An arboretum, in a general sense is a collection composed exclusively of living trees. Arboreta are usually developed by planting trees, but the NIFS Sam Popham's arboretum has been developed using a method known as Assisted Natural Regeneration (ANR).

ANR is one of the important methods used in restoration ecology. NIFS Sam Popham's Arboretum (NIFS-SPA) is a benchmark site in Sri Lanka for ANR.

The NIFS-Popham Arboretum was founded by Mr. F H (Sam) Popham in 1963. He bought a seven and half acre-land of scrub jungle to initiate the arboretum. This arboretum was gifted to the Institute of Fundamental Studies (IFS), Kandy In 1989. The arboretum now has 34.5 acres with the addition of 27 acres in 1989, through the initiative of Prof Cyril Ponnamperuma, a former IFS Director.