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  • Print publication year: 2010
  • Online publication date: June 2012

3 - Ecological insights from fern population dynamics


Key points

1. Any comprehensive population study of ferns is based on the demography of the three major stages of the life cycle of ferns (spore, gametophyte and sporophyte) and recognizes asexual alternatives to the main sexual life cycle such as apogamy and vegetative reproduction. Knowledge of spore and gametophyte viability and development in natural habitats is critical to our understanding of the life cycle of ferns and their ecology, but most studies have focused on the larger sporophyte.

2. Classifying sequential life history stages for ferns facilitates the assessment of growth and reproductive responses to environmental stimuli. Recognition of a life history stage in ferns is based on leaf and plant morphology because age estimates for fern individuals are complicated by several problems such as gradually decomposing older tissue in rhizomes of understory ferns and variable growth rates throughout the life of an individual tree fern.

3. Basic phenological variables (e.g., leaf count, leaf and spore production rates, and leaf life span) are monitored for a better understanding of seasonal patterns, population structure and biomass turnover. Factors that influence productivity of ferns have been addressed only recently for tropical species.

4. Population studies have compared different fern species within the same habitat and the ferns have shown surprising sensitivity to microhabitat characteristics. Recent investigations of fern population responses to altitudinal and latitudinal gradients and to environmental changes over time have been based on innovative monitoring methods and transition matrices of life history stages.

5. Future research in fern population dynamics should focus on the connection between critical demographic patterns in ferns and their relevance to comprehensive community and ecosystem studies by using consistent methodologies, expanding into larger geographic ranges (especially in tropical regions) and increasing the focus on long-term monitoring.

Aguraiuja, R., Moora, M. and Zobel, M. (2004). Population stage structure of Hawaiian endemic fern taxa of Diellia (Aspleniaceae): implications for monitoring and regional dynamics. Canadian Journal of Botany, 82, 1438–45.
Allsopp, A. (1965). Heteroblastic development in cormophytes. In Handbuch der Pflanzenphysiologie, ed. Ruhland, W.. Berlin: Springer-Verlag, pp. 1172–221.
Arcand, N., Kagawa, A. K., Sack, L. and Giambelluca, T. W. (2008). Scaling of frond form in Hawaiian tree fern Cibotium glaucum: compliance with global trends and application for field estimation. Biotropica, 40, 686–91.
Arens, N. C. (2001). Variation in performance of the tree fern Cyathea caracasana (Cyatheaceae) across a successional mosaic in an Andean cloud forest. American Journal of Botany, 88, 545–51.
Ash, J. (1986). Demography and production of Leptopteris wilkesiana (Osmundaceae), a tropical tree-fern from Fiji. Australian Journal of Botany, 34, 207–15.
Ash, J. (1987). Demography of Cyathea hornei (Cyatheaceae), a tropical tree-fern in Fiji. Australian Journal of Botany, 35, 331–42.
Bauer, H. C., Gallmetzer, C. and Sato, T. (1991). Phenology and photosynthetic activity in sterile and fertile sporophytes of Dryopteris filix-mas (L.) Schott. Oecologia, 86, 159–62.
Bittner, J. and Breckle, S. W. (1995). The growth rate and age of tree fern trunks in relation to habitats. American Fern Journal, 85, 37–42.
Bremer, P. (1994). On the ecology and population dynamics of a Dutch sporophyte population of Gymnocarpium dryopteris (Woodsiaceae: Pteridophyta). Fern Gazette, 14, 289–98.
Bremer, P. (1995). On the ecology and population dynamics of a Dutch population of Polystichum setiferum (Dryopteridaceae: Pteridophyta). Fern Gazette, 15, 11–20.
Bremer, P. (2004). On the ecology and demography of a terrestrial population of Asplenium trichomanes (Aspleniaceae: Pteridophyta) in the Netherlands. Fern Gazette, 17, 85–96.
