dc.description.abstract |
This study examined the possible causes of splitting
in Eucalyptus and how it can be reduced. Log samples were
obtained from plantation at Kandapola in the Nuwara Eliya
District. These samples were taken from even-age (35 year
old) trees of Eucalyptus microcorys and Eucalyptus grandis.
Patterns of splitting and splitting intensity were
measured according to the time period. Splitting in
Eucalyptus grandis was more severe than Eucalyptus
microcorys. The pattern of splitting between these two
species also varied. Splitting varied according to the
bole height in the trees and the diameter of the bole. It
was observed that the larger diameter logs were subjected
to more splitting. Splitting intensity was higher in the
mid bole height than the base and the top height of
Eucalyptus grandis trees.
The density showed an increasing trend from pith
outward and also it varied between the species. Splitting
started from the pith and extended towards the bark. Minor
splits were started from bark and extended toward the pith
during the second stage of splitting. In Eucalyptus
grandis it started immediately after felling. Splitting
time increased with increasing Equilibrium Moisture Content
(EMC) . No relationship was found between heart wood
percentage and splitting. It was found that splitting can
be reduced by reducing the stress from pith outward by
fixing ganinails at the cut surface of the logs. Also
splitting can be reduced by applying vaslin on the cutting
surfaces.
Although vaslin and gangnail treatments reduce
splitting, it was found difficult to stop splitting
completely by these treatments. Other methods are also
discussed in controlling splitting: fixing iron ring around
the log, debarking three months before felling, using
proper logging, sawing and seasoning techniques. |
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