Even scrubby riverbanks can be interesting.

Today we travelled from Picton to St Arnaud in Nelson Lakes National Park.  The road follows the Wairau Valley, which is formed along the Wairau Fault.  The Wairau Fault is a northern extension of the New Zealand Alpine Fault, a huge transcurrent fault that has separated rock formations on either side by 480 km in the few million years it's been active.

We had to stop at a swimming hole in the river at the Kowai Point Reserve, and it's just as well we did, because our trusty bus had developed a diesel leak.  So the students had a swim and I sat in the shade swatting blackflies.  Right there was a native Rubus in fruit:

Rubus is a genus of famous eating fruits: blackberries (serious weeds in New Zealand), boysenberries, cloudberries, and the like.  Sadly our native ones aren't so great.  These tasted like ordinary plant matter, neither fruity nor sweet, and there was almost no pulp around the seeds.  Maybe they trick birds into eating them, but then the birds fly off in fright, spitting out the seeds on the wing.  Or maybe not ...

After sitting under the shade of a kanuka (Kunzea ericoides) for an hour or so, I eventually noticed a small green mistletoe, Korthalsella, on a low branch, then another, and another.  In all there were 20 or so in a small area.  These have scale leaves and lack the spectacular red or orange flowers of some other native mistletoes like Peraxilla and Alepis.  Research by Dave Kelly and Jenny Ladley at University of Canterbury has shown those (see below) are pollinated by birds and small bees, which have to learn to twist the buds to pop them open.

Alepis flavida, taken on the 2009 Lewis & Clark trip, near Arthur's Pass.

The bus is now fixed and we're settled in to accommodation at St Arnaud; tomorrow we're climbing Mount Robert and the students will be devising and planning group research projects.

Some plants from Shotover Saddle

Last week I went to Shotover Saddle in West Otago with Dr Heidi Meudt (Museum of New Zealand botanist).  We were collecting samples of Veronica and Myosotis for Heidi’s research, and I was there because I’d been before and knew the route.  Heidi is investigating the relationships and evolutionary history of these plants, using some of the latest DNA-based techniques.

Looking down to the Matukituki from about 3/4 of the way up.

It’s a long slog from the West Matukituki River to the top.  We were lucky because we had a rented four wheel drive and permission from Mt Aspiring Station to use the road beyond a locked gate.  Even so it was a long and tiring day.

The view across the valley, 1300m below, to Mt Rob Roy.

The only soul we saw all day was this paraglider pilot who flew along the ridge just above us.  We were told later he'd probably taken off from Treble Cone, near Wanaka.

The saddle (a common term in New Zealand for a pass or col) is the main access from the Matukituki to the head of the Shotover River.  It’s in Mt Aspiring National Park, so all our collecting was under permit from the Department of Conservation.

Veronica planopetiolata

Our main quarry was Veronica planopetiolata, a small glossy mat-forming plant of high altitude (1750m) scree, boulder field, and rock crevices.  It’s probably common enough in the Park and nearby, but not often collected.  When I did my PhD thesis (1975) on this group of Veronica, then classified as Parahebe (and here's an explanation for the change), I tried many times to collect some of this plant, but I never saw it in the wild until 2006.  It’s interesting because it’s tetraploid (has 4 sets of chromosomes instead of the usual 2), suggesting the possibility of a hybrid origin in its distant past.

Veronica planopetiolata with pink flowers

Most of the plants had white flowers, but some were pink (this photo was taken on my previous trip).

Veronica planopetiolata, like a lot of cushion-forming veronicas, has seed capsules that open when they're wetted by rain, and the energy from falling rain-drops splashes out the seeds.  My former student Gesine Pufal showed they don't disperse very far, and she concludes it's a way to restrict dispersal in plants that grow in very small habitat patches (Pufal et al., 2010; Pufal & Garnock-Jones 2010).  

Red Rock

This is quite a common plant on the scree below Red Rock, and in rock crevices and gullies nearby.  I’d expect it to be common at higher altitudes on Mt Tyndall and beyond, but getting up there is beyond my capabilities.

Veronica thomsonii

Other veronicas in the area include a hairy cushion snow hebe, V. thomsonii, a shrubby hebe (V. subalpina), and a whipcord hebe, V. hectorii.

Veronica subalpina

Veronica hectorii

The daisy or sunflower family Asteraceae is well represented in many parts of the New Zealand mountains.  The family includes a number of large groups, each of which appears to have evolved many species from an original founder.  There were more species than I’m showing here.

The Senecio tribe was represented by Dolichoglottis scorzoneroides and Haastia sinclairii, both of which are part of the Brachyglottis radiation in New Zealand.  Both these species had ancestors that were probably shrubby daisies.

Dolichoglottis scorzoneroides

Haastia sinclairii

The Aster tribe was represented by a large number of alpine daisies of the genus Celmisia.  Many Celmisia species appear to have wide distributions, so that on any one mountain there are often a large number of different ones, compared to Veronica, which has more species, but more localised distributions.

NZ edelweiss, Leucogenes grandiceps.

The New Zealand edelweiss has very similar flower clusters to its famous European namesake, but it’s classified in a separate genus and appears to have reached its similarities independently.  There are four species.  It’s much more closely related to other New Zealand genera in the Raoulia complex.

