Arboretum is primarily a live collection of woody plants, often incorporating species of a particular group of plants or characteristic and rare taxa of a specific area or ecosystem, which are of conservation importance.  The Arboretum was established in the main campus of Kerala Forest Research Institute at Peechi, in an area of about five hectares. The area is covered by moist deciduous forests with 33 species of trees and 820 individual stands. By supplementing the existing stands by filling tree gaps available, the live collection was organized. In order to systematically organise the Arboretum, initially, the plot was demarcated into grids of 25 x 25 m size and the positions of  all the existing stands were marked and gaps for plantings were identified. Seeds of different arborescent species were collected from the moist deciduous forests of the State along with those of a few endemic species from the adjoining semievergreen, evergreen and dry deciduous forest types. The collected seeds were germinated in the nursery established for the purpose at  the Field Research Station of the Institute at Veluppadam in Thrissur  District, with the details generated on germination percentage of most of them. When the seedlings attained suitable size, they were planted in the Arboretum plot, in the tree gaps already identified, at a spacing of 3 to 4 metres, depending on the availability of space and known growth habit of the species being introduced. The positions of the newly planted seedlings were marked in the grid maps and both existing and newly added species were accessioned and labeled. The labels include details like up to date botanical names, common synonym(s), family names, local names, source locality from where new collections were made and date of planting, which are also repeated in the species enumeration part of the Handbook. The Handbook also gives botanical details of the species and the height growth of the seedlings in the Arboretum plot, since their planting. The Arboretum is maintained with necessary causality replacements, and weeding and watering, whenever required. The present holding of the Arboretum is 3089 accessions belonging to 170 species under 50 families and 122 genera, with more than 50 taxa endemic to southern Peninsular India. Arboretum is maintained with the details mentioned above and the grid maps with markings on the location details of each of the live collection. The Arboretum is also recognized internationally by inclusion in the Index Seminum with ID No. 1518 and is also enlisted in the National Network of Botanical Gardens in India.

Tree species like Tectona grandis, Xylia xylocarpa, Grewia tiliifolia, Cleistanthus collinus, Miliusa tomentosa, Dillenia pentagyna, Pterocarpus marsupium, Haldina cordifolia, etc.  are  sparsely  distributed  in  the  5 hectare Arboretum plot. The open areas in the plot were used for planting of additional species to organize the Arboretum. The plot is of undulating terrain with an altitudinal variation of 8-10  m and  is with sheet rock to the extend of  about 10x5 m apart from smaller rocky outcrops, here and there. The area is mostly with in the compound wall of the campus with fencing on the southern part. There are also two staff quarters with in the Arboretum plot. Endemic species in the Arboretum is listed below.