Worked as Scientist in the Kerala Forest Research Institute for 36 years. Was the Programme Co-ordinator of the Forest Ecology and Biodiversity Conservation Programme Division. Superannuated from the service on 31.08.2012. The thrust areas of research are Systematic Botany, Ecology and Non-wood Forest Products. Carried out studies on the sustainable extraction of NWFPs, Quantitative Inventory of Non-wood Forest Produces, Mass multiplication and agro-technology of medicinal plants, Phytochemical screening and Biological property, Assessing Raw drugs consumption and requirements of Ayurvedic medicine industry and Ethnobotany of Tribes in the forests. Extensively worked on the Forest Flora, particularly Wildlife Sanctuaries and Forest Trees of Kerala. Developed a digital flora of Kerala consisting of 5094 species in 2011 and Tree Identification Program for the Trees of Kerala (650 tree species) based on field and vegetative characters in 2007 and revised version in 2016. Published 46 Research Reports; 7 Books; 115 Scientific papers and 12 popular articles. Described 26 new species including 7 trees.

PhD in Botany from Calicut University for the Thesis Forest Flora of Thrissur District under the guidance of Dr. V.V. Sivarajan in 1993. International Diploma from Royal Botanical Garden, Kew, England in 1995. Recipient of Dr.VVSivarajan Gold Medal from the Indian Association of Angiosperm Taxonomists in 2004. Dr.B.P. PAL Fellowship of Ministry of Environment & Forest, Govt. of India in 2010, for the outstanding contributions in the field of biodiversity. Emeritus Scientist of Kerala State Council for Science, Technology and Environment, Government of Kerala from 2014 -2017.