It was long considered that Sporadanthus plants in the North Island were the same species as Sporadanthus traversii, which is native to Chatham Island, east of the New Zealand mainland.

[2] S. ferrugineus grows in acidic, ombrotrophic, restiad-dominated raised bogs.

Draining of such bogs for farming in the northern North Island has greatly reduced their extent.

S. ferrugineus is now mainly found at the peat domes of Kopuatai and Torehape on the Hauraki Plains and Moanatuatua Swamp in the Waikato basin.

[3] Under the New Zealand Threat Classification System, it is classified as "At Risk - Relict" (It has both a restricted range, and its documented decline shows it as now occupying less than 10% of its former range, but the population is considered stable.