Kava vs Kawakawa and the Maori memories of kava

Many people wonder whether there is any connection between the Kawakawa plant  (Piper excelsum) and Kava (Piper methysticum). The two plants do not only have similar names, but also look similar. Is this just a coincidence or are the two plants related and their similar names tell us something about the Maori knowledge about kava? 

Dr Vincent Lebot, the author of "Kava: The Pacific Elixir: The Definitive Guide to Its Ethnobotany, History, and Chemistry" (a truly excellent book) argues that in all likelihood the kava plant was known to the first settlers of Aotearoa. It is also possible that (just like the Polynesian migrants that settled in Hawaii) the Maori explorers brought some kava with them. Unfortunately, most of New Zealand is simply too cold for growing kava and hence the Maori settlers lost their connection to the sacred plant. However, some traces of the memories of kava drinking have survived. 

According to Dr Lebot: "In New Zealand, where the climate is too cold for kava, the Maori gave the name kawa-kawa to another Piperaceae, M. excelsum, in memory of the kava plants they undoubtedly brought with them and unsuccessfully attempted to cultivate. The Maori word kawa also means "ceremonial protocol", recalling the stylized consumption of the drug typical of Polynesian societies". 

Kawakawa is related to kava, but unlike its tropical cousin, it doesn't have the famous relaxing properties. However, it has traditionally been used for various medicinal and practical purposes. According to Te Papa Museum: "Kawakawa has been recorded as being used internally to tone the kidneys and help with stomach problems. Externally it was used for cuts, wounds, boils, abscesses, and nettle stings. It was also used for rheumatism and other aches and pains including toothache. When kawakawa is thrown on a campfire and burnt it reputedly keeps mosquitoes away."