maximum in parentheses) latitude (LAT), longitude (LONG), altitude (ALT) and temperature sum (TS).
  N LAT (°N) LONG (°E) ALT (m a.s.l) TS1
Provenance and
check-lot data
 
Finnish trials 289 63.9 (60.2–69.4) 27.0 (22.0–31.6) 178 (5–300) 1042 (577–1396)
Swedish trials 89 64.0 (60.1–67.8) 17.7 (12.4–23.2) 346 (5–775) 863 (618–1133)
Finnish entries 163 65.3 (60.0–69.8) 26.3 (17.8–31.3) 170 (5–415) 941 (539–1390)
Swedish entries 113 64.2 (57.6–69.8) 18.5 (12.8–28.6) 291 (5–850) 888 (528–1530)
Progeny data  
Finnish trials 19 62.4 (60.7–66.5) 26.3 (24.1–29.4) 128 (71–282) 1186 (756–1346)
Swedish trials 100 64.5 (61.0–67.6) 18.5 (12.4–23.3) 313 (25–724) 856 (618–1066)
Finnish entries 690 62.0 (60.0–66.8) 27.0 (21.6–30.9) 122 (82–283) 1220 (838–1341)
Swedish entries 3231 65.2 (61.7–68.5) 18.9 (13.0–23.8) 314 (0–754) 829 (452–1077)
1 Long term average heat sum (degree days), threshold 5 °C.
1

Fig. 1. Field trial sites a) and genetic entry origins b) used for the model development part of the study. Provenance trials and origins are indicated by black crosses and progeny trials and check-lots by black dots.

2

Fig. 2. Field trial sites a) and genetic entry origins b) used for model performance testing in the study. Progeny trials with half-sibs and their origins are indicated by black crosses and progeny trials with full-sibs and their origins (mid-parent values) by black dots.

Table 2. The average number of genetic entries per trial, trials per genetic entry, trees analyzed and mean survival, height, establishment year, age of height assessment, and age of survival assessment used in both the model development (provenance and check-lot data) and for testing model performance (progeny data) parts of the study (maximum and minimum values in parentheses where applicable). View in new window/tab.
Table 3. A summary of the variables describing geographical location, site and climatic conditions for trial sites and genetic entry origins.
Variable Time span1 Description
LAT - Latitude (degrees, WGS84)
LONG - Longitude (degrees, WGS84)
ALT - Altitude (m a.s.l.)
TS ANN Long term average temperature sum during the growing season (degree days), threshold 5 °C.
Tmean ANN, DJF, MAM, JJA, SON Mean temperature (°C)
ContInd ANN Continentality index calculated as the difference between the average July mean temperature and January mean temperature. A lower value represents a maritime climate whereas a higher value represents a continental climate.
VegPer ANN Vegetation period length. The number of days between the start and end of the vegetation period.
VegStart ANN Vegetation period start. The first day of the year in the first continuous period where the mean temperature has been at least 5 °C for four consecutive days.
VegEnd ANN Vegetation period end. The last day of the year in the last continuous period where the mean temperature has been at least 5 °C for four consecutive days.
MaxDrySpell2 ANN, AMJJ, ASO Dry spell (days). The longest continuous period in which the precipitation is <1mm/day.
precipSum2 ANN,
AMJJASO
Precipitation (mm).
1 Different time spans for the variable. ANN = Annual. DJF = December–February. MAM = March–May. JJA = June–August.    SON = September–November. AMJJ = April–July. ASO = August–October. AMJJASO = April–October.
2 The drought and precipitation indices exhibited systematic differences between the countries (Bärring et al. 2016) and could    therefore only be used for within country analyses.
Table 4. Coefficients and variance estimates with the natural logarithm of height as the dependent variable. Independent variables are the age of height assessment (ah), establishment year minus 1945 (EY-1945), temperature sum (TS) and transfer in latitude (ΔLAT).
Variable Coefficient Estimate p-value
Intercept μ –6.0063 <0.0001
ln ah α1 1.6279 <0.0001
ln (EY-1945) α2 0.156 <0.0001
ln TS α3 0.995 <0.0001
ΔLAT β1 0.02907 <0.0001
ΔLAT2 β2 –0.01714 <0.0001
TS×ΔLAT γ1 –0.00005 <0.0001
TS×ΔLAT2 γ2 0.000011 <0.0001
Variance between trials   0.06237  
Variance within trials   0.03336  
Total variance in dependent variable   2.1907  
Table 5. Coefficients and variance estimates with the logit transformed survival projected to 2.5 m height as the dependent variable. Independent variables are temperature sum (TS), transfer in latitude (ΔLAT), altitude (ALT) and a dummy variable ( δ ) where 0 represents Sweden and 1 Finland.
Variable Coefficient Estimate p-value
Intercept μ –86.3416 <0.0001
Country δ –0.9286 <0.0001
TS α1 –0.01082 0.0005
ln TS α2 14.2905 <0.0001
ΔLAT β1 0.1626 <0.0001
ΔLAT2 β2 –0.05642 <0.0001
ALT×ΔLAT γ1 0.000864 <0.0001
ALT×ΔLAT2 γ2 –0.00007 0.0011
Variance between trials   0.8134  
Variance within trials   4.0489  
Total variance in dependent variable   27.5474  
Table 6. The four representative sites chosen to illustrate the model performance.
Site LAT1 TS2 ALT3 Description
62M 62 1200 100 Milder coastal areas in central Sweden and milder areas in southern Finland.
62H 62 750 450 Harsher high-altitude sites in central Sweden.
66M 66 1000 100 Milder low-land and coastal areas in northern Sweden and Finland.
66H 66 650 350 Harsher areas with higher altitudes in northern Sweden and Finland.
1 Approximate latitude corresponding to the general site description and combination of TS and ALT.
2 Long term average heat sum (day degrees), threshold 5 °C.
3 Altitude (m a.s.l.)
3

Fig. 3. Height in meters at age 30 years as a function of latitudinal transfer from four representative sites. Two sites are at latitude 62°N, where one is considered mild (62M) and one harsh (62H), and two at latitude 66°N, where one is considered mild (66M) and one harsh (66H). For detailed descriptions of the sites see Table 6.

4

Fig. 4. Survival at 2.5 meters height for (a) Sweden and (b) Finland as a function of latitudinal transfer from four representative sites. Two sites are at latitude 62°N, where one is considered mild (62M) and one harsh (62H), and two at latitude 66°N, where one is considered mild (66M) and one harsh (66H). Note that (62H) represents a site type that does not occur in Finland and is therefore not shown in (b). For detailed descriptions of the sites see Table 6.

5

Fig. 5. The deviation, d, between the recorded value and the predicted value of (a) the logit transformed survival and (b) the ln-transformed height for the genetic entries in the progeny data. For each latitude class the mean value (black cross) and standard deviation (bars) are given.