This community is widespread throughout upstate New York north of the North Atlantic Coast Ecoregion. It is concentrated in the mountainous areas of upstate New York. Rocky headwater stream communities are likely to be represented by different variants corresponding to major watersheds and/or ecoregions.

The broadly-defined community may be worldwide. Examples with the greatest biotic affinities to New York occurrences are suspected to span north to southern Canada, west to Minnesota, southwest to Indiana and Tennessee, and southeast to Georgia.