Journal Number 113
August 2009

ORIGINAL PAPERS

Southern Summer Orchids
By Gael Donaghy

With five weeks holiday during Dec 2008 - Jan 2009, Graeme and I chased fine weather and orchids
from Farewell Spit to deep Fiordland.

First serious hunting was for Pterostylis puberula and P. tasmanica, around Pillar Point, in a wind that was hard to stand up in at times. Here we were rewarded with many Thelymitra and Pterostylis alobula and, clearly identifiable by the leaves and hairy stem, one P. puberula.

En route south, we stopped briefly at the Boyle River, on the Eastern side of the Lewis Pass, one of our happy hunting grounds when we lived in Nelson. The weather was not kind on this day, and we walked briefly up the access track for 20 minutes or so in the pouring rain. We were rewarded with scattered flowers of Caladenia chlorostyla (both green and red stem variants) and C. lyallii.

Further south, we botanised a friend's covenanted area at Tuapeka West, across the Clutha River from the Blue Mountains. In the past I was sure I had seen either Corybas cheesemanii or C. cryptanthus in deep litter under an old Nothofagus solandri.

But alas, although the owners, keen botanists, were able to take us back to the spot, the tree had died, and without it to pump the water out of the ground, it had become boggy and unsuitable. So I will never know! Still, elsewhere we were tantalized by plants of a smallish Pterostylis aff. montana with flowers largely over.

After Christmas with family, our target was the Dusky Track. Initially, the weather was very wet in Fiordland, so we spent time around Cromwell. Here we kept coming across a Corybas under tussock on the tops, always in very damp areas. We found it up the Roaring Meg (Fig 6), in a high basin below Mt Pisa, and on a hill above the Old Dunstan Rd on the Eastern side of Lake Dunstan.

Figure 6

We have also seen it as far south Mt Eldrig (off the Borland Saddle Rd) and the Hump Ridge, usually above 5000 ft. But always without flowers, sometimes in seed. Was this the Corybas "tussock" we had photographed in flower at Island Pass in Marlborough (and Bruce Irwin had illustrated for the NZNOG Journal)? Only flowers will tell.

In the last week of my stay, a big anticyclone promised fine weather for a week, so finally we hired a helicopter to fly into Lake Roe hut, just above bushline on the Dusky Track (Fig. 7).

Figure 7

It was a great base to explore the Pleasant Range, which lies to the West of the hut, and the Merrie Range which lies to the East, towards Lake Manapouri. Orchids flower later here, with the second week in January about peak flowering for many.

In the tussock we found a few pale Caladenia lyallii (Fig.8), some Aporostylis bifolia in late flower, and many Wairea stenopetala, which ranged from tiny miniatures with one flower to large plants about 40cm in height, with up to four flowers. The mystery Corybas was also ubiquitous there - found only by parting the heavy tussock in wet mossy seepage areas (Fig.9).

Figure 8		Figure 9

The vegetation seemed in good condition, with little evidence of damage from deer. There were mountainsides of Mt Cook lilies (not yet in flower), lovely swathes of both the bright yellow Dolicoglottis lyallii and the white D. schorzonioides, and pale yellow hybrids. The unusual native anemone was common, and the flowers were a striking brick red. After the orchids the best find was a lovely shiny yellow buttercup with cut leaves, like parsley.

The following two day walk out to Lake Hauroko to catch the boat was also rewarding. In the wet bush, we saw many Aporostylis bifolia perched as epiphytes, including one group at least 5m up a beech tree (Fig.10).

A few Adenochilus gracilis were still in flower, and many, usually solitary Caladenia chlorostyla (Fig.11) in flower, were scattered along the track. Also, two Gastrodia cunninghamii plants were spotted in flower (Fig.12).

Figure 10	Figure 11	Figure 12

Most of the Pterostylis banksii were over, but P. australis still had quite a few good flowers in the colonies. (Fig.13).

Figure 13

The most interesting find was a Pterostylis in a boggy clearing where we stopped for lunch.
It was highly coloured which made me think of P. irsoniana, but there was no callus on the tip or
base of the labellum (Fig.14-16).

Figure 14	Figure 15	Figure 16

There were many juvenile (non flowering plants), and about half a dozen in full flower.
The closest call is another P. aff. montana? Further on we found more typical P. aff. montana (Fig.17).

Figure 17

This was my third trip in this area; the previous two trips were before I had much knowledge of our wonderful flora. I feel really privileged to return to these areas with Graeme and see them with "botanical eyes".