Great Lakes barrens, a globally rare community type, is a variant of the pine barrens community known in Wisconsin primarily from sandspits in the Apostle Islands. It was historically of limited extent, and occurred on sandspits and dunes along the Great Lakes shorelines. The small number of occurrences in Wisconsin makes it difficult to characterize the type with confidence. The groundlayer is composed mostly of lichens, fungi, grasses, sedges, ericaceous shrubs and sub-shrubs, and a limited number of flowering herbs. Dominant trees in the more open stands are pines, especially red pine (Pinus resinosa), are widely scattered, and demonstrate the limb architecture that develops under open-grown conditions, as well as wind and fire deformities. Eastern white pine (Pinus strobus) may also be present and jack pine (Pinus banksiana) is now dominant in a few areas that have high restoration potential. The understory consists of dense carpets of lichens, scattered thickets of common juniper (Juniperus communis), patches of early blueberry (Vaccinium angustifolium), huckleberry (Gaylussacia baccata), and sand cherry (Prunus pumila). Other common plants include crinkled hair grass (Deschampsia flexuosa), tickle grass (Agrostis hyemalis), false-heather (Hudsonia tomentosa), sand cress (Arabidopsis lyrata), and bearberry (Arctostaphylos uva-ursi).
The extremely xeric site conditions and periodic past wildfires have maintained this community over time. Fire scars on living pines and snags from Stockton Island in the Apostles Archipelago revealed highly variable fire frequencies, ranging from multiple fires within a five-year period to the passage of decades with no evidence of fire whatsoever (E. Epstein, personal observation 1988). Associated natural communities include Great Lakes beach, Great Lakes dune, interdunal wetland, and northern dry forest.