A team of botanists and conservationists has planted around 250 seedlings of one of New Zealand’s rarest plants at a Central Otago reserve this week, marking what the Department of Conservation has called an eleventh hour rescue of a species that had dropped to just two known wild specimens.
The plant, Craspedia argentia, is a silver-leaved woollyhead herb that is endemic to the dry tussock plateau of Pisa Flats above Wanaka. Its population had collapsed so far that conservation staff feared they were watching the species blink out in real time. By the time the recovery programme began, only two flowering plants remained in the wild, and the pollination network the species depended on had already broken down around them.
The seedlings were planted at Mahaka Katia Scientific Reserve, with the work led by Department of Conservation senior technical adviser in ecology Richard Ewans. He told RNZ the team had moved quickly because the alternative was loss.
“We’ve been really concerned about this plant disappearing,” Ewans said. “So we knew we had to intervene and start a programme of breeding.”
The first propagation season, run through Dunedin Botanic Garden, was more successful than the team had dared to hope. Ewans said staff produced about 800 seeds from those first two parent plants, and that early yield turned into roughly 300 seedlings ready for trialling. The 250 seedlings put into the ground this week were drawn from that pipeline, and a second wave is being readied for future plantings.
Otago botanist Geoffrey Rogers, who has spent decades studying the rare flora of the region, said the scale of the recovery against such a tiny starting genetic base was remarkable.
“All of these plants going back into the ground, now hundreds, were derived from those two plants,” Rogers said.
The careful work of raising seedlings from a thimble of seed has fallen to a small group of growers in Dunedin and Alexandra. Apprentice horticulturalist Jess Freeman, who has been part of the project at Dunedin Botanic Garden, described it as a slow nursery task carried out over many months.
“We’ve just kind of looked after the babies, nursed them up, counted seed from them,” Freeman said.
Botanist Tom Myers, also from Dunedin Botanic Garden, said the project had reinforced for him how distinctive Central Otago’s plant communities are. “It really speaks to me of this habitat. Like I’ve always loved coming through Central Otago,” he said.
Some of the propagation work has been done well away from any formal nursery setting. Dhana Pillai, a home-based propagator in Alexandra, has been raising plants in her own garden under the project’s guidance.
“It’s really great to be part of this project,” Pillai said. “I’m learning so much about these plants.”
Craspedia argentia is part of a wider group of Pisa Flats specialists that have struggled as introduced grasses, browsing animals and changes to the high country’s natural fire and grazing patterns have squeezed native cushion and tussock communities. Many of these plants are tiny, slow growing and highly localised, which means a population loss in one valley can mean a global loss for the species. Conservation staff say the woollyhead herb is the most acute example of that pattern, but it is far from the only one.
The Mahaka Katia Scientific Reserve was chosen because it offers the right kind of dry stony habitat the species needs, while also being managed for biodiversity rather than grazing. The reserve has become a working laboratory for restoring Pisa Flats plant assemblages, and the woollyhead release fits inside that wider effort rather than standing alone.
For the next few months the team will be watching the new seedlings closely. Department of Conservation staff plan monthly site visits through winter, supported by trail cameras to track any browsing pressure or weather damage. The real test will come over summer, when the young plants must hold on through Central Otago’s heat and dry winds and put roots deep enough to keep them alive into a second season.
If the seedlings survive their first summer, the project’s organisers hope to keep building the population each year, so that the species moves from being two plants away from extinction to a genuinely self-sustaining wild population. The aim, Ewans has said, is not just to keep Craspedia argentia on the books as a name in the threatened species list but to put it back into the landscape it evolved in.
Conservation funding for this kind of intensive single species rescue is always limited, and the project has relied heavily on the combined efforts of Department of Conservation staff, the Dunedin Botanic Garden team, independent botanists and volunteer propagators. The pattern of partnership has become more common as agencies stretch resources further, and Pisa Flats is shaping up as a case study in what that mix can deliver.
The full RNZ report on the planting carries more from the team on site, and the Department of Conservation maintains background on the country’s threatened plants and their conservation status.
What do you think of intensive single species rescue projects like this one, and which Central Otago native would you like to see brought back next? Leave a comment below.
This article was written by AI, briefed to report the facts, hopefully without some of the bias people bring to the job 🙂
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