Craspedia

This woolyhead (Craspedia) is one of a baffling group of New Zealand plants.  Such is the variation in this group that botanists think there are a few dozen species still to be described and named.  There’s a lot of work to be done before we know this group in detail, and all the tools in the botanist’s toolbag will be needed to sort out the mess.

Wahlenbergia albomarginata

Wahlenbergia albomarginata, southern bluebell is a common plant throughout New Zealand (the North Island W. pygmaea is likely to be the same species).  It was common from the river bed up to Shotover Saddle, growing in grasslands, fellfield, and rock outcrops.

Schizeilema haastii var. cyanopetalum

Schizeilema is a small genus quite closely related to the giant Stilbocarpa of the subantarctic islands.

Ourisia glandulosa

A couple of mountain foxgloves were also of interest, because this group was the subject of Heidi’s PhD and several papers since.  This one is O. glandulosa.

Veronica thomsonii (top and left) growing in a single cushion with Myosotis pulvinaris (lower and right)

We saw two Myosotis (forget-me-nots), but only were able to collect one, because the other was just a single plant.  Myosotis pulvinaris is a cushion plant that looks superficially very like Veronica thomsonii.  The Myosotis differs in its bigger leaves and some details of the form and distribution of its hairs, and of course their flowers and fruits are quite different.  New Zealand forget-me-nots mostly have white flowers or sometimes yellow ones.

Looking west from below Red Rock.

References

Pufal, Gesine; Ryan, Ken G; Garnock-Jones, Phil.  2010.  Hygrochastic capsule dehiscence in New Zealand alpine Veronica (Plantaginaceae)  American Journal of Botany 97: 1413–1423.

Pufal, Gesine; Garnock-Jones, Phil.  2010.  Hygrochastic capsule dehiscence supports safe site strategies in New Zealand alpine Veronica (Plantaginaceae). Annals of Botany (doi:10.1093/aob/mcq136, available online at www.aob.oxfordjournals.org).

Shotover Saddle: not a route guide

I'll start with a disclaimer: this isn't an official route guide.  Rather, because I couldn't find a detailed route guide on line, I thought it'd be helpful to others if I described the way I've got up to Shotover Saddle, twice.

Shotover Saddle is a 1100m climb in about 2000m horizontally, so it's pretty steep tramping, but not climbing.  There are bluffy bits that are best avoided.  There was no available water when we did it (both times in February), but some of the gullies might contain streamlets after rain.  Take water, and a GPS is a very useful thing to have.

From the Land Information New Zealand website

The first thing to get right is the start of the route (A on the map).  You'll probably have come up the West Matukituki valley by 4WD (requires permission and a key for the locked gate), bike, or on foot.  The route we took begins about 1 km upstream from the prominent zig-zag in the 4wd track, right opposite the downstream end of a small island in the river bed, and across from a stream that drains a large shingle fan.  Another way to find it is to follow the main valley track across the side stream of the Bride's Veil waterfall, which is very prominent, and then cross two more small streams, although in dry weather these might not be very prominent.  There's a row of small wild Irishman (Discaria) trees along the riverbank, clearly seen in this photo looking down on the start of the route.

The lower part of the route, looking down from about 700m.

 So we left the main track there and headed south towards the fence, going between a couple of clumps of small straggly trees.  Across the fence, the next obstacle is a low bluff.  There seems to be a small ridge leading up it on your right, and you can get up that way although the sheep track narrows and steepens at the top; rather it's a lot easier to go around the bluff on the left, following the sheep tracks (B).  Once you're on top of this bluff it levels out briefly before the real climbing begins.  We went straight up here, sticking to the ridge between the two streams, past a few prominent rocks.  We used a GPS to make a waypoint each 100 m of the hike; we figured it'd help if we got fogged in on the way down.

We followed the middle of the ridge until we got to 900m above sea level.  From 900m, we had been advised to start sidling slightly towards the east, or left hand side, heading for a prominent small ridge that outcrops there (C).  From a clump of boulders in a ferny little gully at 1100m, you'll need to pick a way to sidle across a steep slope and onto this ridge, through a lot of spiny wild Spaniard (Aciphylla).  We did this by heading uphill a bit, then crossing the little gully and striking out to the left across a steep slope just above a couple of big boulders to meet the ridge above a prominent rock outcrop.  There are some sheep tracks through this bit and if you're lucky you'll find one of them.

Once on the ridge, it's easy going, although quite steep, for about 300 m, to reach a broad tussock-filled basin (D) that leads to the saddle.  Picking a route through it is quite straightforward; the important thing will be finding your way back to the right place on the ridge when you come down, so make plenty of waypoints on your GPS.

The tarn below Shotover Saddle

 Just below the saddle is a narrow small tarn (E); the water doesn't look very drinkable.  From here it's an short scramble up a steep tussock slope to the saddle.  Keep off steep slopes of Marsippospermum (a glossy green rush) because they're very slippery.

Looking down on the Shotover Saddle from the ridge to Red Rock.

 Getting back down is straightforward with your GPS waypoints, but it could be tricky otherwise, especially in fog.  Getting onto the little ridge and off it again in the right place is probably the key to it.  It took us about 3.5 hours to get up and 2.5 to get down.  If you're lucky to have a clear day, the views are spectacular.

Upper West Matukituki Valley from below Red Rock, looking towards Shovel Flat and Hector's Col in the distance.  Mt Aspiring is in the clouds on the right, behind Mt Rob Roy.