Endogeneous or endogen timber

This kind of trees increase both longitudinally and diametrically.Its diameter increase by the addition of new fibre with the old. Endogens are mostly plants like paddy, sugarcane, jute etc.

Exogeneous or exogen timber

This kind of trees increase diametrically by annual formation of layer new wood between old wood and bark of the wood which consists all the living portion of the tree.

Types of Timber

Timber is of mainly two types.
1.Exogeneous or exogen
2.Endogeneous or endogen

Estimation of Wastage if Timber

In conversion of timber there is a great wastage.When a log is sawn only 50 to 65 percent can be useful other is waste.Following are the approximate estimation of wastage

Side slabs and trimmings--18%
Saw dust--12%
Bark--5%
Loss of moisture--5%