Dianthus superbus, commonly known as the superb pink, fringed pink or large pink, is a widely but patchily distributed perennial species in Europe and northern Asia. Although not considered to fall within a threatened category in Europe as a whole, the species is mentioned as a seriously threatened species in several European countries. In the Baltic States of Lithuania, Latvia and Estonia, the species has experienced decline due to changes in land use and agricultural intensification over the past century. This has resulted in highly fragmented populations with low genetic diversity. D. superbus is recognised as being on the verge of extinction in Latvia, however, there have been very few recent studies documenting the status of the species or considered the possibilities for its conservation.
In their new study published in AoBP, Osvalde et al. sought to inventory previously identified populations of Dianthus superbus in Latvia and to develop activities to conserve this species. In 2017, numerous expeditions were carried out to verify the data on all previously known locations in the country. Unfortunately, in most of these locations the species was no longer present. Existing localities were re-surveyed in 2019 and 2020. During the expedition in 2020, D. superbus was additionally searched for in Silenieki, in the east of the country, near the only locality in Latvia with a substantial population size. During this search, D. superbus was found for the first time in a meadow between the River Pededze and a forest, and on a nearby hillock. Seeds were collected at all locations for an ex situ collection.
Ex situ conservation was carried out by introducing and maintaining in vitro collections and field plantings in the National Botanic Garden (NBG) and the Botanical Garden of the University of Latvia (BG UL). As D. superbus is able to adapt to a wide range of soil conditions (i.e., nutrient availability, organic matter content and soil reaction) the conservation of this species can also be implemented in urban areas. The authors conclude by highlighting the three main preconditions for the successful recovery of D. superbus in Latvia—adequate lighting, low overgrowth of other plant species and non-destructive human activity.
Osvalde, A., Jakobsone, G., Akmane, I., Svilāns, A., Dubova, I., 2021. Dianthus superbus as a critically endangered species in Latvia: evaluation of its growth conditions and conservation possibilities. AoB PLANTS. https://doi.org/10.1093/aobpla/plab051