Baeuerlen's Gentian

The native subalpine herb Baeuerlen’s Gentian (Gentiana baeuerlenii) was declared an endangered species in the ACT in 1996. It is listed as endangered nationally and in NSW.

The species was probably once widespread, but the only known ACT population was discovered in 1991—just one site of 20 plants at the Orroral Valley in Namadgi National Park. Although no plants have been found at the site since 1998, when fewer than 10 plants were observed, they are not yet assumed to be extinct and there is the possibility other populations may exist.

Baeuerlen’s Gentian is a small annual herb that grows 2–4 centimetres high. Each flower is bell shaped with five petals that are greenish outside and blue-white inside. The herb flowers between March and June.

The species was found in the inter-tussock space of moist tussock grassland and sedgeland associated with ground water, possibly a spring-fed area. The site is probably secondary grassland or a relict grassland opening that was once surrounded by open woodland. It sits on the lower slopes of a broad valley, above a river.

Because the species is associated with the more widespread Spiranthes sinensis orchid, the Ranunculus pimpinellifolius herb and the Hemarthria uncinata grass, these species may be indicators for other potential sites.

Conservation threats

It is likely the species was once widespread but was impacted through land clearing and grazing. It was particularly vulnerable in times of drought; the areas in which it is found would have remained grassy well into the driest seasons and been trampled. Although chemicals in the plant make it distasteful to stock, it could have been inadvertently grazed with other species. Being fairly remote, the Namadgi site could have escaped pastoral damage.

Before being fenced in 2002, the site was damaged by pig rooting. The valley was severely burnt in the 2003 bushfires. It is not known whether less severe fire may benefit the species or whether native grazing animals such as kangaroos pose a threat to survival of remaining plants, or benefit the species by keeping competing grass tussocks and other plant growth short and open.

Conservation actions

Through the Baeuerlen’s Gentian Action Plan (2017) and the ACT Native Grassland Conservation Strategy (2017), the ACT Government proposes to maintain the conditions, in the long term, that encourage a viable, wild population.

Conservation actions to date have aimed to maintain existing conditions at the known site and ensure nearby activities do not adversely affect the site. For example, there has been no walking or vehicle track development near the site. While stock have been excluded, kangaroos have been able to graze in the area. Carefully managing adjacent grassland may encourage any existing plants to establish new populations.

Options such as grass trimming and burning have been investigated to reduce build-up of grass that may hinder germination. Some minor physical removal of weeds and grass thatch is carried out during annual site assessments in May/June.

While conducting vegetation surveys in other suitable habitat, researchers and park rangers keep an eye out for the species.

Further research is required, but cannot be conducted until more plants are found. Only then could plants be propagated or seed collected and research conducted on appropriate methods for managing the species and its habitat, vegetation biomass, lifecycle, germination, recruitment and genetics.

More information

Contact

Epsddcomms@act.gov.au or call Access Canberra on 13 22 81