Calcareous pavement barrens are threatened by development (e.g., conversion to agricultural uses such as pastureland, residential, industrial), either directly within the community or in the surrounding landscape. Other threats include habitat alteration (e.g., road crossings, intensive cedar logging, mining) and relatively minor recreational overuse (e.g., ATVs, trampling by visitors, trash dumping). Deer overbrowsing may be a threat at a few sites. Several calcareous pavement barrens are threatened by invasive species, such as black swallow-wort (Cynanchum louiseae), Morrow's honeysuckle (Lonicera morrowii), and buckthorn (Rhamnus cathartica).

Increase and/or maintain the size of existing calcareous pavement barrens by increasing patch size where appropriate, by "softening" the abrupt forest edges by maintaining a native shrub transition zone. Improve the condition of existing calcareous pavement barrens by reducing and/or eliminating invasive species, such as black swallow-wort (Cynanchum louiseae), Morrow's honeysuckle (Lonicera morrowii), and buckthorn (Rhamnus cathartica). Improve barrens by minimizing trail network and clearly marking existing trails, and developing and implementing a prescribed burn plan at appropriate sites. Improve the landscape context of the barrens by encouraging surrounding landowners to establish natural buffers and restore natural corridors to other larger natural landscape blocks.

Soils are very thin or lacking in and around this community and the effect of clearing and construction on soil retention and erosion must be considered during any development activities. Similarly, these pavements have wide cracks and fissures and any soil enrichment contamination (e.g., from septic leach fields and fertilized lawns) may rapidly alter the water quality of underlying aquifers as well as altering the barrens community structure and function (White 1977).

Survey for occurrences statewide to advance documentation and classification of calcareous pavement barrens. Continue searching for large sites in excellent to good condition (A- to AB-ranked). Periodic inventory of the calcareous pavement barrens is needed, especially in the alvar areas in Jefferson County, in order to keep occurrence data current.

Research the composition of calcareous pavement barrens statewide in order to characterize variations (e.g., alvar vs. non-alvar types). Collect sufficient plot data to support the recognition of the more restricted "alvar pavement-grassland" and distinguish it from the broader concept of calcareous pavement barrens.

Northern Harrier (Circus cyaneus) Common Moonwort (Botrychium lunaria) Clay-colored Sparrow (Spizella pallida) Karner Blue (Plebejus melissa samuelis) Purple Rock-cress (Boechera grahamii) Side-oats Grama (Bouteloua curtipendula var. curtipendula) Cork Elm (Ulmus thomasii)

Alpine Willow-herb (Epilobium hornemannii ssp. hornemannii) Rock-cress (Draba arabisans) Golden Corydalis (Corydalis aurea) Wiry Panic Grass (Panicum flexile) Lindley's Aster (Symphyotrichum ciliolatum) Imperial Moth (Eacles imperialis imperialis) Mountain Death Camas (Anticlea elegans ssp. glaucus)