In addition to the 104-acre Interpretive Center site in Picayune, the Crosby Arboretum maintains seven natural areas in Pearl River, Hancock, and Lamar counties. These areas comprise nearly 700 acres and are being preserved and managed for research. The natural areas were selected with diversity of vegetation types in mind. Longleaf pine forests, slash pine- hardwoods, sweetbay-tupelo-swampbay, beech-magnolia, baldcypress-tupelo, bottomland hardwoods, hillside bogs, and savannas are just some of the forest types represented.
Hillside Bog- Perhaps the most spectacular of the Crosby Arboretum natural areas, Hillside Bog consists of 70 acres in northern Hancock County. It encompasses a hillside bog, longleaf pine, sweetbay-tupelo-swampbay, and longleaf pine-scrub oak. The area is highly diverse in habitat types and species present.
Dead Tiger Creek Hammock- This 20-acre area is an example of a low, non-alluvial, hardwood swamp. This habitat type extends eastward along the Gulf Coast, but not much farther west. In addition to the hammock, marginal areas provide habitat for a variety of species including Coreopsis nudata and Macranthera flammea, both spectacular wildflowers.
Dead Tiger Creek Savanna- This 20-acre natural area includes a pine ridge, sloping bog area, and a flat savanna. Most of the holly species found in Mississippi can be found here. Two species of pitcher plants and their hybrids have been noted.
Red Bluff - Located along Catahoula Creek, Red Bluff has approximately 320 acres. It has an unusual physical setting with a clear-water stream and sandy white beaches. The area includes a diversity of habitat types including oxbow lakes, titi-lined creek banks, open sandy areas, gum swamps, and dry pine woods.
Talowah- This area contains 120 acres of longleaf pine ridges dissected by narrow belts of hardwoods along the branch bottoms. The open park-like nature of the longleaf pine is maintained by periodic burning. This results in a rich herbaceous flora including many composites and legumes.
Mill Creek-Only 20 acres in size, Mill Creek is one of the most interesting natural areas. It is classified as a mature beech-magnolia woodland. All five species of magnolia in the state are found here. Many large trees of beech, southern magnolia, swampbay, spruce pine, and yellow-poplar are present.
Steep Hollow- The area is vegetationally diverse and includes quaking bogs, longleaf pine slopes and ridges, and sweetbay-tupelo-swampbay areas. Steep Hollow is exceptionally rich in species and contains more variety than any of the other natural areas.