I was photographing the flowers of a roadside Tree mallow for a mid-autumn wildflowers-in-bloom blog that will be publishing this coming Sunday when I noticed the subject of today’s blog post, this new-to-me rust, Puccinia malvacearum. Its common names, Mallow rust and Hollyhock rust, provide the perfect indication for which plants are host to this fungus.

As is typical with rusts, this species had created yellow-orange spots on the upper surface of the leaves and brownish lumpy pustules on the lower surface and on the plant’s stems. The rust would eventually reduce the plant’s vigour, leading to stunted growth and leaf loss, though, as this particular plant was growing in a location very likely to be mown regularly by council workers, the plant will probably be cut down long before it could succumb to the rust’s damage.