Areas invaded by Opuntia stricta and O. ficus-indica divided into N2000 habitats (sensu Habitats Directive, 92/43/EEC) and density classes. Density classes according to a logarithmic scale with 5 intervals: class 1 with 1–10 individuals per hectare, class 2 with 10–100 individuals per hectare (50 average individuals estimated), class 3 with 100–1000 individuals per hectare (550 average individuals estimated), class 4 with 1000–4000 individuals per hectare (2500 average individuals estimated), and class 5 with >4000 individuals per hectare (10000 average individuals estimated).

 
 
  Part of: Misuri A, Mugnai M, Giunti M, Dell’Olmo L, Lazzaro L (2024) Invasive alien plants at Capraia Island (Italy): distribution and threats to Natura 2000 habitats. Plant Sociology 61(1): 31-44. https://doi.org/10.3897/pls2024611/02