Eva Luigas: Assess Invasive Species by Their Impact on Nature, Not Beauty
Gardener Eva Luigas calls for evaluating alien species based on their ecological impact rather than appearance. She highlights lupine, rugosa rose, and Sakhalin knotweed as problematic species endangering local ecosystems.
Amateur gardener Eva Luigas stresses that when assessing alien species, one should be guided by their impact on nature, not personal preference. She advises trusting specialists' conclusions and looking at how the species affects the ecological balance.
Lupine Issues
According to Luigas, the much-discussed lupine is problematic primarily because it spreads quickly in the wild and changes growing conditions. Lupine is a legume that fixes nitrogen, enriching the soil. If the plant escapes from a garden into nature, such changes can harm native species accustomed to nutrient-poor conditions.
Impact on Wildlife
Luigas notes that the impact extends beyond plants. If some species disappear from a habitat, it also affects insects and birds. Therefore, she strongly recommends removing alien species: "If someone sees alien species being removed by rather harsh methods, it doesn't mean the person has gone mad – it is necessary."
Rugosa Rose
As another problematic alien species, Luigas mentioned the rugosa rose, which has spread widely in many coastal areas of Estonia. According to her, the plant spreads via seeds and root suckers, able to occupy large territories. In the wild, the rugosa rose displaces native coastal plants.
Sakhalin Knotweed
Speaking of alien species, Luigas also cited Sakhalin knotweed, which she has fought for years. The plant spreads very persistently, and even uprooting may not yield quick results. Because of Sakhalin knotweed, she had to remove lilacs planted by her grandparents. Luigas emphasized that dug-up plant parts should not be composted or taken to the forest.
Human Role
When asked whether people themselves are behind the spread of many alien species, Luigas replied that gardeners cannot always be blamed, but often the problem started with ornamental plant cultivation. According to her, over centuries new plants have been brought from around the world to ornamental and botanical gardens, and in most cases they cause no problems. Danger arises when a species gets out of control.
