Pampas grass (Cortaderia selloana), a plant native to the Pampas in Argentina and Chile, was used decoratively in gardens and interiors for decades, which contributed to its silent dispersal across Portugal. Currently, despite being on the National Invasive Species List since 2019, it is recorded in 208 of Portugal's 278 municipalities, making it one of the ten most widely distributed invasive plants in the country.
Hélia Marchante, a professor at the School of Agriculture of the Polytechnic University of Coimbra and partner of the LIFE COOP Cortaderia project (2023-2028), warns that "we are not facing a future threat" but rather an invasion already established and advancing rapidly. The plant affects both disturbed environments and natural habitats of high conservation value, including dunes, estuaries, riverbanks, and grasslands. When it forms dense patches, it reduces the space, light, and resources available to native plant species, also harming the animals that depend on them and human health, being considered an allergen.
The country's interior, from north to south, has lower presence of pampas grass, with the invasion mainly concentrated on the coast and peri-urban areas of the North and Centre. It is precisely in these locations with lower presence that specialists consider intervention urgent, as with fewer resources isolated plants can be eliminated more successfully and future invasions prevented. Currently in bloom, each female plant produces millions of wind-dispersed seeds, allowing accelerated expansion. Since 2023, there has been a proposal for a National Action Plan for the control of the species, submitted to the Institute for Nature Conservation and Forests,
