introduction - Pennsylvania Natural Heritage Program

APPENDIX ISIGNIFICANCE RANKSThe Natural Heritage Areas that have qualified for inclusion in this report are ranked according to theirsignificance as areas of importance to the biological diversity and ecological integrity of ClearfieldCounty. The four significance ranks are: Exceptional, High, Notable, and County significance. Theseranks have been used to prioritize all identified sites and suggest the relative attention that sites shouldreceive for protection.Exceptional: Sites that are of exceptional importance for the biological diversity and ecological integrityof the county or region. Sites in this category contain one or more occurrences of state or national speciesof special concern or a rare natural community type that are of a good size and extent and are in arelatively undisturbed condition. Sites of exceptional significance merit quick, strong and completeprotection.High: Sites that are of high importance for the biological diversity and ecological integrity of the countyor region. These sites contain species of special concern or natural communities that are highly ranked,and because of their size or extent, relatively undisturbed setting, or a combination of these factors, rate asareas with high potential for protecting ecological resources in the county. Sites of high significancemerit strong protection in the future.Notable: Sites that are important for the biological diversity and ecological integrity of the county orregion. Sites in this category contain occurrences of species of special concern or natural communitiesthat are either of lower rank (G and S rank) or smaller size and extent than exceptional or high rankedareas, or are compromised in quality by activity or disturbance. Sites of notable significance meritprotection within the context of their quality and degree of disturbance.County: Sites that have great potential for protecting biodiversity in the county but are not, as yet, knownto contain species of special concern or state significant natural communities. Often recognized becauseof their size, undisturbed character, or proximity to areas of known significance, these sites invite furthersurvey and investigation. In some cases, these sites could be revealed as high or exceptional sites.152