[an error occurred while processing the directive]
  [an error occurred while processing the directive]  

The Beautiful South

Island, that is. Of New Zealand, where grows one of the most attractive of all the near-hardy palms, the Nikau. Grab your shaving brush and meet Peter in its most southerly habitat there.
Peter Richardson, c/o Advanced Technologies Ltd., Science Park, Cambridge
Chamaerops No.22, Spring Edition 1996

[an error occurred while processing the directive]

Photo: the author, with Dicksonia for scale

In view of the viciously cold winter we have just had, I thought this year I would go spore and seed collecting to the southeast corner of New Zealand to maximise the chances of bringing back material that was actually going to be hardy in my garden in the UK. Two targets I had for this trip were to visit the southernmost Nikau Palm colony on the South Island which is on Banks Peninsula about 84km from Christchurch, and to collect treefern spores from the southern end of the Island.

The Nikaus are in a reserve called Palm Gully reached by a footpath several kilometres long from Onuku, a hamlet south of Akaroa, a picturesque French colonial town. It is administered by the Department of Conservation who have "closed" it for the present because it is considered dangerous, although there is no physical closure of the reserve. It is an extremely precipitous ravine facing out over a cliff to the sea on the east side of Akaroa harbour entrance facing south (i.e. away from the sun, equivalent to 'north-facing' in the Northern Hemisphere), and reminiscent of Cheddar Gorge in Somerset UK (though the rocks are volcanic, not limestone) .

The bottom of the ravine is densely wooded, mainly with Fuschia excorticata and Melicytus ramiflorus, and of course the Nikau palms, some of which also cling to the steep sides of the valley above the wood. These are the southern type, and their fronds have very sturdy rachises and spread out at about 45 degrees. Under the shade of the trees, the young plants are deep green and lush, leaflets broad and arching outwards. With the variety of Aspleniums and Blechnums also present, and a stream splashing down over large rocks it has a delightful, subtropical look.

In fact I found it a puzzling place. The sun barely rose above the cliffs at the back of the ravine when I was there at the autumn equinox, so throughout the winter the gully must be sunless, and as it faces out to sea it is open to winds coming up from the Southern Ocean and Antarctica. It seems odd that this palm should choose such a cold, sunless microhabitat at the southern extreme of its natural distribution. There are hundreds of Nikaus of all ages in the valley, but when searching adjacent valleys for others I only found two scraggy old specimens in bushy grassland grazed by sheep. I suspect that the reason for their abundance in Palm Gully is simply that its precipitousness has protected it from agricultural activity. All the surrounding valleys are part of a sheep farm.

The palms do not show signs of bad frost damage. They grow to the same height and stature as elsewhere and are flowering profusely and fruiting without regard to the seasons as they do further north. The ground gets a steady rain of ripe drupes, picked at by the birds, and, in the deep shade of the broadleafed trees, there are hundreds of small grassy seedlings. Overall, this palm colony does not present the appearance of a plant at its climatic limit.

Later when driving on southwards I was to find that Phoenix canariensis is grown 500 km further south in Dunedin. I saw two specimens in suburban gardens there, one adolescent and one mature and flowering and fruiting. This also suggests that Rhopalostylis could be capable of growing further south than Banks peninsula; however the Canterbury Plains which extend north and south of the peninsula have a long history of human disturbance, having been almost fully cleared of forest by the Maoris, even before white settlers arrived.

I also spent three days looking round the southeast coast of the South Island, an area known as 'the Catlins', at around 46 degrees south. This part of the island is much drier than the west coast, and not as mild in the winter. Naturally occurring Cordylines are absent from this area but two hardy treeferns are found widely, Cyathea smithii and Dicksonia squarrosa. Both are shaderequiring species and are common under mixed forest at low altitudes. Even these are absent from the coldest forests, which consist solely of Nothofagus at higher elevations inland.

I walked up a track known as the 'Back Stream Road' into these mountains, within Catlins Forest Park, from near Tahakopa. C.smithii was the treefern that I found extending up the furthest, with a few sporadic plants even in the pure beech forest above 500m. These isolated specimens were comparatively short and entirely lacked fertile fronds, at least this year, and I could only collect spores from lusher groups further down.

Treeferns, when they finally get around to producing spores, bear them in huge numbers and it is only necessary to take two or three side pinnules of one leaf to end up with a decent sized spore sample. Mine are now germinating.

I found fertile fronds of Dicksonia squarrosa even scarcer; the only ones I found were on plants that had been left when a block of bush just south of Papatowai had been cleared for sheep pasture, leaving them out in the full sun - and their sporangia were not ready to release their spores. There are patches of amazing fern forest in the old stabilised sand dunes immediately behind Tautuku Beach, where D. squarrosa has gained supremacy over all other vegetation by suckering. Sheltered from the blasts of sandy, salty wind off the Southern Ocean only by a ridge of marram-covered sand, the trunks of the mature plants are three to five metres high. The ground is lost beneath criss-crossed fallen dead fern trunks, and new suckers continually rise through them to greedily occupy any free space. Woody plants are relegated to the role of epiphytes, perching on the ferns' trunks along with filmy ferns and a fragrant orchid, Earina autumnalis; sublime exoticism at a latitude equivalent to that of La Rochelle - certainly worth travelling to the far side of the planet to see.

Readers Comments:

(No comments yet. Be the first to add a comment to this article!)

 Your comments:    The Beautiful South 
    Add your personal thoughts, comments, ideas, suggestions, experiences etc. to the above article. Just fill in the fields below:
  Check this box if you do not want your name and e-mail address to be published.

(please allow a few seconds for response)



[an error occurred while processing the directive]