For the collection of live specimens and to explore new ones, extensive field trips were conducted throughout India especially in South India, Northeast India, Himalayas and Andaman and Nicobar Islands from 1990 onwards. More than 100 expeditions have been made in the dense forests of those areas by the team. More than 200 species under 20 genera and about 2000 accessions were collected and maintained in the Calicut University Botanical Garden. Herbaria were also prepared from all these collections.