Il metodo più efficace per estirparle? Tagliarle raso suolo con una motosega. L’espansione della palma di Fortune (Trachycarpus fortunei), chiamata anche palma ticinese perché onnipresente nei giardini del cantone, preoccupa l’Istituto federale di ricerca per la foresta, la neve e il paesaggio (WSL) che ora propone misure radicali contro la neofita invasiva.
Il problema, sottolinea il WSL, è la diffusione nei boschi ticinesi tanto che “sembra di essere ai tropici”. Non si tratta solo di un problema estetico, i ricercatori hanno infatti rilevato che nei siti ricchi di palme ci sono molte meno specie vegetali. Ciò comporta anche un indebolimento della funzione protettiva delle foreste contro i pericoli naturali.
Il problema non è ovviamente in riva ai laghi
Per limitarne la diffusione vale la rimozione di fiori e frutti dalle piante. Anche se una loro completa eliminazione nei boschi non è realistica, gli scienziati ne raccomandano il taglio radicale nelle aree di valore ecologico.
Palme invasive
Il Quotidiano 29.12.2018, 19:00
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