This is a white blister-rust fungus that cause galls on Goat's-beard and Salsify (Tragopogon).  Whitish crusty pustules are formed on the leaves, and the plant is sometimes distorted and deformed.

host

Photograph the blister-rust on the host plant; ensure you have noted the host species in your comments

On Goat's-beard and Salsify plants.

This is part of the Pustula obtusata sensu lato species complex that affects a wide range of hosts in the Asteraceae, including Ragworts (Senecio and Jacobaea).