Kowhai in bloom

For years, I have been meaning to photograph kowhai's spring flowering display at Wenderholm whilst it is at its peak. A particularly fine northern species, Sophora chathamica, projects from the bush on this coastal hill, reaching its greatest abundance on the bush margins. At the time of my visit (during the previous weekend), the trees were alive with tui and kereru, who were feeding on them.

Sophora chathamica differs from the better-known S. microphylla in not having a divaricate juvenile phase, as well as having relatively large leaves with crowded leaflets. It is a species that should be much more widely grown in the north of New Zealand, to which it is native despite its slightly misleading name.

The specific epithet 'chathamica' refers to its occurrence on the Chatham Islands, where it may be native or the result of deliberate planting by Māori. Intriguingly, this species is predominantly found in the northern half of the North Island, with disjunct populations in Wellington, northwest Nelson and the Chatham Islands.

This unusual distribution has led to a well-considered theory that the southerly and Chatham Island populations may have brought to these areas by Māori - an idea that I find understandable, on account of the fine characteristics of S. chathamica (people have always moved around especially good forms of plants in association with our settlements).

Kereru (as pictured, above left) feed on both the leaves and flowers of kowhai, whilst tui are solely interested in the nectar of the flowers (whose form is clearly adapted to receive the attentions of nectar-feeding birds).