4 



Eurya acuminata, Morinda tinctoria, Pithecolobiums, Glochidian 

 and in some places Tembusu (Fagroea fragrans.) 



Ground under Belukar often remains so for many years even 

 if not burnt, but in time second class timbers, Oaks, Shoreas, 

 Artocarpi and other trees appear and eventually after the lapse 

 of many years may again become good forest. That is to say 

 seed of the better timbers may drift into the Belukar, and as they 

 grow up may gradually replace the inferior kinds. This, however, 

 depends much on the proximity of good forest with adult fruiting 

 trees, and even in such a case ground often remains under Belukar 

 apparently for an indefinite period. 



Wood-structure. — When trees have attained a certain age, there 

 is, as a rule, a more or less distinct separation in the timber into 

 heartwood or sapwood, and the proportion of the two form an im- 

 portant factor in deciding the value of the tree as timber. The 

 outer sapwood is usually white and soft and valueless. The. heart- 

 wood in which the wood cells have increased much in thickness is 

 often distinctly coloured and is the most valuable part of the tim- 

 ber. It may be coloured red or brown, or even black as in the 

 case of Ebony. Trees vary very much in the thickness of the sap- 

 wood. In some, such as Cassia siamea, the proportion of heart- 

 wood is very small, while in Damarlaut the whole tree appears to 

 consist of heartwood. As a rule, the proportion is the same ap- 

 proximately for the same kind of tree, but certain trees are most 

 irregular in this. I have seen very large trees of Albizzia Moluc- 

 cana felled in which the wood was soft and white all through, while 

 trees of the same size or even smaller, contained a considerable 

 proportion of brown heartwood. The sapwood is usually very soon 

 destroyed by termites and fungi, and natives in felling such trees 

 as Rengas [Melannorhcea) often leave the trunk in the forest till 

 the termites have destroyed the sapwood entirely, when they re- 

 move the heartwood which is not touched by these insects. The 

 proportion of sapwood to heartwood depends most on rapidity of 

 growth. Many quick-growing short-lived trees make nothing that 

 can be called heartwood, the wood all through being soft and white, 

 such are the common wild figs. I hese soft woods are known to 

 the Malays as Lampong. They are not necessarily useless; being 

 light they are used for floating heavier timbers down stream and 

 some are used for making boxes, models and clogs, and such like 

 articles. 



Rings. — As has been remarked the rings of our timbers cannot 

 at least always be relied on as giving the age of a tree. I have 

 been unable, however, to make many examinations as to this, be- 

 cause of the difficulty of finding out the age of any given tree 

 accurately as there have been but few records kept of tree planting. 

 A specimen of the Krian {Eugenia grandis) of which the age 16 

 years \va> known gave a corresponding series of annual rings. 



roves — are really the mouths of the vessels in the wood seen in 

 transverse sections. They vary very much in size in various 

 timbers, in some they are very minute while in others they are 

 large and conspicuous. This is especially the case in the woody 



