Besides Bindang, Sempilor and Podo, all our known commercial timbers are hardwoods. The first fact now is to establish whether the specimen is Heavy, Medium or Light Hardwood timber. If we have established that our specimen is Heavy Hardwood, this narrows our possible to a smaller group. Then we see whether it is a resin group or parenchyma group.
The size and arrangement of pores or vessels can often be a helpful guide. Generally speaking, pores are crowded or abundant in timbers with small pores and sparsely distributed in timbers with large pores. In some timbers the pores are solitary or almost exclusively solitary. In others the pores patterns are dominated by Radial Chains or Multiples of three or more and in some species the pores are arranged in Oblique formation.
If we study the rays on the transverse section, we will notice how wide they are. They may be fine medium width or so broad as to be visible to the naked eyes. Occasionally, what appears at low magnification to be a wide ray, will, on clearer examination proves to be a number of rays closely aggregated known as Aggregated Rays.
With the hand lens, we can easily detect the presence of extraneous material such as gums, resin, white deposit, tyloses, etc. (The Dipterocarpus and Shores species show intercellular resin and gum ducts). Tyloses are present in a large number of species. Latex tubes(traces) are regular feature of Jelutong and can be clearly seen with the naked eyes.
Perhaps the most important and helpful of all features of hardwoods is parenchyma or storage tissues. There are two types, namely Paratracheal and Apotracheal.
