Biological Control
The Slender Thistle Rust Fungus Puccinia cardui-pycnocephali has been in Australia since the early 1900s but new strains were released in 1995. They proved virulent especially in wet summers. See Faithfull et. al. 1998.
The Slender Thistle Rust Fungus Puccinia cardui-pycnocephali has been in Australia since the early 1900s but new strains were released in 1995. They proved virulent especially in wet summers. See Faithfull et. al. 1998.