|                    Brittle maidenhair
                      |  
              
                |                    Adiantum tenerum  
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                |                    Pteridaceae 
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                 Landscape Uses:
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                 A delicate accent fern on exposed moist limestone in rock gardens and on the banks of water features such as natural pools. Identified by Fairchild Tropical Botanic Garden as a native that does especially well in shade in this brochure. | 
               
                Ecological Restoration Notes:  | 
               
              
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                 Limited to exposed moist limestone in rockland hammocks with constantly high humidity.  The lowered water table in Miami-Dade County makes this a difficult species to incorporate into restoration projects. | 
               
              
                | Availability: | 
               
              
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                 Grown by enthusiasts. | 
               
              
                | Description: | 
               
              
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                 Medium herbaceous fern with delicate leaflets (pinnae). | 
               
              
                | Height: | 
               
              
                |   | 
                 About 12-18 inches in height.  About as broad as tall. | 
               
              
                | Growth Rate: | 
               
              
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                 Moderate. | 
               
              
                | Range: | 
               
              
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                 Miami-Dade County; disjunct in central and northern peninsular Florida; West Indies, Central America and Venezuela. | 
               
              
                | Habitats: | 
               
              
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                 On moist limestone in rockland hammocks. | 
               
              
                | Soils: | 
               
              
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                 Moist limestone rock, with or without an accumulation of humusy material. | 
               
              
                | Nutritional Requirements: | 
               
              
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                 Moderate; can grow in nutrient poor soils, but needs some organic content to thrive. | 
               
              
                | Salt Water Tolerance: | 
               
              
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                 Low; does not tolerate flooding by salt or brackish water. | 
               
              
                | Salt Wind Tolerance: | 
               
              
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                 Low; salt wind may burn the leaves. | 
               
              
                | Drought Tolerance: | 
               
              
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                 Low; requires moist substrate and high humidity and is intolerant of long periods of drought. | 
               
              
                | Light Requirements: | 
               
              
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                 Light shade. | 
               
              
                | Flower Color: | 
               
              
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                 N/A. | 
               
              
                | Flower Characteristics: | 
               
              
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                 There are no flowers; the plants reproduce by spores. | 
               
              
                | Flowering Season: | 
               
              
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                 All year. | 
               
              
                | Fruit: | 
               
              
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                 Inconspicuous spores. | 
               
              
                | Wildlife and Ecology: | 
               
              
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                  | 
               
                     
                | Horticultural Notes: | 
               
              
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                 Can be grown from spores. | 
               
              
                | Comments: | 
               
              
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                 In the right situations, this rock-loving fern will recruit readily in the garden.  It is listed as endangered by the state of Florida. | 
               
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                    George D. Gann in habitat, Dominican Republic, 2011
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                    George D. Gann in habitat, Everglades National Park, Florida, 2005
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