Each Forest Management Unit (FMU) of the company has a detailed record of the areas established with mature, young and newly planted crops of rubber, tea and coconut. In addition it also maintains records of production for each crop and the productivity of individual division and estate by monthly. These data are maintained in the offices of the estates and reported to the head office in Colombo. Monitoring the changes of natural forest area is achieved through permanent sample plots (PSPs) marked in the natural forest area.

In addition, Permanent Sample Plots have been marked in randomly selected fields in order to monitor the growth of the Latex Timber / Timber / Fuel wood plantations. Girth at Breast Height (GBH) and Height of the trees are measured annually so that growth measurements, Growing Stock, Mean Annual Increment (MAI), and Current Annual Increment (CAI) are worked out. Outcome of the above will be utilized to get the maximum benefit from our forest plantations.

The girth of all the trees are measured annually at a level of 48’ from the ground level till the tree is ready for tapping in immature rubber plantations. These information is recorded for assessing the growth of the trees. A 10 cm girth increment of the immature rubber trees per year is expected, if a tree shows a lesser growth increment a special procedure is followed to get the girth increment to the required level.