Bremer, P. (2007). Ecology and colonisation of ferns in an afforested peat erosion area. In The colonisation of a former sea-floor by fern. Unpublished Ph.D. thesis, Wageningen, The Netherlands: Wageningen University, pp. 37–64.
Bremer, P. and Jongejans, E. (2010). Frost and forest stand effects on the population dynamics of Asplenium scolopendrium L. Population Ecology, 52, 211–22.
Briggs, W. R., and Steeves, T. A. (1958). Morphogenetic studies on Osmunda cinnamomea L.: the expansion and maturation of vegetative fronds. Phytomorphology, 8, 234–48.
Chiou, W.-L., Lin, J.-C. and Wang, J.-Y. (2001). Phenology of Cibotium taiwanense (Dicksoniaceae). Taiwan Journal of Forestry Science, 16, 209–15.
Chiou, W.-L., Martin, C. E., Lin, T. C., et al. (2005). Ecophysiological differences between sterile and fertile fronds of the subtropical epiphytic fern Pyrrosia lingua (Polypodiaceae) in Taiwan. American Fern Journal, 95, 131–40.
Chiou, W.-L., Huang, Y. M., Hsieh, T. H. and Hsu, S. Y. (2006). Diplazium megaphyllum (Bak.) Christ, a rare fern in Taiwan, reproduces by apogamy. Taiwan Journal of Forestry Science, 21, 39–47.
Conant, D. (1976). Ecogeographic and systematic studies in American Cyatheaceae. Unpublished Ph.D. thesis, Harvard University, Cambridge, Massachusetts, USA.
Condit, R. (1995). Research in large, long-term tropical forest plots. Trends in Ecology and Evolution, 10, 18–22.
Cousens, M. I. (1981). Blechnum spicant: habitat and vigor of optimal, marginal, and disjunct populations, and field observations of gametophytes. Botanical Gazette, 142, 251–8.
Cousens, M. I., Lacey, D. G. and Kelly, E. M. (1985). Life-history studies of ferns: a consideration of perspective. Proceedings of the Royal Society of Edinburgh, 86B, 371–80.
Cousens, M. I., Lacey, D. G. and Scheller, J. M. (1988). Safe sites and the ecological life history of Lorinseria areolata. American Journal of Botany, 75, 797–807.
Crotty, W. J. (1955). Trends in the pattern of primordial development with age in the fern Acrostichum danaeifolium. American Journal of Botany, 42, 627–36.
DeSoto, L., Quintanilla, L. G. and Ménez, M. (2008). Environmental sex determination: effects of nutrient availability and individual density in Woodwardia radicans. Journal of Ecology, 96, 1319–27.
Durand, L. Z. and Goldstein, G. (2001). Growth, leaf characteristics, and spore production in native and invasive tree ferns in Hawaii. American Fern Journal, 91, 25–35.
Dyer, A. F. and Lindsay, S. (1992). Soil spore banks of temperate ferns. American Fern Journal, 82, 89–123.
Ellwood, M. D. F., Jones, D. T. and Foster, W. A. (2002). Canopy ferns in lowland dipterocarp forest support a prolific abundance of ants, termites, and other invertebrates. Biotropica, 34, 575–83.
Esteves, L. M. and Dyer, A. F. (2003). The vertical distributions of live and dead fern spores in the soil of a semi-natural woodland in southeast Scotland and their implications for spore movement in the formation of soil spore banks. In Pteridology in the New Millennium, ed. Chandra, S. and Srivastava, M.. Dordrecht, The Netherlands: Kluwer Academic Publishers, pp. 261–82.
Farrar, D. R., Dassler, C., Watkins, J. E., Jr. and Skelton, C. (2008). Gametophyte ecology. In Biology and Evolution of Ferns and Lycophytes, ed. T. A. Ranker and C. H. Haufler. Cambridge, UK: Cambridge University Press, pp. 222–56.
