vn] HEIGHT OF BORNEAN TREES 



" para-para," is built round the trunk a few feet from the ground, 

 so that the woodcutters can work on the cylindrical portions of it. 



I took careful measurements of some of the ordinary trees of 

 medium size felled around my house. A species of Hopea was 121 ft . 

 high ; a tree of an undetermined species measured in the cylindrical 

 portion of the trunk, bare of branches, 79 ft., and " over all " 145 

 ft. The bare trunk of a Sliorea was 65 ft. in length, the entire 

 growth being 138 ft. Such measurements only give an idea of 

 the medium height of the forest trees halfway up Mattang. On 

 the plain below, many trees I felled reached or surpassed 160 ft. 

 in height, and in favourable conditions in the mountain gorges, 

 and where the soil is rich, some trees in Borneo attain very much 

 larger dimensions. 



As regards girth, one of the largest — and it was very common 

 near " Vallombrosa " — was the bilian (Eusideroxylon Zwageri). I 

 measured a trunk of one of these trees which was 33 ft. in cir- 

 cumference at a height of 4 ft. from the ground. The bilian pro- 

 duces what is, perhaps, the most valuable timber in Borneo. No 

 insects attack it, not even the white ant, and it does not rot in 

 water nor deteriorate by exposure. It is asserted that even under 

 the worst conditions it can last over 200 years, and it is, therefore, 

 much used in the construction of houses. 



In my earlier journeys to Mattang I had had ample opportunities 

 of noting the immense variety and richness of its flora, but my 

 expectations were greatly surpassed by the reality. Every morning 

 I used to go into the forest with my men, and I always returned 

 with loads of specimens. I used carefully to search the ground for 

 indications of blossoming trees of which it was worth securing 

 specimens, for most have inconspicuous flowers not easily seen 

 from below. Thus, only a careful examination of the soil beneath 

 can lead, by the detection of fallen flowers, to the knowledge of the 

 right time of collecting. But in many cases it was not easy to trace 

 the tree which produced the flowers found on the ground ; 

 and more than once I was obliged to cut down two, three, and even 

 four trees before getting the right one, and this although I had 

 acquired some experience in distinguishing the principal families of 

 trees by the bark, and especially by the nature of the sap, i.e., if 

 milky, watery, resinous, etc. 



The flowering of trees in Sarawak is nearly continuous, or, rather, 

 trees are found in blossom at all seasons of the year. But when 

 seasonal abnormalities occur, which is by no means rare, the flower- 

 ing also varies somewhat, and may repeat itself more than once 

 during the year. Many of the Bornean species, however, come into 

 blossom at regular periods, and often all the species of a genus 

 develop their flowers at the same time. Thus, there was a period 

 for the genus Diospyros, then came the turn of the Sapotaccce, and 

 then of the Dipterocarpece. 



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