Story: Tall broadleaf trees

Girdling roots of northern rātā on a rimu tree

Girdling roots of northern rātā on a rimu tree

Northern rātā normally begins life as an epiphyte (perching plant) high in the branches of a host tree. As it grows, the plant sends roots down to the ground to get water and minerals. Eventually the descending roots widen in girth, become woody and form a supporting trunk for the mature northern rātā. A descending root can be seen to the left of the rimu trunk. Northern rātā also produces girdling roots, which encircle the trunk of the host plant. These help stabilise the descending roots as they grow thicker and provide support. The grooved descending root on the right of the rimu trunk belongs to the epiphytic shrub puka, Griselinia lucida.

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Te Ara - The Encyclopedia of New Zealand
Photograph by Melanie Lovell-Smith

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How to cite this page:

Maggy Wassilieff, 'Tall broadleaf trees - Tree rātā', Te Ara - the Encyclopedia of New Zealand, http://www.TeAra.govt.nz/en/photograph/13709/girdling-roots-of-northern-rata-on-a-rimu-tree (accessed 28 February 2020)

Story by Maggy Wassilieff, published 24 Sep 2007