Pterocarpus santalinus Linn. f.
Nomenclature and Taxonomy
Pterocarpus santalinus is commonly known as Almug, Red sandalwood, and Saunderswood in English  while it is locally called Rakta chandan in Nepali . It belongs to family Fabaceae and is provided with synonym Lingoum santalinum (L.f.) Kuntze 
Pterocarpus santalinus is a small to medium sized deciduous tree; with extremely hard, dark purple heartwood of bitter flavour. Bark is blackish brown, deeply cleft into rectangular plates by deep vertical and horizontal cracks. Branchlets are drooping and hariless. Leaves are trifoilate, 10 - 18 cm with rachis swollen at base. Leaflets are braodly egg-shaped or orbicular, with round or slightly heart-shaped base, with round or deeply notched apex. Flowers are bisexual, stalked in auxiliary simple or sparingly branched racemes, yellow, about 2 cm long, fragrant. Fruit pods are unequally orbicular, flat about 5×4.5 cm including the wing, and gradually narrow into a short tip about 1-cm long. Seed is one or rarely 2, more or less kidney shaped, 1 - 1,5 cm long, smooth, reddish brown. 
Ecology and Distribution
Pterocarpus santalinus is distributed throughout the tropics especially in India, China, Sri Lanka, and Taiwan. It thrives well between 300 - 800 m and grows on hilly terrain and slopes with very shallow to shallow brown, sandy loam or bouldery soils of friable nature. In Nepal, its natural distribution is reported from Kaski district. 
Pterocarpus santalinus has been overexploited in the past for various purposes in cluding timber, dyeing, and medicine. However, its international trade is now monitored through a CITES Appendix II listing and plantation are being established. Also, it is enlisted in Endangered B1+2de ver 2.3 red list category & criteria by the IUCN red list of threatened species verion 2014.3. 
Pterocarpus santalinus is exploited for timber, the extraction of dye, medicine, and cosmetics.  Its wood bark is source of tannin. The hard wood is used for carpentry and for fence posts.  Its heartwood, fruits and bark are employed as medicine. 
Phytochemistry and Pharmacology
The heartwood of Pterocarpus santalinus is bitter, sweet, acrid, cooling, constipating, depurative, haemostatic, antiinflammatory, opthalmic, diaphoretic, anthelmintic, aphrodisiac, alexiteric, and tonic. So its used in cephalalgia, odontalgia, hemicrania, vomiting, diarrhoea, dysentery, skin diseases, leprosy, ulcers, haemoptysis, fever, general debility, and metal aberrations. Fruits are astringent and tonic, and are useful in chronic dusentery and urethrorrhagia.  Its heatwood is rubbed with water, honey, ghee, and oil, applied as collyrium to alleviate defects of vision. It is also used in bone fracture, spider poisoning, scorpion-sting, and hiccough. 
Diseases and Pathogens
- CAMP Workshops on Medicinal Plants, India (January 1997) (1998). Pterocarpus santalinus. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 24 April 2015.
- Baral, S. R. & Kurmi, P. P. (2006). A Compendium of Medicinal Plants in Nepal. Kathmandu, Nepal: Mass Printing Press. pp. 290
- The Plant List A working list of all plant species. (2015). Pterocarpus santalinus. Retrieved from http://www.theplantlist.org/tpl/record/ild-32307 on April 24, 2015.
- Arunkumara, K. K. I. U., Walpola, B. C., Subasinghe, S. & Yoon, M. H. (2011). Pterocarpus santalinus Linn. f. (rath handun): A Review of Its Botany, uses, Phytochemistry and Pharmacology. Journal of the Korean Society for Applied Biological Chemistry, 54(4), 495-500
- Ecocrop. (2015). Pterocarpus santalinus. Retrieved from http://ecocrop.fao.org/ecocrop/srv/en/cropView?id=9049 on April 24, 2015.