Natural communities are composed of groups of plant and animal species that regularly or often occur in association with each other in certain landscapes or physical environments. Nature is seldom divided into discrete units and is characteristically composed of a continuous mosaic of natural communities. The factors that help to define a particular community (i.e. - associated vegetation, soil, substrate, hydrology, topography, climate, fire history) usually exist along gradients, and therefore every occurrence of a natural community will be unique in some way. In developing our classification of the Natural Communities of Louisiana, levels of distinctiveness are defined according to the physical and biotic factors that occur repetitively at various locations.
A system for classifying natural communities is a prerequisite for an inventory of a region's natural resources. Both the classification system and inventory are essential for a complete understanding of the natural resources of that region, and also provide the framework for determining the area's protection priorities and research needs. Protecting natural communities preserves the ecological functions of the area while also providing the added benefit of safeguarding both the rare and common species occurring within that community type.
Natural community data for this classification was initially gathered from secondary sources such as previously existing inventories, scientific literature, and consultation with experts in the field. The resulting classification was then refined through data collected from scores of field surveys conducted throughout Louisiana since 1984 by LNHP staff. While this database is quite extensive, there are still many natural areas in Louisiana that have not been surveyed. New community records are continuously being added to the database, and current records are updated as new information becomes available. Therefore, our natural community classification is a dynamic system and individual categories may be added, preexisting ones may be subdivided or merged, or deletions may occur as additional information comes to light, and updated approximations will be periodically produced.
In the Natural Heritage methodology, classification of natural communities is followed by a continuous inventory for exemplary occurrences of each community type. The communities are prioritized through a ranking system, and strategies for protection of each particular community type are then formulated. Exemplary natural communities include all or any examples of rare types (such as LA coastal prairies) and also the highest quality examples of more common community types (such as bottomland hardwood forests). Typical exemplary forested communities have high species diversity, multiple age classes among the dominant tree species, presence of natural regeneration, standing dead snags and fallen woody debris in various stages of decomposition, an intact and fully functioning soil component, and little evidence of human disturbance.
According to LNHP's current natural community classification, Louisiana has 66 community types within the 6 ecoregions of Louisiana. Some community types are widespread across the state and while others are localized or restricted. Although much of Louisiana is still covered in native vegetation, undisturbed examples of all natural communities are rare, and many are extremely scarce. Essentially no virgin habitat remains. Threats to Louisiana communities exist from coastal erosion and associated coastal disturbance factors, urban expansion, residential and commercial development, land disturbance operations, introduction of exotic species, and many other human and some natural disturbance factors. LHNP has been a beneficial force in helping to identify areas in Louisiana that warrant protection, and through the work of the state, conservation organizations, and concerned private landowners, this has resulted in conservation of places such as the Lake Ramsey Wildlife Management Area, Copenhagen Hills, and Tunica Hills Wildlife Management Area to name a few. Forest landowners and land managers who wish to maintain and enhance the natural communities and associated species in their care can follow recommendations outlined in LNHP's Guidelines for Practicing Forest Environmental Enhancement in Louisiana. Any questions, concerns, information requests concerning LA natural communities, or comments regarding our classification system are welcomed and should be directed to: