P. vulgaris (French bean) seems essentially immune, but I get quite
dense localised infestations on P. coccinea (runner bean). What
puzzles me is why they don't spread, the way that they do with broad
beans, and to a great extent most of their other summer hosts. They
don't spread on their winter habitats, of course, but these cases
occur during summer and autumn and look far more like summer ones
than winter ones.

Has anyone got any insights?


Regards,
Nick Maclaren.