Sunday, March 29, 2009
Do not forget the natives!
For a long time botanists considered there was only one New Zealand species of kaka beak – Clianthus puniceus, found in East Cape and northern Hawke’s Bay, and also in isolated places in Northland, where European scientists first found it. Maori had long treasured it for its red flowers.
That view has now changed and botanists say there are two species – the critically endangered Clianthus puniceus which is now found in only one place - Moturemu Island in the Kaipara Harbour - and the only slightly less endangered Clianthus maximus, which is found in the East Cape area, in a small number of sites.
This second plant is the one most commonly met with in gardens, although often described as being the first named species. By far the most usual form is ‘Kaka King’, a selected East Cape variety, cutting-raised and all stemming from one wild plant.
The number of plants found in the wild is plummeting remarkably. In 1995 over 1000 plants were found growing naturally. A decade later the number had fallen to just over 150.
So what is happening?
The plants threatened status is due to two factors – changing environmental conditions, and excessive predation.
In the wild, these plants are early colonisers of bare ground, often being among the first plants to invade slips and other gravelly sites. Over time they get shaded out by taller growing species like tutu and kanuka, but there is always fresh ground to invade.
The young seedlings are soft and succulent, as anyone who has grown these native treasures from seed will know. This has made them very prone to predation from deer, which browse the screes and slips the kaka beak once colonised. And goats, which are an increasing pest in the East Cape area, also love to eat the young plants.
At first glance it would appear that gardeners could have a part to play in keeping kaka beak safe for the future, but it turns out to be a faulty concept. Unfortunately, almost all the plants grown in the trade are grown as cuttings, and thus there is a very much reduced gene pool.
The answer has to be action in the wild. One programme has seen school children planting thousands of seedlings on the roadside, and a journey through the East Cape in October is enlivened buy the site of strips of the bright red flowers of kaka beak.
That is not to say we cannot help. Some nurseries are now starting to raise plants from seed rather than from cuttings, and, as many gardeners will tell you, kaka beak plants will set seed in the garden, and germinate well in light, open soil.
In the garden these plants do best in full sun – remember they die out if planted in the darkest depths although they can cope with light shade. They prefer well worked soil, preferably well-drained, and should be kept out of strong winds. They can a slightly frost tender, but should cope with most sites in the lower North Island.