The first ever research publication to compere the Agarwood production ability and Agarwood quality of Gyrinops walla (Walla patta) was done by Dr. Upul Subasinghe and his colleague Mr. Dhanushka Hettiarachchi in the Journal of Tropical Forestry and Environment in October 2011. The full article is available in the following link.
The abstract is given below
Agarwood is an expensive resinous product extracted from some members of Aquilaria and Gyrinops species of the family Thymalaeaceae. Agarwood essential oil is a highly valued perfumery product in modern cosmetics and traditional Attar. Agarwood extraction from the above species and product manufacturing are done in India and Southeast Asian countries. However, over harvesting, low natural regeneration, and legal restrictions at present, have limited the supply of this product. Gyrinops walla is recorded in the wet zone of Sri Lanka, and it had been very rarely recorded in extreme Southwest India. However, recent reports of the abundance of G. walla in India are hard to find. Studies were not conducted in the past for G. walla on its ability of agarwood resin production and the quality of that resin. This study is the first to identify the agarwood resin formation and the quality of G. walla which can be used as a substitute for that of Aquilaria and other species of Gyrinops. Resinous tissues were extracted from six G. walla trees for the present study from two different areas, i.e., Labugama and Yagirala of the wet zone of Sri Lanka. The resins were solvent extracted in the laboratory and the resin quality was tested using gas chromatography analysis. The results indicated an extreme similarity of the compounds of G. walla resin with that of commercially available agarwood resins. However, further studies should be conducted to identify G. walla distribution and formation of agarwood.