Eastern Red-cedar Thicket

Definition

Detailed Community Description from Ecological Landscapes of Wisconsin

General natural community overview

Curtis (1959) described the eastern red-cedar thicket (cedar glade) community as a type of savanna. Most cedar glades occur on steep, dry sandstone, quartzite, rhyolite, or dolomite bluffs. The dominant tree is eastern red cedar (Juniperus virginiana), which may occur as scattered trees or shrubs, or, in thickets, interspersed with prairie-like openings. Red maple (Acer rubrum), paper birch (Betula papyrifera) and black and bur oaks (Quercus velutina and Q. macrocarpa) may also be present. Apart from rocky bluffs, cedar glade may also occur on very dry, gravelly slopes on south- or west-facing morainal ridges, or on coarse-textured sandy terraces along major rivers in western Wisconsin.

Today's dense "cedar thickets" are usually, if not always, the result of fire suppression on dry prairies. Prior to European settlement cedar glades may have occurred only where extensive cliffs, rivers, or lakes served as firebreaks. Common herbs include native bluestem and grama grasses (Andropogon spp. and Bouteloua spp.), prickly-pear cactus (Opuntia macrorhiza), flowering spurge (Euphorbia corollata), stiff sandwort (Minuartia michauxii), and gray goldenrod (Solidago nemoralis). The associated flora strongly resembles those of the dry prairie and sand prairie communities, with elements of dry cliff, oak barrens, and oak openings also present.

Rare animals

Species of Greatest Conservation Need

The following Species of Greatest Conservation Need are listed according to their level of association with the Eastern Red-cedar Thicket natural community type, based on the findings in Wisconsin's 2015 Wildlife Action Plan.

Scores: 3 = high association, 2 = moderate association, and 1 = low association. See the key to association scores for complete definitions.

Please see Section 2. Approach and Methods of the Wildlife Action Plan to learn how this information was developed.

Rare plants

The Natural Heritage Inventory has developed scores indicating the degree to which each of Wisconsin's rare plant species is associated with a particular natural community or ecological landscape. This information is similar to that found in the Wildlife Action Plan for animals. As this is a work in progress, we welcome your suggestions and feedback.

Landscapes

The following Ecological Landscapes have the best opportunities to manage for Eastern Red-cedar Thicket, based on the Ecological Landscapes of Wisconsin Handbook.

Major (3 on map)
A major opportunity for sustaining the natural community in the Ecological Landscape exists, either because many significant occurrences of the natural community have been recorded in the landscape or major restoration activities are likely to be successful maintaining the community's composition, structure, and ecological function over a longer period of time.

Important (2 on map)
Although the natural community does not occur extensively or commonly in the Ecological Landscape, one to several occurrences do occur and are important in sustaining the community in the state. In some cases, important opportunities may exist because the natural community may be restricted to just one or a few Ecological Landscapes within the state and there may be a lack of opportunities elsewhere.

Present (1 on map)
The natural community occurs in the Ecological Landscape, but better management opportunities appear to exist in other parts of the state.

Threats/Actions

What are conservation actions?

Conservation actions respond to issues or threats, which adversely affect species of greatest conservation need (SGCN) or their habitats. Besides actions such as restoring wetlands or planting resilient tree species in northern communities, research, surveys and monitoring are also among conservation actions described in the WWAP because lack of information can threaten our ability to successfully preserve and care for natural resources.

Threats/issues and conservations actions for natural communities

Considerations

The following are additional considerations for Eastern Red-cedar Thicket in Ecological Landscapes with opportunities for protection, restoration, and/or management. For more information, see the Wildlife Action Plan.

Northern Lake Michigan Coastal

Areas of cedar glade with eastern red cedar as the dominant tree species do occur in this Ecological Landscape, but they are not very prevalent. A variant of this community that is dominated by northern white cedar is more common in this landscape, especially in Door County. Northern white cedar glades are associated with areas where dolomite bedrock is exposed or thinly covered by soil. Deer browse is impacting the regeneration of northern white cedar and threatens the longterm persistence of this community type. Northern white cedar glades often intergrade with other communities associated with calcareous substrate such as alvar, boreal rich fen, dry cliff, and moist cliff. Management for northern white cedar glades should occur within the context of these larger community complexes.

Southeast Glacial Plains

This type is found on gravelly glacial moraines, where waterbodies, wetlands, or other features historically offered some protection from fire. Examples of this type in this Ecological Landscape can be found in the Southern Unit of the Kettle Moraine State Forest, Muralt Prairie State Natural Area (Green County), and at a few locations along the Niagara Escarpment. Cedar glade communities should be maintained where ecologically appropriate, and where this goal does not conflict with important opportunities to manage for open grasslands.

Western Coulee and Ridges

This Ecological Landscape has the best opportunity for maintaining this community type, especially along the steep bluffs of the Wisconsin, Chippewa, Black, and Mississippi Rivers, and locally, along some of the sandy terraces flanking those rivers. Occurrences of this type are found at Blue River Sand Prairie State Natural Area (Iowa County), North Bend Bottoms State Wildlife Area (La Crosse County), Badger Army Ammunition Plant (Sauk County), Devil's Lake State Park (Sauk County), and Brady's Bluff State Natural Area (Trempealeau County).

Western Prairie

Limited areas of cedar glade occur on steep bluffs along the St. Croix, Apple, and Kinnickinnic Rivers. This type needs additional evaluation in this Ecological Landscape.

Photos

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Eastern Red-cedar Thicket Photos

Note: photos are provided to illustrate various examples of natural community types. A single photograph cannot represent the range of variability inherent in a given community type. Some of these photos explicitly illustrate unusual and distinctive community variants. The community photo galleries are a work in progress that we will expand and improve in the future.