May - Kawaka - Native Plant of the Month
Updated: Jun 13, 2022
Kawaka are gateway trees into the world of Aotearoa’s plant diversity. They are the perfect native tree for people who are more comfortable with the aesthetic of exotic garden plants and groomed parklands. They look like a conifer that would be at home amongst the pines in the Northern Hemisphere, but they are native trees in disguise! Kawaka have appeal to those already converted to the joys of our native heritage too - they are naturally uncommon trees that have a beautiful form and are strikingly growing on their own as specimen trees, or amongst others in the bush.
Did you know that we have two native species of cypress? Kawaka and their alpine sisters pahautea are endemic trees that are both listed as naturally uncommon. They have a distinctive and unusual appearance that makes them look exotic within our bush - they are so different to any other of our native plants. Kawaka belong to the genus Libocedrus, which roughly translated means 'frankincense cedars’ and describes the spicy fragrance of their resinous wood. This is a small genus with two New Zealand species and three others in New Caledonia. Despite their own name describing them as a cedar, kawaka and other Libocedrus species are actually more similar to cypresses (due to the shape of their leaves) and so kawaka and pahautea are sometimes called New Zealand cypresses.
Kawaka can be found in the top third of the North Island as well as the very top of the South Island. Kawaka are a naturally uncommon species as they require disturbance, such as a landslide, to regenerate and prefer to grow away from other native trees (exactly the conditions that a newly bare patch of soil from a slip creates!). Despite preferring to grow away from other trees, kawaka have been described as gregarious - they do like to grow together! In the North Island kawaka often grow in association with kauri too, particularly along ridgelines. However, they can be found growing further south than kauri’s southern limit and it is thought that there was once an area of forest where they were the dominant canopy tree in the western Waikato. Unfortunately, kawaka have become even more uncommon in recent times as their red-grained timber was considered very useful and so they were selectively logged out of many of their original sites, including the Waikato forest.
The scientific species name for kawaka is plumosa and this is a lovely description of their foliage. Plumosa means feathery and fronds of kawaka leaves have a beautiful feathery, ferny appearance as they grow in one flattened plane. They are a bright green colour, sometimes with yellow tones that make them contrast beautifully with the mostly dark-green leaves of our other native canopy trees. Kawaka branches grow in graceful horizontal layers, and they are usually neatly symmetrical, forming pyramidal or conical shaped trees. They have an elegant tidy form at all ages, which makes them ideal native potted Christmas trees! They also make superb specimen trees (perhaps once they are retired from Christmas duties).
As kawaka mature the bark on their trunk becomes a feature in itself - it is a deep warm brown and peels away from the trunk in large pieces that look like shards of chocolate. It is hard to keep the music from the ad for a certain crumbly chocolate bar out of your head while looking at them! This flaky bark is an ideal habitat for all sorts of small native species and you will often see birds rummaging about for insects up and down their trunks. This loose bark could also be used as a roost site by our native bats! Kawaka are very unusual among our native trees for having woody cones which contain their seeds. While we have plenty of native trees that are in the large conifer plant family, all but two have modified their cones into fleshy berry-like forms. Kawaka cones are small and beak-shaped with little woody spurs near their bases and grow near branch tips through summer and autumn.
Kawaka prefer to grow in rich, moist and free-draining soil and are happy to grow in the open, or partial shade. Once they have established strong roots they are quite hardy trees and so they are suitable for most sites with a little care and summer watering in their first few years. We would love to see kawaka used in place of conifer species in formal gardens or public parks. There is a beautiful large specimen growing just before the entrance to the bush tracks in the lovely Fernglen Gardens, which we highly recommend people visit!