Franklin, J. F., Bledsoe, C. S. and Callahan, J. T. (1990). Contributions of the Long-Term Ecological Research Program. Bioscience, 40, 509–23.
Gaxiola, A., Burrows, L. E. and Coomes, D. A. (2008). Tree fern trunks facilitate seedling regeneration in a productive lowland temperate rain forest. Oecologia, 155, 325–35.
Gay, H. (1993). The architecture of a dimorphic clonal fern, Lomagramma guianensis (Aublet) Ching (Dryopteridaceae). Botanical Journal of the Linnean Society, 111, 343–58.
Gilbert, O. L. (1970). Biological flora of the British Isles, Dryopteris villarii (Bellardi) Woynar. Journal of Ecology, 58, 301–13.
Gillman, L. N. and Ogden, J. (2001). Physical damage by litterfall to canopy tree seedlings in two temperate New Zealand forests. Journal of Vegetation Science, 12, 671–6.
Gotelli, N. J. (1995). A Primer of Ecology. Sunderland, MA, USA: Sinauer Associates, Inc.
Greer, G. K. and McCarthy, B. C. (2000). Patterns of growth and reproduction in a natural population of the fern Polystichum acrostichoides. American Fern Journal, 90, 60–76.
Gureyeva, I. I. (2003). Demographic studies of homosporous fern populations in South Siberia. In Pteridology in the New Millennium, ed. Chandra, S. and Srivastava, M.. Dordrecht, The Netherlands: Kluwer Academic Publishers, pp. 341–64.
Halleck, L. F., Sharpe, J. M. and Zou, X. (2004). Understorey fern responses to post-hurricane fertilization and debris removal in a Puerto Rican rain forest. Journal of Tropical Ecology, 20, 173–81.
Halpern, C. B., Evans, S. A. and Nielson, S. (1999). Soil seed banks in young, closed-canopy forests of the Olympic Peninsula, Washington: potential contributions to understory reinitiation. Canadian Journal of Botany, 77, 922–35.
Hamilton, R. G. (1988). The significance of spore banks in natural populations. American Fern Journal. 78, 96–104.
Hamilton, R. G. (1992). Allozyme variation and ramet distribution in two species of athyriod ferns. Plant Species Biology, 7, 69–76.
Hammen, S. C. L. (1993). Density-dependent phenotypic variation in the hay-scented fern, Dennstaedtia punctilobula. Bulletin of the Torrey Botanical Club, 120, 392–6.
Harper, J. L. (1977). Population Biology of Plants. New York: Academic Press.
Harper, J. L. (1982). After description. In The Plant Community as a Working Mechanism, ed. Newman, E. I.. Boston, MA, USA: Blackwell Scientific, pp. 11–25.
Headley, A. D. and Callaghan, T. V. (1990). Modular growth of Huperzia selago (Lycopodiaceae: Pteridophyta). Fern Gazette, 13, 361–72.
Hebant-Mauri, R. and Gay, H. (1993). Morphogenesis and its relation to architecture in the dimorphic clonal fern Lomagramma guianensis (Aublet) Ching (Dryopteridaceae). Botanical Journal of the Linnean Society, 112, 257–76.
Hoshizaki, B. J. and Moran, R. C. (2001). Fern Grower's Manual. Portland, OR, USA: Timber Press.
Jaag, O. (1943). Ergebnisse einer botanischen Studienreise nach Niederländisch-Indien 1937/38. I. Untersuchungen über den Rhythmus der Lauberneuerung, die Lebensdauer der Blätter and den Epiphytenbefall bei einigen Farnen in den Tropen. Mitteilungen der Naturforschenden Gesellschaft Schaffhausen, 18, 205–57.
Johns, R. J. and Edwards, P. J. (1991). Vegetative reproduction in pteridophytes. Kew Magazine, 8, 109–12.
Johnson-Groh, C. (1999). Population ecology of Botrychium (moonworts): status report on Minnesota Botrychium permanent plot monitoring. Report for Gustavus Adolphus College, Saint Peter, MN, USA.
