There are no more important plants in Gumbo Limbo Nature Center than mangroves. These trees literally hold the land together, protecting shorelines from erosion, protecting water quality and acting as a sheltered nursery for the young of many fish and other marine creatures, including some economically important game species. Follow the the boardwalk trail and you'll notice the tropical hammock giving way to a mangrove forest as you approach the Intracoastal Waterway. There are three mangroves species found in Florida: red, black and white and all three are present at Gumbo Limbo. Each species occupies a certain niche in relation to the water and land. Pictured above are red mangroves, the so-called walking trees and the species with limb-like roots that grow out into the water. Black mangroves, with there stick-like roots popping out of the muck, are the middle species, and white mangroves grow farthest inland. To underscore how important these trees are, it's illegal to cut them down or even for private landowner to trim one unless the work is done by a certified arborist. The Florida Department of Environmental Protection estimates the economic value of the state's mangroves at $7.6 billion. NEXT PHOTO.