Research was conducted in twenty-seven selected villages located in Jorhat and Golaghat districts of upper Assam, northeast India, for population estimation, quantitative ecological analysis, and evaluation of Aquilaria malaccensis (Thymelaeaceae). Vegetation sampling was done by quadrat method and A. malaccensis is the most dominant tree species in all twenty-seven different study sites of upper Assam contributing 10–54% of the total tree density with a mean of . Density of the species varied from 6,236 individuals ha？1 to 429 individuals ha？1 with a mean of 1,609 individuals , whereas frequency of occurrence is very high ranging from 93% to 100% with a mean of in different study sites. Distribution of A. malaccensis is found contagious in all twenty-six study sites on the basis of abundance to frequency ratio except in KBG, Golaghat, where its distribution is random with 0.04 abundance to frequency ratio. The widespread cultivation of A. malaccensis in upper Assam, northeast India, offers a potential ex situ reservoir for the future conservation and management of this threatened tree. 1. Introduction Aquilaria malaccensis (Thymelaeaceae), locally known as “Sanchi” or “Agaru” in Assamese, is an evergreen tropical forest tree highly priced for its resin or agarwood. The species is valued in many cultures for centuries because of its distinctive fragrance and used extensively in incense, perfume, and traditional medicine. Natural populations of Agaru are distributed in south and southeast Asia and in India; it occurs mostly in foothills of northeastern region (Assam, Arunachal Pradesh, Nagaland, Meghalaya, Mizoram, Manipur, and Tripura) as well as West Bengal [1]. However, large scale harvesting of the species from natural population caused rapid depletion in the wild and is listed in Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) in 1994 [2]. The species is “vulnerable” globally according to the current IUCN red list [3]. On the other hand, Agaru is extensively cultivated in homegardens of upper Assam and contributes significantly up to 20% of the total annual income of the family with a mean of to the economy of the local people [4]. A good population stock of Agaru with highest density and frequency in homegardens of upper Assam was also reported by Saikia et al. [5]. Two distinct morphs of Agaru (Bhola Sanchi and Jati Sanchi) are cultivated in homegardens of upper Assam with different life form characteristics [6]. Bhola Sanchi is fast growing and less agarwood yielding than the other
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