Oreojuncus

{{short description|Genus of Juncaceae plants}}

{{Automatic taxobox

|image=Juncus trifidus-Kaernten-2008-Thomas Huntke.jpg

|image_caption=Oreojuncus trifidus

|display_parents=2

|taxon=Oreojuncus

|authority=Záv.Drábk. & KirschnerPreslia 85: 498 (2013)

|subdivision_ranks=Species

|subdivision=See text

}}

Oreojuncus is a small genus of flowering plants in the rush family Juncaceae, found in the eastern United States, eastern Canada, Greenland, Iceland, the Faroes, most of Europe, northern Russia, western Siberia and the Altai. Their chromosome number is 2n=30 (x=15), whereas Juncus, from which they were split, has x=20.{{cite journal |title=A Survey of Karyological Phenomena in the Juncaceae with Emphasis on Chromosome Number Variation and Evolution |year=2013 |last1=Záveská Drábková |first1=Lenka |journal=The Botanical Review |volume=79 |issue=3 |pages=401–446 |doi=10.1007/s12229-013-9127-6 |bibcode=2013BotRv..79..401Z |s2cid=18620862 }}