LOW ROOT TEMPERATURES AND GROWTH OF EUCALYPTS 
71 
Mean Height Increment (mm) Percentage Reduction 
Soil Temperature in Height Growth with 
Species 5°C 10°C fall in Soil Temperature 
E. nitens CR 
299 
440 
32 
E. nitens CT 
277 
403 
31 
E. nitens EE 
364 
500 
27 
E. nitens ET 
395 
481 
18 
E. regnans 
436 
630 
31 
E. delegatensis 
160 
406 
61 
E. fastigata 
204 
546 
63 
Least Significant Difference 
67 
66 
Table 5. Comparison of mean shoot height increment (mm) during the experimental period at two soil 
temperatures. 
Shoot(g)/Root(g) 
Shoot (mm)/Root (m) 
Species 
Soil Temperature 
Soil Temperature 
5°C 
10°C 
Difference 
5°C 
10°C 
Difference 
E. nitens CR 
4.5 
4.0 
0.5 
2.8 
2.5 
0.3 
E. nitens CT 
4.9 
4.6 
0.3 
5.2 
4.1 
1.1 
E. nitens EE 
4.5 
4.7 
-0.2 
5.2 
4.7 
0.5 
E. nitens ET 
4.2 
3.9 
0.3 
5.1 
4.1 
1.0 
E. regnans 
5.2 
4.6 
0.6 
6.9 
4.9 
2.0 
E. delegatensis 
3.8 
4.2 
-0.4 
2.5 
3.9 
-1.4 
E. fastigata 
3.6 
4.1 
-0.5 
6.8 
7.2 
-0.4 
Table 6. Ratio of mean shoot to root dry weight growth and increment in length, and their differences at the two 
soil temperatures. 
temperature. Comparatively low and high root 
lengths were responsible for the high and low 
length ratios for E. fastigata and the Royston 
provenance of the West Gippsland (CR) form of 
E, nitens respectively. 
For those variables where there was no signifi¬ 
cant interaction between species and tempera¬ 
ture, the data from the different temperatures 
were combined to determine the significance of 
difference between species (Table 7). E. nitens 
overall grew significantly better (p < 0.05) than 
E. delegatensis for all variables, and the growth 
of E. delegatensis was significantly greater than 
E. fastigata for all variables (p < 0.001). The 
West Gippsland form of E. nitens from Royston 
(CR) grew significantly better than E. regnans 
and the other provenanaces of E. nitens for all 
variables. E . regnans was significantly better 
than E. delegatensis for all variables except root 
length and basal stem diameter. 
f Basal Stem Total Root Shoot Dry Weight Root Dry Weight Total Dry Weight 
Variable Diameter (mm) Length (mm) (g) (g) (g) 
^ em PF 5° 10° Mean 5° 10° Mean 5° 10° Mean 5° 10° Mean 5° 10° Mean 
E. nitens CR 
0.54 
0.60 
0.57 
108 
173 
141 
5.97 
8.77 
7.37 
1.33 
2.20 
1.77 
7.31 
10.96 
9.14 
E. nitens CT 
0.43 
0.54 
0.48 
53 
99 
76 
3.40 
5.89 
4.65 
0.70 
1.27 
0.99 
4.10 
7.16 
5.63 
E. nitens EE 
0.46 
0.55 
0.51 
70 
106 
88 
4.73 
6.97 
5.85 
1.05 
1.48 
1.27 
5.79 
8.45 
7.12 
E nitens ET 
0.51 
0.57 
0.54 
77 
117 
98 
5.09 
7.31 
6.20 
1.20 
1.87 
1.54 
6.29 
9.19 
7.74 
E. regnans 
0.44 
0.52 
0.48 
63 
129 
84 
4.57 
7.63 
6.15 
0.87 
1.66 
1.28 
5.44 
9.30 
7.44 
E. delegatensis 
0.38 
0.51 
0.45 
64 
103 
84 
2.98 
5.64 
4.31 
0.79 
1.33 
1.06 
3.77 
6.97 
5.37 
E. fastigata 
0.27 
0.40 
0.33 
30 
76 
53 
1.46 
3.53 
2.46 
0.41 
0.87 
0.63 
1.88 
4.40 
3.10 
Least Significant Difference 
0.04 
17 
0.80 
0.21 
0.98 
Table 7. Mean growth at each soil temperature for variables in which the species x temperature interaction was 
not significant, and combined temperature means for each species. 
