Alpine tussock grass lands of Southern NZ – an imaging project for 2023

Fujifilm, thank you for your time.

Some background: fifty plus years in the New Zealand mountains. In the early ones I was a mountain guide, and heliski guide in the winters. This flowed on into geophysics field work in NZ and Antarctica. And then spasmodic volunteer work for NZ’s Dept. of Conservation. And in the last several years contract field work for them, and then two years in a governance role. Being a voice for the public and our native birds.

In New Zealand alpine grasses are often referred to as snowgrass.

Significant areas, both large and medium in size, are in steady decline. Historical records note that they were once at least waist high. Not only in Mackenzie Basin, but also Otago and Southland. All typical New Zealand high country sub alpine environments.

The main reasons have been the Europeanisation of the landscape. Usually to further the goals of agriculture. Coupled with the introduction of rabbits many decades ago. Large rabbit numbers depleted ground cover. And then an invasive weed called hawkweed (Hieracium lepidulum) took over.

Which leaves bare ground! Then, with the help of winter “frost heave”, soil blows away in the strong winds New Zealand is renown for. Thus habitat for what is a very robust plant, is disappearing. As the decades go by there is a deficit.

NZ Heritage Landscapes are disappearing!

All photos by the applicant Donald Lousley, Wanaka, New Zealand. Thanks to Victoria Uni. website for help with the words. And to Soil Conservator Alistair Shearer, contractor to Environment Canterbury; and Rob Phillips SEO (recently retired) of Environment Southland for support/ideas.

Snow Grassess

The larger alpine tussock grasses, or ‘snow grasses’ as they are called, are frequently a metre high and sometimes as wide. Under good conditions they may reach head height at up to 2 m. Growth is slow and some of the larger specimens are estimated to be several centuries old

Depletion

This, now protected, Oteake Conservation Area shows historical degradation. Due to extremes of climate though, regeneration will not be quick. If at all.

The same area in winter

A healthy spot

The colour of a snow tussock landscape is generally not green, but, depending on the species, ranges from a pale straw colour through shades of brown to a distinctly reddish shade. The lack of greenness results partly from the regular dying back of the leaves from the tips and partly to the presence of masking pigments.

Variety in a harsh environment

An important part of the sub-alpine flora is a wide diversity of herbaceous plant species. And also in some instances beech trees.

Sunset and wind at higher altitude

The more or less hemispherical form of many of the snow tussocks confers on the mountain slopes a very distinctive and attractive texture reminiscent of that of cirrus clouds or, when the tussocks are tossed by the wind, waves at sea.

Hieracium aka hawkweed, the yellow flowers present amongst tussock at higher altitudes. So far in balance, and this may with luck persist. The small hut (restored) was once shelter for those in the profession of being a “rabbiter”. And due to the scale of this landscape horseback was the usual means of access. But not in the winter months.

Known as Turtle

Slow and able this is the applicant’s preferred means of accommodation while gathering images.

The areas where tussock is holding it’s own is still host to many activities such as, in this instance, gold mining. This is a more historic example, but there is a discreet environmentally sensitive operation nearby that utilises more modern plant.

A sample of species, all endangered, that frequent tussock/snowgrass environments

New Zealand’s highly intelligent and mischievous alpine parrot the kea. On a bad hair day!
Mountain stone wētā are long lived and are found on many central mountain ranges in New Zealand’s South Island. Over the cold winter months, this species of weta can survive being frozen solid at temperatures of -10 degrees Celsius for up to 17 days duration.
Post glacial landscape, New Zealand Like many areas in the world glaciers have sculptured and carved the landscapes we see today. They all scrape away the softer rock and sediment beneath them. As the ice melts during a “retreat”, it will drop rocks, sediment, and debris once carried on the surface of the ice. Unlike a river, glaciers only drop their cargo when they melt. In this case further “weathering” has also occurred. Forces such as rain water run off and frost heave of soils/clays come into play. Due to altitude induced coldness, not much grows. But there is evidence of these areas in New Zealand once being home to totara forests. The cover in this photo is a resident tall grass known as snow grass. Also known as red tussock.

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