Johnson-Groh, C., Riedel, C., Schoessler, L. and Skogen, K. (2002). Belowground distribution and abundance of Botrychium gametophytes and juvenile sporophytes. American Fern Journal, 92, 80–92.
Jones, D. (1987). Encyclopaedia of Ferns. Portland, OR, USA: Timber Press.
Kato, M. and Setoguchi, H. (1999). An rbcL-based phylogeny and heteroblastic leaf morphology of Matoniaceae. Systematic Botany, 23, 391–400.
Kelly, D. (1994). Demography and conservation of Botrychium australe, a peculiar, sparse mycorrhizal fern. New Zealand Journal of Botany, 32, 393–400.
Kenkel, N. C. (1997). Demography of clonal ostrich fern (Matteuccia struthiopteris): a five year summary. University of Manitoba, UFS (Delta Marsh) Annual Report, 32, 75–9.
Kornaś, J. (1977). Life forms and seasonal patterns in the pteridophytes of Zambia. Acta Societatis Botanicorum Poloniae, 46, 669–90.
Large, M. F. and Braggins, J. E. (2004). Tree Ferns. Portland, OR, USA: Timber Press.
Lee, P.-H., Huang, Y.-M. and Chiou, W.-L. (2008). The phenology of Osmunda claytoniana L. in the Tataka area, Central Taiwan. Taiwan Journal of Forest Science, 23, 71–9.
Lee, P.-H., Lin, T.-T. and Chiou, W.-L. (2009). Phenology of 16 species of ferns in a subtropical forest of northeastern Taiwan. Journal of Plant Research, 122, 61–7.
Lefkovitch, L. P. (1965). The study of population growth in organisms grouped by stages. Biometrics, 21, 1–18.
Lellinger, D. B. (2002). A modern multilingual glossary for taxonomic pteridology. Pteridologia, 3, 1–264.
Lindsay, S. and Dyer, A. F. (1996). Investigating the phenology of gametophyte development: an experimental approach. In Pteridology in Perspective, ed. Camus, J. M., Gibby, M. and Johns, R. J.. Kew, UK: Royal Botanic Gardens, pp. 633–50.
Mehltreter, K. (2006). Leaf phenology of the climbing fern Lygodium venustum in a semideciduous lowland forest on the Gulf of Mexico. American Fern Journal, 96, 21–30.
Mehltreter, K. (2008). Phenology and habitat specificity of tropical ferns. In Biology and Evolution of Ferns and Lycophytes, ed. Ranker, T. A. and Haufler, C. H.. Cambridge, UK: Cambridge University Press, pp. 201–21.
Mehltreter, K. and García-Franco, J. G. (2008). Leaf phenology and trunk growth of the deciduous tree fern Alsophila firma (Baker) D.S. Conant in a lower montane Mexican forest. American Fern Journal, 98, 1–13.
Mehltreter, K. and Palacios-Rios, M. (2003). Phenological studies of Acrostichum danaeifolium (Pteridaceae, Pteridophyta) at a mangrove site on the Gulf of Mexico. Journal of Tropical Ecology, 19, 155–62.
Milton, S. J. (1987a). Growth of seven-weeks fern (Rumohra adiantiformis) in Southern Cape forests: implications for management. South African Forestry Journal, 143, 1–4.
Milton, S. J. (1987b). Effects of harvesting on four species of forest ferns in South Africa. Biological Conservation, 41, 133–46.
Montgomery, J. (1990). Survivorship and predation changes in five populations of Botrychium dissectum in Eastern Pennsylvania. American Fern Journal, 80, 173–82.
Moran, R. C. (1987). Sterile–fertile leaf dimorphy and evolution of soral types in Polybotrya (Dryopteridaceae). Systematic Botany 12: 617–28.
Moran, R. C. (2004). A Natural History of Ferns. Portland, OR: Timber Press.
