Name:
Juniperus horizontalis - Dasiphora fruticosa / Schizachyrium scoparium - Carex richardsonii Dwarf-shrubland
Reference:
NatureServe Biotics 2019
Description:
The creeping juniper - shrubby-cinquefoil alvar pavement shrubland type occurs in the Great Lakes region of the United States and Canada, in Ontario, Canada and in northern Michigan. Stands occur on very shallow soils (usually less than 10 cm deep) over flat dolostone outcrops (pavements). The surface of the dolostone pavement is often broken into small pieces (from 1 cm to 1 m in the longest dimension) by frost heaving, sometimes called rubble pavement. These pavements are typically very droughty in summer, except right after rainfall, when ephemeral shallow pools can form on the bedrock surface. Creeping juniper - shrubby cinquefoil alvar pavement usually occurs in a patchy landscape mosaic with other alvar communities, most commonly with little bluestem alvar grassland, tufted hairgrass wet alvar grassland, juniper alvar shrubland, and alvar nonvascular pavement. This community has at least 25% cover of dwarf-shrubs (under 0.5 m tall); the dominant shrubs are <i>Juniperus horizontalis</i>, and/or <i>Dasiphora fruticosa ssp. floribunda</i>. Other characteristic species include <i>Schizachyrium scoparium, Carex richardsonii, Carex scirpoidea, Pinus banksiana, Thuja occidentalis, Danthonia spicata, Oligoneuron album, Packera paupercula, Clinopodium arkansanum</i>, and <i>Tetraneuris herbacea</i>. This community has less than 50% cover of herbaceous plants, and less than 10% cover of trees over 5 m tall. There is often a lot of exposed dolostone bedrock pavement, but exposed bedrock is always less than 50% of the ground surface area. Much of the exposed rock surface is covered with microscopic algae (e.g., <i>Gloeocapsa alpina</i>). Mosses and lichens are common, including <i>Tortella tortuosa, Schistidium rivulare, Placynthium nigrum</i> and <i>Cetraria arenaria</i>. This community is closely related to Little Bluestem Alvar Grassland, and the two communities are frequently interspersed.
Accession Code:
urn:lsid:vegbank.org:commConcept:33999-{EB55809D-B4F9-44B8-ADC5-B4730DE9A6C3}
Plot-observations of this Community Concept:
3
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