ABSTRACT
The study examined some wood pulp properties of Pinus
caribaea(morelet) grown in Oluwa forest reserve ( a world bank assisted
pulpwood project) in Ondo State, Western Nigeria. The study determined the
extent to which the variation in wood density of Pinus caribaea (morelet) was
associated with differences between plantations, between trees and within
trees, investigate the relative suitability of the wood species based on
density and other wood properties for pulp and paper making, determine the
relationship, if any, between wood density and shrinkage variations and
determine the effects of ring width on wood density and wood type. Wood samples
were collected from different age classes and each age class was a 25 hectare
plantation. The ages were 15, 16, 17, and 18 years, established in 1989, 1990,
1991, and 1992 respectively. Three (3) well formed trees were randomly selected
from each plantation. Diameter at breast height and the 4 cardinals were marked
before the trees were felled. A total of sixty (60) discs of 50 millimetres
(mm) in thickness were collected at 5 sampling levels of 10%, 30%, 50%, 70% and
90% of merchantable length from the 4 plantations. Strips of 20mmx20mmx20mm
were obtained when each disc was sawn radially from the bark to the pith and partitioned
into inner wood (A), middle wood (B), and outer wood(C) based on the number of
annual rings counted from the pith to the bark. Data obtained were analyzed
using graphs, analyses of variance, correlation and regression. Differences in
wood density, shrinkage and ring width due to age, level and tree were highly
sinificant. Mean values for wood density were 0.52g/cm 3,0.47g/cm ,0.43g/cm3and
0.36g/cm3for 15, 16, 17, and 18 years old plantations respectively. Wood
density increased with decreasing age. Variance components from the age classes
were 30.9%, 27.6%, 25.1% and 27.5% in respective ages. Wood density variation
axially did not follow any patter in all the 4 plantations. Ring width
variation along the bole did not follow any pattern in 15 and 16 years old
plantation. In 17 and 18 years old plantation, ring with increased with
decreasing ring number with mean values of between 1.6% and 2.4%. However, a
strong correlation existed between sampled levels in all the plantations. The
pattern of volumetric shrinkage showed an increase with increasing level with
mean values that lay between 7.2% and 12.5% with a prediction of 74.5%. The
effect of wood type on the total variation in volumetric shrinkage was
significant with mean values of between 6.1% and 17.4% with a high prediction
level of 80.5%. The pattern of variation in tangential shrinkage was an
increase from the pith to the bark and mean values that lay between 2.7% and
8.2% were obtained. The highest aggregate mean value in tangential shrinkage was
obtained at 90% merchantable length with values between 2.8% and 7.2% in all
the plantations. This study did not obtain any specific pattern of variation in
radial shrinkage along the tree bole in all the 4 plantations. However, results
gave a mean average radial shrinkage that lay between 3.05 and 7.0%. The
results of this study have shown that the wood density of the species was
within the acceptable minimum (0.30g/cm 3) and maximum (0.80g/cm 3) range
recommended for pulp and paper manufacture. Pulp yield was closely related to
wood density and this research gave a minimum of 0.36g/cm3 from 18 years old
plot while the 15 years old plot gave 0.52g/cm 3.this study recommended among
other things that the plantation should be harvested without undue delay since
wood density dropped with increasing age.
UDOAKPAN, I (2021). Evaluation Of Some Wood Pulp Properties Of Pinus Caribaea (Morelet) Grown In Oluwa Forest Reserve In Ondo State, Nigeria. Mouau.afribary.org: Retrieved Nov 13, 2024, from https://repository.mouau.edu.ng/work/view/evaluation-of-some-wood-pulp-properties-of-pinus-caribaea-morelet-grown-in-oluwa-forest-reserve-in-ondo-state-nigeria-7-2
IME, UDOAKPAN. "Evaluation Of Some Wood Pulp Properties Of Pinus Caribaea (Morelet) Grown In Oluwa Forest Reserve In Ondo State, Nigeria" Mouau.afribary.org. Mouau.afribary.org, 26 Oct. 2021, https://repository.mouau.edu.ng/work/view/evaluation-of-some-wood-pulp-properties-of-pinus-caribaea-morelet-grown-in-oluwa-forest-reserve-in-ondo-state-nigeria-7-2. Accessed 13 Nov. 2024.
IME, UDOAKPAN. "Evaluation Of Some Wood Pulp Properties Of Pinus Caribaea (Morelet) Grown In Oluwa Forest Reserve In Ondo State, Nigeria". Mouau.afribary.org, Mouau.afribary.org, 26 Oct. 2021. Web. 13 Nov. 2024. < https://repository.mouau.edu.ng/work/view/evaluation-of-some-wood-pulp-properties-of-pinus-caribaea-morelet-grown-in-oluwa-forest-reserve-in-ondo-state-nigeria-7-2 >.
IME, UDOAKPAN. "Evaluation Of Some Wood Pulp Properties Of Pinus Caribaea (Morelet) Grown In Oluwa Forest Reserve In Ondo State, Nigeria" Mouau.afribary.org (2021). Accessed 13 Nov. 2024. https://repository.mouau.edu.ng/work/view/evaluation-of-some-wood-pulp-properties-of-pinus-caribaea-morelet-grown-in-oluwa-forest-reserve-in-ondo-state-nigeria-7-2