Bridging the Gap: linking timber trade with infrastructural ...

Table 22
Log size of main timber species processed by PIC Ltd., 2001
Scientific Name
Total volume
(m 3 )
Average length
(m)
Average girth
(m)
Average volume
(m 3 )
Hymenaea verrucosa 1 538.5 3.3 2.0 1.1
Julbernardia globiflora 401.3 3.6 2.1 1.3
Brachystegia spp. 184.7 3.1 1.9 0.9
Trichilia emetica 131.7 3.6 1.2 0.4
Afzelia quanzensis 69.0 2.3 1.7 0.6
Erythrophleum africanum 53.4 2.9 1.5 0.6
Amblyogonocarpus obtusangulus 9.1 3.1 1.7 0.7
Apodytes dimidiata 5.1 3.8 1.7 0.8
Rhus spp. 4.9 3.5 2.1 1.2
Newtonia spp. 2.9 3.6 1.8 1.0
Lannea schweinfurthii 2.8 3.8 2.1 1.4
Sclerocarya birrea 2.6 2.8 1.7 0.7
Pterocarpus angolensis 1.1 2.9 1.6 0.6
Millettia stuhlmannii 0.5 2.9 1.1 0.3
Source: PIC Ltd. sawmill, 2001.
There is significant variation in log size between different timber species. The average length, girth and
volume were 3.3 m (ranging 2.3 – 3.8 m), 1.8 m (ranging 1.1 – 2.1 m) and 1 m 3 (ranging 0.3 – 1.4 m 3 ),
respectively. The largest girth sizes were for Lannea schweinfurthii, Julbernardia globiflora, Rhus spp.
and Hymenaea verrucosa, whilst smallest sizes were for Millettia stuhlmannii and Trichilia emetica. As
expected, a clear relationship exists between average log volume and average girth measurements (Figure
19):
volume = (0.93 x girth) – 0.82
Figure 19
Relationship between average volume and average girth of timber species whose processed
volumes by PIC Ltd. exceeded 10 m 3 during 2001
Volume (m3)
1.4
1.2
1.0
0.8
0.6
0.4
0.2
y = 0.9612x - 0.8411
1.1 1.3 1.5 1.7 1.9 2.1
Source: PIC Ltd. sawmill, 2001.
Girth (m)
52