54 



Dipterocarps of sufficient age to determine their growth here, and 

 even in the case of Sal {Shorea robusta) cultivated in Assam, there 

 seems to be some doubt as to the actual rate of growth of the tim- 

 ber. It appears however, that in this tree a girth of 54 inches 

 represents a growth of 65 years, and 72 inches represents 95 years 

 (Gamble's Manual of Indian Timbers). Judging by the growth of 

 young Shorea leprosula this appears to be about the growth of our 

 own species. 



Nearly all of the Dipterocarps produce a timber of some value, but 

 they vary a good deal in importance. The timbers known as Serayah 

 and Meranti are rather soft red timbers much used for planking 

 and furniture. They all belong to the genus Shorea, of which there 

 are a number of species. The Serayahs have different names 

 partly given to designate special forms of timber and partly refer- 

 ring to distinct trees, but the names are often irregularly used. 

 Thus Serayah Batu is a harder and heavier wood than the other 

 kinds. The name properly appears to belong to Shorea leprosula, 

 but is in trade applied to many apparently distinct woods of a 

 rather better quality than what is known as ordinary Serayah. 

 Meranti is equally irregularly used, and in trade at least appears 

 to be absolutely synonymous with the name Serayah. Chingal 

 (not to be confounded with Chengai) is also Serayah. 



The trees appear to be liable to the attacks of a fungus which 

 destroys the heart, and renders it worthless. This generally begins 

 from a wound on the trunk and the mycelium entering at this 

 point grows upwards and downwards. The remains of the centre 

 eventually is found to be in the form of a honeycomb like 

 structure. 



Dipterocarpus. 



A genus of about sixty species occurring all over the Malay 

 region, of which there are about thirteen here. They all consist of 

 trees usually of very great size, with moderate to large leaves, 

 fairly large flowers, usually red or cream colored, and sw r eetly 

 scented. The fruit is globose or oblong, either quite smooth or 

 furnished with five ridges or wings, and bearing on the top two 

 very large oblong linear wings. The fruit which is usually red-is 

 much larger than that of the Serayas, (Shorea) and is distinguished 

 by the wings arising from the top of the fruit and not being partly 

 free from it. The wings of the fruit in all these plants are the 

 developed sepals, and in Shorea these are so far free from the fruit 

 itself that the top of the fruit can be seen projecting between them, 

 whereas in Dipterocarpus the wings appear to stand on the top 

 of the fruit, the tube of the calyx being adnate to it. 



Some of the Dipter^carpi here flower almost annually, others 

 only once in five or six years ; but they are more often to be met 

 with in flower than the Shoreas. 



As a rule, the timber of the Dipterocarpi is not considered of 

 much value, being inferior in most cases to Shorea timber. They 

 produce however the wood-oils and have always had an economic 

 value for this. 



