A leading expert on kava in Vanuatu says the loss of up to 80 percent of the world's richest collection of the plant is a blow to researchers.
Unidentified people attacked the kava collection at the Vanuatu Agricultural Research and Techincal Centre last December, leaving most of the plants useless to scientists.
Doctor Vincent Lebot said it will take time to replace the collection.
"In order to collect the varieties we have to travel to all these different islands to describe them, to grow them. Kava is a slow-growing plant, it takes about three or four years to mature, so it was a major setback, a major loss."
Dr Lebot said the Centre spent nearly 20 years building the collection of 240 plants from throughout Vanuatu, representing 82 different varieties of kava.