NVC community M4 (Carex rostrata - Sphagnum recurvum mire) is one of the mire communities in the British National Vegetation Classification system.
It is a localised community of northern and western Britain.
There are no subcommunities.
The following constant species are found in this community: Two rare species are associated with the community: This community is found in Cornwall and in various locations in Wales, northern England and Scotland.