Often growing far above the ground, "air plants" (or epiphytes) defy many of our common perceptions about plants. The majority use their roots only for attachment in the crowns of larger, usually woody plants-or to objects such as rocks and buildings-and derive moisture and nutrients from the atmosphere and by collecting falling debris. Only the mistletoes are true parasites. Epiphytes are not anomalies and there are approximately 28,000 species-about 10 percent of the higher or vascular plants-that grow this way. Many popular houseplants, including numerous aroids, bromeliads, ferns, and orchids, rank among the most familiar examples. In Air Plants, David H. Benzing takes a reader on a tour of the many taxonomic groups to which the epiphytes belong and explains in nontechnical language the anatomical and physiological adaptations that allow these plants to conserve water, thrive without the benefit of soil, and engage in unusual relationships with animals such as frogs and ants.
Benzing's comprehensive account covers topics including ecology, evolution, photosynthesis and water relations, mineral nutrition, reproduction, and the nature of the forest canopy as habitat for the free-living and parasitic epiphytes. It also pays special attention to important phenomena such as adaptive trade-offs and leaf economics. Drawing on the author's deep experience with epiphytes and the latest scientific research, this book is accessible to readers unfamiliar with technical botany; it features a lavish illustration program, references, a glossary, and tables.
David H. Benzing is Professor of Biology Emeritus at Oberlin College and the Jessie B. Cox Chair in Tropical Biology at Marie Selby Botanical Gardens. He is the author of Bromeliaceae: Profile of an Adaptive Radiation, Vascular Epiphytes: General Biology and Associated Biota, and The Biology of the Bromeliads and coauthor of The Native Bromeliads of Florida.
1. What Is an Epiphyte? Getting to Know the Epiphytes Body Plans The Epidermis Other Notable Features of the Epiphytes Starting at the Beginning Geological History Geographic Distribution Use by Humans Conservation 2. The Types of Epiphytes and Their Evolutionary Origins The Free-Living Epiphytes The Biological Underpinnings of Epiphytism How Epiphytism Evolved The Taxonomic Affiliations of the Epiphytes Genetic Heritage and Evolutionary Options Epiphytism and Speciation 3. Epiphytes in Communities and Ecosystems The Nature of Aerial Habitats Mineral Nutrients Water Light Epiphytes as Members of Communities Random Factors Also Structure Communities Ecological Succession What Makes a Tree a Host for Epiphytes? How Epiphytes Can Impact Their Hosts Nutritional Piracy Additional Ways That Epiphytes Harm Their Hosts Manifold Effects on Ecosystems 4. Water Management Variations on Basic Themes How Biological Structure Relates to Function Water Management How Epiphytes Cope with Drought Drought Avoidance Leaf Economics Roots Leaves as Proxies for Roots 5. Photosynthesis and Mineral Nutrition The Photosynthetic Syndromes C3 versus CAM-type Photosynthesis Light and Adaptive Growth Mineral Nutrition The Mistletoes 6. Reproduction and Other Interactions with Animals Pollination Fruits and Seeds Asexual Reproduction Plant Defenses Ants and Epiphytes Termites Leafy Tanks and Phytotelms Case Studies 7. The Epiphytic Monocots Orchidaceae The Vegetative Body Reproduction and Speciation The Adaptive Types Bromeliaceae Bromeliads versus Orchids Adaptations for Epiphytism Hemi-epiphytism The Atmospheric Bromeliads Araceae Amaryllidaceae and Additional Families in Order Liliales 8. The Epiphytic Eudicots Cactaceae General Characteristics Adaptations for Epiphytism Evolutionary History Ecology Reproduction Ericaceae Adaptations for Epiphytism Epiphytism and Speciation Reproductive Biology Horticulture Gesneriaceae Adaptive Variety Evolutionary History Reproductive Biology Rubiaceae Melastomataceae Apocynaceae Solanaceae 9. The Pteridophytic Epiphytes The Major Groups of Pteridophytes The Ferns The Lycophytes 10. Miscellaneous Epiphytes Piperaceae The Carnivorous Epiphytes The Stranglers and Other Primary Hemi-epiphytes The Gymnosperms Additional Oddities 11. Threats and Conservation How Epiphytes Influence Microclimates Contributions to Biodiversity Global Change Excess Nutrients Plant Invasions Habitat Loss Glossary References Subject Index Taxon Index