The genus Pterocarpus belongs to the subfamily - Papilionoideae of Fabaceae in the order Leguminosae (Gupta, 1969). The genus name was given as Pterocarpus by Linnaeus in 1754. The genus Pterocarpus comprises five species viz., Pterocarpus marsupium , Roxb.; P. santalinus Linn.; P. dalbergioides, Roxb.; P. macrocarpus, Kurz and P. indicus, Wild (Troup, 1921a). The genus Pterocarpus is important to the forester because it contains some very valuable trees and is recognizable by its ovoid, wrinkled, or spherical winged one-seeded fruits. There was different information about the number of species of the genus Pterocarpus. This genus is known to include 60 - 70 species (Allen and Allen, 1981), 15

species (Hooker, 1879; Brandis, 1907) or 35 species (CD-ROM, FRI, Yezin) occurring in the tropics and subtropics of both hemispheres and that 5 species occur in India (Gamble, 1922; Troup, 1921b; Pearson and Brown, 1932 and Anonymous, 1962). Hundley and Chit (1987) listed 3 species growing in Myanmar. Within the genus, some Pterocarpus species are rosewood tree species that are highly valued for their high- quality wood and whose dark red, high - grade heartwood is of great economic value for the production of fine furniture, traditional medicine and handicrafts such as musical instruments. The growth rate is relatively slow, they have been overexploited, and in some cases the timber and medicinal value could also be driven to extinction (Waeber et al., 2019). P. marsupium Roxb. is a valuable multipurpose forest tree in India and Sri Lanka, popularly known as Bijasal because of its high-quality wood and pharmaceutically bioactive compounds, especially from the stem bark and heartwood. It is native to India, Nepal, and Sri Lanka, where it occurs in parts of the Western Ghats (Gamble, 1935 and Matthew, 1983). The kino tree (Pterocarpus marsupium) is a medium to large deciduous tree that occurs at altitudes of 200 to 500 m. The species' current population is declining in the wild, which is listed as Near Threatened in the IUCN Red Book. It is an excellent timber tree species and ranks alongside teak and rosewood in Peninsular India. It is exploited for its wood and medicinal bark (Ramya et al., 2008). For the latter, the plant may be felled or its bark removed (Abirami et al., 2012). Its wood is often compared to teak and has received less attention for extensive cultivation and native stands are rapidly disappearing despite being little known to forester’s worldwide and little trialed in plantations. P. marsupium, a tree with timber value, is less well known to farmers. To protect and conserve the Indian kino tree, it should be planted under various afforestation and reforestation programmes (Sukhadiya et al., 2019). P. marsupium has long been used in India to treat diabetes and the gum of the tree contains the astringent "kino". P. marsupium which occurs in India, are commercially important timber tree which are in demand in the international market. Since, this species falls into the "near threatened" category, it should be conserved and used sustainably to prevent further depletion.

The survey was conducted during 2021-2022 for bark characteristics variation study of P. marsupium in two states, namely Gujarat (GJ) and Maharashtra (MH). The five trees per replication per treatment which had more than 25.00 cm diameter at breast height were randomly selected from purposively selected locations known for its abundantly presence or cultivation; the different five sites of each state were used as locations depending on the available resources. The locations of P. marsupium from Gujarat were named as GJ-PM-1, GJ-PM-2, GJ-PM-3, GJ-PM-4 and GJ-PM-5, whereas in Maharashtra it was named as MH-PM-1, MH-PM-2, MH-PM-3, MS-PM-4

and MH-PM-5 (Table - 1). Amultistage random sampling method was used to select the trees and the corresponding data were collected in the field. Bark thickness and other characteristics of randomly selected trees were measured at field. Bark thickness of randomly selected trees in different locations was measured horizontally at the four points (evenly spaced or where the caliper arms contact the bole) in the tree by using bark gauge at breast height and expressed in centimeters (cm). Bark is a type of tissue that grows over a tree's wood. It has both an inner and outer layer. The inner layer is living tissue, and the outer layer is dead tissue. Bark types can be identified as smooth, rough, elongated plate like scales, rectangular/ square plate like scales, longitudinally fissured, puffy ridges and deep furrows, shallow ridges and shallow furrows. Bark types of randomly selected trees from different locations was categorized as per above category by ocular method. Bark colour of randomly selected trees from different locations was categorized as brown, whitish-brown, yellowish- brown, reddish-brown, blackish-brown and black by colour chart. The observations were recorded and processed for statistical analysis by using complete randomized block design and two sample t-test. The recorded data were presented in table and interference was drawn.

The analysis of bark thickness of P. marsupium in various locations revealed significant variability among different locations of Gujarat and Maharashtra while it showed non-significant variation between two locations. Bark thickness ranged from 1.40 to 2.90 cm, with notable differences between locations in Gujarat (GJ) and Maharashtra (MH). GJ-PM-4 exhibited the maximum bark thickness, while MH-PM-4 had the minimum. Notably, some locations displayed unique features, such as smooth bark in GJ-PM-4 and MH- PM-1, while MH-PM-5 exhibited a distinctive rough bark with exfoliation but no exudates. The bark colour mostly varied from light brown to blackish brown and yellowish brown. These variations underscore the importance of considering the geographical origin of

P. marsupium when assessing its bark characteristics.

This variability in bark attributes, including roughness, texture, fissures, colour and flake patterns, provides valuable diagnostic characteristics for the identification of P. marsupium. This investigation and further emphasize the significance of bark attributes as a key factor in species identification.

Acknowledgement: We would like to thanks to authority of Navsari Agricultural University, Navsari (GJ) for giving opportunity and avail facilities to conduct research work and thankful to the State Forest Department of Maharashtra and Gujarat and the Bijasal tree growers. Also, thanks to my research guide and other SAC members for their guidance to compile the data and its analysis