Post-bushfire resurrection of the Bolivia Hill Pimelea

Post-bushfire surveys near Tenterfield, NSW have uncovered more than 800 seedlings of the Bolivia Hill Pimelea, an endangered shrub previously thought to be extinct in the wild.

Pimelea vensosa (Bolivia Hill rice-flower) flowering

NSW Government Saving our Species Threatened Species Officer Todd Soderquist said the discovery of the seedlings was extraordinary after nearly a decade passed without any sightings of young plants.

"The Bolivia Hill Pimelea, or 'rice-flower', used to be widespread on the Northern Tablelands," said Dr Soderquist.

"Sadly, these small, isolated populations declined one by one until 2017, when the last known mature plants on a private property gradually died out and extensive searches failed to locate any seedlings.

"Following the 2019–20 summer bushfires which burned across the region, Dr Soderquist and the landholders resumed the search for the endangered plant, hoping to find some signs of recovery. Incredibly, they were rewarded with a dense germination of new seedlings in July.

"These seeds have been lying dormant in the soil for years and were triggered to begin germinating by low-intensity bushfires, which removed competing plants, and the subsequent consistent rainfall.

"Our focus now is to protect these seedlings. The landholders are controlling feral goats on their property and we've erected enclosures to provide additional protection for the seedlings from wallabies and kangaroos.

"We're also undertaking an extensive monitoring and research program with the Royal Botanic Gardens, the Australian National Botanic Gardens and two local nurseries to understand the ecological requirements of the Pimelea and identify the best methods to stimulate seedling recruitment year after year.

"We're optimistic these actions will ensure the long-term recovery of this species in the wild," said Dr Soderquist.

In 2014, the NSW Saving our Species Program took emergency cuttings from the last remaining individuals to establish an insurance population with the four nurseries.

The translocation of members of this insurance population to Bolivia Hill Nature Reserve is planned for 2021 now that post-drought rain in the region is predicted to be adequate to establish the plants.

The Bolivia Hill Pimelea is an upright shrub, with soft, white hairs densely covering its stems and leaves. The shrub typically grows to around one metre high. Small white flowers appear in late winter, sometimes covering the entire plant so completely as to resemble snow.