TITLE:
Analysis on the Growth Rhythm and Cold Tolerance of Five-Year Old Eucalyptus benthamii Plantation for Bioenergy
AUTHORS:
Aihua Yu, Tom Gallagher
KEYWORDS:
Eucalyptus benthamii, Growth Parameters, Bioenergy, Cold Tolerance
JOURNAL NAME:
Open Journal of Forestry,
Vol.5 No.6,
July
31,
2015
ABSTRACT: A
research plot of Eucalyptus benthamii was planted to evaluate this species’ ability to supply the emerging bioenergy
markets that are developing in the southern U.S. The plot was planted in two
different densities to investigate the growth parameters and the cold
tolerance. The stand was measured annually through five growing seasons. The
results indicated that the growth difference among the young E. benthamii was noticeable. For
example, the maximum and minimum value of five-year old trees at diameter
breast height (DBH) was 27.9 centimeters and 1.27 centimeters; and the maximum
and minimum value of tree height was 22.86 meters and 2.44 meters,
respectively. The yearly change in DBH and height of E. benthamii had significant differences. The average annual
survival rates of E. benthamii had
differences under the two planting densities (1650 trees ha-1 and
1237 trees ha-1). The densities also had effects on the height and
DBH growth of E. benthamii. The
average DBH and height of 1650 trees ha-1 plantation were 11.18
centimeters and 15.03 meters, and the average DBH and height of 1237 trees ha-1 plantation were 13.46 centimeters and 16.28 meters. The volume per hectare of
1650 trees ha-1 and 1237 trees ha-1 plantation were
111.45 cubic meters and 101.15 cubic meters, respectively. Average diameter
growth was almost 2.54 centimeters per year and average height growth was over
3 meters. E. benthamii plantations were
considered tolerant to -7.4 degrees Celsius and a cold spell during early 2014
(-11.3 degrees Celsius for two consecutive nights) killed the plantation. The
growth of E. benthamii also varied
depending on surrounding conditions. The difference in growth of row seven
versus row one was a good example. The reason probably was that row seven was
adjacent to a loblolly pine plantation and row one was next to an open field.