Native Plant Communities

Rockland Hammock

Community Variants: Keys Rockland , Tropical Hammock

Rockland Hammocks have subtropical climates.  They are flat lands with limestone at or near the surface.  They include local limestone solution features which provide microhabitats that add to the diversity.  The hammocks are generally mesic (moist) to dry mesic.   Fire is rare.  

The vegetative community is one that has tropical affinities and which can grow on highly calcareous substrates.  The list of species found in the canopy and subcanopy is staggering with over 150 having been reported by some authors (FNAI 2010, USFWS 2000).  The vegetation list varies with climate, exposure to salt spray (or for the keys, potential inundation from storm surger), wind, depth to limestone, etc.  Most are evergreen.  Most are not tolerant of freezes.  Epiphytes are common.  

Keys Rockland Hammock is restricted to the Florida keys.  It has limestone at or very close to the surface, and vegetation with more Caribbean affinities and fewer continental affinities than Rockland Hammocks on the mainland.

Tropical Hammock in peninsular Florida tends to have more soil over the limesone.  It has fewer species with Caribbean affinities and more species from more northern mainland locations.

Shell Mounds are sometimes included with Tropical Hammocks given that the vegetation can be similar.  However, they lack the limestone substrate.  They are anthropomorphic in origin and consist of mounds of shells that were built by indiginous people. These mounds are sometimes classified as Maritime Hammocks.

Excellent examples of Rockland Hammock occur in the Everglades National Park, Collier-Seminole State Park, Curry Hammock State Park and Windley Key Geological State Park, Lignum Vitae Key State Park, and in Miami-Dade County preserves.

References:

Bradley, K., and G. Gann. 1999. The pine rockland forests of southern Florida. The Palmetto 19:12-19. http://fnps.org/assets/pdf/palmetto/bradley_keith__george_gann_the_pine_rockland_forests_of_florida_vol_19_no_2_summer_1999.pdf.

Duever, M. J., J E Carlson, J. F. Meeder, L. C. Duever, L. H. Guderson, L. A. Riopelle, T. R. Alexander, R. L. Myers, and D. P. Spangler.  1986.  The Big Cypress National Preserve.  Research Report 8, National Audubon Society.

Florida Department of Environmental Protection. 1992. Soil and Water Relationships of Florida's Ecological Communities http://www.dep.state.fl.us/water/wetlands/delineation/docs/soil-and-water.pdf

Duever, Linda. 1984 (April). Florida's Natural Communities: Rocklands. The Palmetto 4, #2:8-11. http://fnps.org/assets/pdf/palmetto/duever_linda_conway_natural_communities_of_floridas_rocklands_vol_4_no_2_april_1984.pdf

Florida Natural Areas Inventory (FNAI). 2010. Guide to the natural communities of Florida: 2010 edition. Florida Natural Areas Inventory, Tallahassee, FL. http://fnai.org/naturalcommguide.cfm

Gann, G.D., K.A. Bradley, and S.W. Woodmansee. 2009. Floristic Inventory of South Florida Database. Institute for Regional Conservation. http://regionalconservation.org/ircs/database/database.asp

Knight, G. R., J. B. Oetting, and L. Cross.  2011.  Atlas of Florida's Natural Heritage - Biodiversity, Landscapes, Stewardship and Opportunities:  Institute of Science and Public Affairs, Florida State University, Tallahassee, FL.

Loope, L.L., D.W. Black, S. Black, and G.N. Avery. 1979. Distribution and abundance of flora in limestone rockland pine forests of southeastern Florida. South Florida Research Center, Everglades National Park, Homestead, Florida.

Myers, R.L. and J.J. Ewel (eds.). 1990. Ecosystems of Florida University of Central Florida Press: Orlando.

USDA Soil Conservation Service. 1986. 26 Ecological Communities of Florida. http://ufdc.ufl.edu/UF00000110/00001

USFWS. 2000. Multi-Species Recovery Plan for South Florida.  Tropical Hammock.  https://www.fws.gov/verobeach/MSRPPDFs/TropHammock.pdf.

Whitney, E.N., D. B. Means, A. Rudloe. 2004. Priceless Florida: Natural Ecosystems and Native Species. Pineapple Press.

Date Updated 2020-05-18 11:45:57

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Rockland Hammock, Lignum Vitae Key State Park

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Rockland Hammock, Tropical Hammock - Curry Hammock, Monroe County, by Shirley Denton.

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Rockland Hammock, Windley Key Geological State Park.  Photo by Shirley Denton.