(1808) Triphragmium ulmariae is a species of rust fungus in the family Sphaerophragmiaceae.

It causes meadowsweet rust gall,[2] which develops as a chemically induced swelling, arising from the lower surface of the meadowsweet (Filipendula ulmaria) leaves.

[3] The fungus grows in the petioles and midribs of the perennial plant meadowsweet (Filipendula ulmaria), a member of the rose family, causing swelling and distortion.

[3] The rust's spores reach the new meadowsweet plants via air movements.

The rust has a severe effect on the survival of meadowsweet seedlings.