page_title: Geography and ecology of the Everglades
section_title: Tropical hardwood hammock
hierarchical_section_title: Geography and ecology of the Everglades / Ecosystem characteristics / Tropical hardwood hammock
caption_attribution_description: English: Tropical hardwood hammock on Everglades National Park Mahogany Hammock Trail
context_page_description: The geography and ecology of the Everglades involve the complex elements affecting the natural environment throughout the southern region of the U.S. state of Florida. Before drainage, the Everglades were an interwoven mesh of marshes and prairies covering 4,000 square miles. The Everglades is simultaneously a vast watershed that has historically extended from Lake Okeechobee 100 miles south to Florida Bay, and many interconnected ecosystems within a geographic boundary. It is such a unique meeting of water, land, and climate that the use of either singular or plural to refer to the Everglades is appropriate. When Marjory Stoneman Douglas wrote her definitive description of the region in 1947, she used the metaphor "River of Grass" to explain the blending of water and plant life.
  Although sawgrass and sloughs are the enduring geographical icons of the Everglades, other ecosystems are just as vital, and the borders marking them are subtle or nonexistent. Pinelands and tropical hardwood hammocks are located throughout the sloughs; the trees, rooted in soil inches above the peat, marl, or water, support a variety of wildlife.
context_section_description: Islands of trees featuring dense temperate or tropical trees are called tropical hardwood hammocks. They may rise between 1 and 3 feet (0.30 and 0.91 m) above water level in freshwater sloughs, sawgrass prairies, or pineland. These islands illustrate the difficulty of characterizing the climate of the Everglades as tropical or subtropical. Hammocks in the northern portion of the Everglades consist of more temperate plant species, but closer to Florida Bay the trees are tropical and smaller shrubs are more prevalent. Tropical trees like the West Indian mahogany (Swietenia mahagoni) were probably spread by birds carrying seeds from the West Indies.
  These hammocks form on slightly elevated areas unharmed by deep peat fires or limestone plateaus rising several inches above the surrounding peat.  Hardwood hammocks exhibit a mixture of subtropical and hardwood trees that grow in very dense clumps, such as southern live oak (Quercus virginiana), gumbo limbo (Bursera simaruba), royal palm (Roystonea), and willow bustic (Dipholis salicifolia). Near the bases of hammocks sharp saw palmettos (Serenoa repens) flourish, making the hammocks very difficult to penetrate. Water in sloughs flow around the islands creating moats. Though some ecosystems are maintained and promoted by fire, hammocks may take decades or centuries to recover; the moats are therefore essential for protection. Islands vary in size, but most range between 1 and 10 acres (0.40 and 4.05 ha); the water slowly flowing around them limits their size and gives them a teardrop appearance from above. The height of the trees is limited by factors such as frost, lightning, and wind: the majority of trees in hammocks grow no higher than 55 feet (17 m).
  Florida strangler figs (Ficus aurea) are common in hammocks, and find particular ease in rooting at the heads of cabbage palms (Sabal palmetto). After taking root into the ground, they build complex frameworks around the host tree, eventually squeezing out light and nutrients, and essentially taking its place. A variety of invertebrates including beetles, ants, spiders, and tree snails support a food chain that includes frogs, owls and other birds of prey, snakes, rodents, bobcats, and raccoons. There are more than 50 varieties of tree snails in the Everglades; the color patterns and designs unique to single islands may be a result of the isolation of certain hammocks.
  Tropical hardwood hammocks in the Everglades have been harvested for lumber, particularly by shipbuilders seeking West Indian mahogany and black ironwood (Krugiodendron ferreum). The largest and most mature of these trees had been removed by the late 18th century. Seminoles made their villages in hammocks in the late 19th and early 20th centuries; they lived in groups of chickees numbering half a dozen, with one central chickee for cooking and another for eating. Dugout canoes, cookware, stills, and sewing machines may still be found in remote locations.
caption: In a tropical hardwood hammock, plants are very dense and diverse.
exif: {"Image ImageWidth": "3648", "Image ImageLength": "2736", "Image BitsPerSample": "[8, 8, 8]", "Image PhotometricInterpretation": "2", "Image Make": "Canon", "Image Model": "Canon PowerShot S95", "Image Orientation": "Horizontal (normal)", "Image SamplesPerPixel": "3", "Image XResolution": "180", "Image YResolution": "180", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop CS5 Windows", "Image DateTime": "2012:01:16 08:35:02", "Image YCbCrPositioning": "Co-sited", "Image ExifOffset": "292", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "1246", "Thumbnail JPEGInterchangeFormatLength": "8811", "EXIF ExposureTime": "1/200", "EXIF FNumber": "4", "EXIF ISOSpeedRatings": "80", "EXIF SensitivityType": "Standard Output Sensitivity and Recommended Exposure Index", "EXIF ExifVersion": "0230", "EXIF DateTimeOriginal": "2012:01:12 16:03:42", "EXIF DateTimeDigitized": "2012:01:12 16:03:42", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "3", "EXIF ShutterSpeedValue": "245/32", "EXIF ApertureValue": "4", "EXIF ExposureBiasValue": "-1", "EXIF MaxApertureValue": "2", "EXIF SubjectDistance": "967/100", "EXIF MeteringMode": "Pattern", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "6", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "3648", "EXIF ExifImageLength": "2736", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "Interoperability RelatedImageWidth": "3648", "Interoperability RelatedImageLength": "2736", "EXIF InteroperabilityOffset": "1096", "EXIF FocalPlaneXResolution": "912000/73", "EXIF FocalPlaneYResolution": "912000/73", "EXIF FocalPlaneResolutionUnit": "2", "EXIF SensingMethod": "One-chip color area", "EXIF FileSource": "Digital Camera", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Manual Exposure", "EXIF WhiteBalance": "Manual", "EXIF DigitalZoomRatio": "1", "EXIF SceneCaptureType": "Standard"}