Piper excelsum (formerly known as Macropiper excelsum), commonly known as kawakawa, is a small tree of which the subspecies P. excelsum subsp. excelsum is endemic to New Zealand; the subspecies P. e. subsp. psittacorum is found on Lord Howe Island, Norfolk Islandand the Kermadec Islands.
The leaves are often covered with holes caused by the caterpillar of the kawakawa looper moth(Cleora scriptaria).
Kawakawa flowers are quite minute and very closely placed around the spike. After pollination the flowers gradually swell and become fleshy to form small, berry-like fruits that are yellow to bright orange. Each berry cluster is the size of a small finger. Ripening period is January and February. These fruits are favoured by kereru and tui .