Buck Island Ranch, like many Florida ranches, contains a combination of improved pasture (Fertilized, Bahia grass), unimproved or semi-native pastures (unfertilized, a mixture of native and exotic grasses) and native rangeland. Because many ranches contain substantial native areas, they are extremely important for increasing and maintaining the biodiversity of the Florida landscape. At Archbold, we have made the institutional commitment to not intensify any of our semi-native and native rangeland because of their biodiversity significance.
Semi-native Pasture: The 4,500 acres of semi-native pasture ringing Buck Island Ranch are low-lying and wet, and were wetter still before regional and local draining in the 1940s-1970s. We use them for grazing primarily in the winter dry season. Unlike upland improved pastures, these semi-native prairies have never undergone heavy management. No one has fertilized or planted them, and they have many fewer ditches than the uplands. These pastures still contain many native wet prairie plant species, including Bluestem Grass (Andropogon spp.,) Redroot (Lachnanthes caroliana) Slender Flattop Goldenrod (Euthamia minor,) and Meadow Beauty (Rhexia spp.) Our East Marsh North Wetland Reserve Program site even includes a remnant of rare calcareous wet prairie, home to high densities of Tall Three-awn (Aristida patula) and Purple Muhly (Muhlenbergia sericea).
Improved Pasture: In the 1950s and 1960s, the Durrance family plowed and planted these pastures with exotic forage species, primarily Argentine Bahia Grass (Paspalum notatum). Managers in the decades prior to the establishment of BIR also ditched these pastures heavily, and applied phosphorous compounds until IFAS determined the practice unnecessary in 1987. We still fertilize with nitrogen compounds as necessary. More than half the ranch, the central 5,500 acre high ground, was improved. Before improvement, this area would have been dry palmetto prairie and savannah. While these pastures represent a much more altered environment than semi-native ones, they still provide important habitat for many native species, including the Crested Cara Cara (Caracara cheriway), Burrowing Owl (Athene cunicularia) and the Eastern Meadowlark (Sturnella magna).
Oak and Palm Hammock: The ranch has patches of Cabbage Palm (Sabal palmetto) and Live Oak (Quercus spp.) trees called hammocks, a Seminole Indian word meaning ‘shady place’. Our largest hammocks are a mile long and 100ft. wide. Hammocks naturally occur on high ground, and would have been islands in a vast wetland before the massive regional draining of the late 1940s-1960s. Archeological evidence demonstrates that the Seminoles canoed to these islands and hunted animals like White-tailed Deer (Odocoileus virginianus) that took refuge there, hence the name Buck Island Ranch. These hammocks still house deer and a variety of other animals, such as Florida Black Bear (Ursus americanus floridanus), and Eastern Diamondback Rattlesnake (Crotalus adamanteus.) Our East Marsh Wetland Reserve Program site includes remnants of wet savanna dominated by Baker’s Cordgrass (Spartina bakeri) or Sawgrass (Cladium jamaciense) with Cabbage Palm, as once would have typified this Indian Prairie region.
Wetland Reserve Program Marshes: BIR has two large wetland sites, totaling 750 acres, in the US EPA’s Wetland Reserve Program. The East Marsh North site includes a variety of largely native plant communities, including wet savanna, calcareous wet prairie, and shallow marshes dominated by Broomsedge bluestem (Andropogon virginicus), Egyptian Panicgrass (Paspalidium geminatum) and Turkey Tangle Fogfruit (Phyla nodiflora). The larger, much more disturbed West 770 Marsh site was once a vast swamp dominated by Sweet Bay (Magnolia virginiana) but only a few trees in a shallow marsh remain.
Seasonal Wetlands: BIR has about 600 small seasonal wetlands, most no more than 1.5 acres in size, which fill during the rainy season when groundwater levels are high. Our research shows that wetlands in semi-native pastures tend to have correspondingly more native and perennial species, compared to more exotic and annual species in wetlands in improved pastures. Our many common native wetland plant species include Lance-leaved Arrowhead (Sagittaria lancifolia), Common Rush (Juncus effusus), Maidencane (Panicum hemitomon) and Pickerelweed (Pontedaria cordata). Animals supported by these wetlands include Sandhill Cranes (Grus canadensis), Wood Storks (Mycteria americana), American Green Tree Frog (Hyla cinerea), and the Everglades Pygmy Sunfish (Elassoma evergladei). We are currently researching how water retention affects plant and animal communities in some of these wetlands.
Harney Pond Canal: This canal, cut 20’ deep and 100’ wide to Lake Okeechobee by the 1960s, curves around the western half of the ranch. Without this drainage, during the wet season, our semi-native pastures would be wetland, with a lake in the lowest portion to the south. In the dry season, we sometimes pump water into our pastures from Harney Pond Canal. The Canal supports a variety of fish, birds, and other wildlife, including the Glossy Ibis (Plegadis falcinellus), Florida Gar (Lepisosteus platyrhincus) and alligators (Alligator mississippiensis). The Ranch contains a few other areas of open water, like the artificial pond by the ranch buildings and in some of the larger ditches and wetlands, which house similar species.
Small Ditches: BIR has 500 miles of smaller ditches, most just a few feet wide and a few inches deep, but a few 20’ wide and several feet deep. These ditches tend to become choked with vegetation, including Common Water Hyacinth (Eichhornia crassipes), Water Lettuce (Pistia stratiotes), and Umbrella Sedges (Cyperus spp.) This plant community helps maintain water quality. Ditch denizens include the Anhinga (Anhinga anhinga), Green Heron (Butorides striatus), North American River Otter (Lontra canadensis) and the Peninsula Cooter (Pseudemys peninsularis).