TRIP REPORT : Western Ruahine Range

 Saturday – Friday – Monday :   21 – 24 March 2008

Leatherwood / Olearia colensoi.   Illustration by Bryan Halliday.

After settling in at Sixtus Lodge in the Pohangina Valley, we spent the afternoon botanising the foothills near Coal Creek, in beautiful weather which lasted throughout Easter.   Under tall, red beech, we noted numerous Alseuosmia pusilla with crimson ‘jelly bean’ fruit.

Day 2, 22/3/08
We set off to climb from Coal Creek to the Ngamoko Range, via Shorts Track.   Forest cabbage trees were unusually plentiful, and mountain cabbage trees were prominent, thrusting their unmistakable, spiky crowns into the canopy.   Other highlights were a pink pine, Halocarpus biformis, 60cm d.b.h., and in the leatherwood belt, Pittosporum rigidum and Euphrasia cuneata in flower.

Above the bushline, with a clear view up the spur, we were dismayed to see large numbers of emergent stagheads of Libocedrus bidwillii.   This forest is near collapse because of browsing by pest animals, including deer and possums.   We noted deer browse even on carex, uncinia, broad-leaved bush tussock, and bush rice grass, which are not often browsed.   Extensive areas of crown fern, mountain horopito, and bush rice grass, all unpalatable species, and the scarcity of palatable species such as tree fuchsia and hen and chickens fern, indicate the serious plight of this montane forest.   It is in desperate need of regular, intensive, pest animal control, by all means available.

Near the bottom of the descent to the Deerford Loop track, above the TL of Coal Creek, we saw an extensive area of total dieback of kamahi and red beech.   Was this the result of the cumulative effects of drought, possum browse, insects and disease?

Day 3, 23/4/08

From the carpark on Petersons Rd, we botanised in the Oroua River valley towards Heritage Hut, where we had lunch.   We continued up valley on the ‘high water’ track, to the point where it zigzags steeply down to a TL tributary of the Oroua River, making about forty-five additions to the plant list, including narrow-leaved mahoe, black beech, Clematis foetida, and lace fern, Leptolepia n-z.   The weed, catmint, Nepeta cataria, was abundant on the zigzag, and we pulled out buddleia in the flood-ravaged gully of the tributary.

Day 4, 24/4/08

After packing, and tidying Sixtus Lodge, we drove along Pohangina Valley East Rd to Makiekie Scenic Reserve, perched on bluffs on the True Right bank of Horopito Stream.   Mick spotted a “hole in the edge of the scrub”, near the bridge – the start of a pest control line with about 20 bait stations.   We clambered up to the top of the bluffs, and entered impressive podocarp forest with large totara and rimu – truly worth pest control.

We drove down valley to lunch by a large totara in Pohangina Scenic Reserve.   This forest remnant was suffering from severe desiccation – seldom had any of us seen a forest with such widespread wilting.   No doubt the drought, plus the narrowness of this remnant, river-terrace, forest, and its exposure to ‘edge effect’, accounted for its sad appearance.

We thank Sixtus Lodge Trust for the use of their excellent facility, Graeme Jane for supplies of plant lists, and John Sawyer, DOC, WN, for copies of Tony Druce’s plant lists 148 and 124.

Participants :   Bev Abbott, Bryan Halliday, Chris Horne, Graeme Jane, Brenda Johnston, Sheelagh Leary, Rodney Lewington, Barbara Mitcalfe, Mick Parsons, Darea Sherratt.

Barbara and Chris