The researchers of the ELKH Centre for Ecological Research (CER) investigated the spread of the non-native great blanketflower in Hungary within the framework of the National Laboratory for Health Security project. The aim of the research was to evaluate the impact of the species on the local plant community and determine its invasive potential through its functional traits. Based on the results, the great blanketflower does not currently appear to be a strong ecosystem-transforming species, but there is a risk that due to climate change, the local environment in Hungary will become more suitable for it in the future, leading to strong speading and becoming invasive. Therefore, the researchers do not recommend planting blanketflower species in gardens. They also suggest surveying non-native ornamental plant populations, conducting long-term monitoring and a more detailed assessment of the traits that influence their spread. The publication presenting the results was published in the scientific journal NeoBiota.
Ornamental plants are one of the main sources of species becoming invasive. During their planting, they are introduced to new habitats where humans create favourable living conditions through irrigation and maintenance. Later, in natural habitats, they can easily occupy open niches created by human disturbances and the warming effects of climate change. The blanketflower has followed this path as well, and its ecological impacts were studied by researchers of CER along with several other new, potentially dangerous species within the recently initiated National Laboratory for Health Security project.
The great blanketflower and its relative, the Indian blanket, along with their hybrid, are globally planted ornamental plant species. Reports have already been made in several countries about the great blanketflower escaping from gardens and naturalizing in various new habitats, but its invasive behavior has been relatively unknown until now. However, it seems that in the past few decades, this species has found suitable habitats in Hungary and from a naturalized species it has become invasive in several locations. "Our aim was to map the distribution of the great blanketflower in Hungary, evaluate its impact on the local plant community, and determine the species' invasive potential through its functional traits," summarized Gabriella Süle, Phd, assistant research fellow at CER.
Based on the distribution data collected here, the great blanketflower occurs in Hungary mainly as casual escapes yet. This species, which blooms profusely throughout the year and is extremely colorful, requires little to no care. Therefore, owners allow it to spread, and we can often see it occupying more and more space in front of gardens. However, it became naturalized in recent years, and invasive populations have also been found in significant numbers within the country. The species is mainly observed near gardens and disturbed habitats, but it has also appeared in natural and semi-natural grasslands. It successfully spreads in disturbed, species-poor, sandy, open habitats. Its spread affects the composition of the local plant community, reducing, for example, the species richness of local plants. Based on its functional traits, its well germination capacity, extremely long flowering period, the large absorbing and adhering surface provided by its roots, and its spread by grazing animals' fur, mainly sheep, can promote its invasive spread. Currently, the great blanketflower does not appear to be a strong ecosystem-transforming species, but more attention needs to be paid to it because there is a risk that the local environment in Hungary will become increasingly suitable for it due to drier weather caused by climate change, leading to strong spread and becoming invasive, primarily in sandy soils.
"Due to all of these, we do not recommend planting blanketflower species in gardens, as they can easily escape and establish in natural plant communities. Furthermore, we suggest considering banning their distribution in seed mixes. To control invasive populations in natural habitats, there is a need to develop an effective eradication method," emphasized Gabriella Süle, Phd.
Assessing the great blanketflower and similar non-native ornamental plant populations, conducting long-term monitoring, and performing a more detailed evaluation of the traits influencing their spread would be important in order to prevent the escape of species planted in gardens into the natural habitats on time.
Assessing and managing the ecological, economic, and societal threats posed by invasive species similar to the great blanketflower is one of the focuses of the Division of Invasion Biology within the National Laboratory for Health Security project. The research is being carried out within the framework of the Széchenyi Plan Plus program with the support of the RRF-2.3.1-21-2022-00006 project.