Nagano, T. and Suzuki, E. (2007). Leaf demography and growth pattern of the tree fern Cyathea spinulosa on Yakushima Island. Tropics, 10, 47–57.
Nobel, P. S. (1978). Microhabitat, water relations, and photosynthesis of a desert fern, Notholaena parryi. Oecologia, 31, 293–309.
Noss, R. F. (1999). Assessing and monitoring forest biodiversity: a suggested framework and indicators. Forest Ecology and Management, 115, 135–46.
Odland, A. (1995). Frond development and phenology of Thelypteris limbosperma, Athyrium distentifolium and Matteuccia struthiopteris in Western Norway. Nordic Journal of Botany, 15, 225–36.
Odland, A. (1998). Size and reproduction of Thelypteris limbosperma and Athyrium distentifolium along environmental gradients in western Norway. Nordic Journal of Botany, 18, 311–21.
Odland, A., Junttila, O. and Nilsen, J. (2004). Growth responses of Matteuccia struthiopteris plants from northern and southern Norway exposed to different temperature and photoperiod and treatments. Nordic Journal of Botany, 23, 237–46.
Ogura, Y. (1972). Comparative Anatomy of the Vegetative Organs of the Pteridophytes. Handbuch der Pflanzenanatomie. Stuttgart, Germany: Borntraeger.
Oinonen, E. (1967a). The correlation between the size of Finnish bracken (Pteridium aquilinum (L.) Kuhn) clones and certain periods of site history. Acta Forestalia Fennica, 83(2), 1–51.
Oinonen, E. (1967b). Sporal regeneration of ground pine (Lycopodium complanatum L.) in southern Finland in the light of the size and age of its clones. Acta Forestalia Fennica, 83(1), 1–96.
Oinonen, E. (1971). The time table of vegetative spreading in oak fern (Carpogymnia dryopteris (L.) Love and Love) and may-lily (Maianthemum bifolium (L.) F. W. Schmidt) in southern Finland. Acta Forestalia Fennica, 118, 1–21.
Øllgaard, B. (1979). Studies in Lycopodiaceae. II. The branching patterns and infrageneric groups of Lycopodium sensu lato. American Fern Journal, 69, 49–61.
Orth, R. (1938). Zur Morphologie der Primärblatter einheimischer Farne. Flora, 33, 1–55.
Page, C. N. (1997). The Ferns of Britain and Ireland. Cambridge, UK: Cambridge University Press.
Page, C. N. and Brownsey, P. J. (1986). Tree-fern skirts: a defence against climbers and large epiphytes. Journal of Ecology, 74, 787–96.
Peck, J. H., Peck, C. J. and Farrar, D. R. (1990). Influences of life history attributes on formation of local and distant fern populations. American Fern Journal, 80, 126–42.
Pinero, D., Martinez-Ramoz, M., Mendoza, A., Alvarez-Buylla, E. and Sarukhan, J. (1986). Demographic studies in Astrocaryum mexicanum and their use in understanding community dynamics. Principes, 30, 108–16.
Primack, R. B. (1973). Growth patterns of five species of Lycopodium. American Fern Journal, 63, 3–7.
Proctor, G. R. (1989). Ferns of Puerto Rico and the Virgin Islands. Memoirs of the New York Botanical Garden, 53, 1–389.
Prugnolle, F., Rousteau, A. and Belin-Depoux, M. (2000). Occupation spatiale de Cyathea muricata Willd. (Cyatheaceae) en foret dense humide guadeloupeenne. I. A l'echelle de l'individu. Acta Botanica Gallica, 147, 361–74.
Pryer, K. M., Buler, E. Y., Farrar, D., et al. (2008). On the importance of portraying the plant life cycle accurately: ferns as a case study. Abstracts of Botany 2008. Botanical Society of America. Viewed December 2008.
Punetha, N. (1989). Leaf growth and productivity in two western Himalayan thelypteroid ferns. Indian Fern Journal, 6, 68–72.
Ramirez-Trejo, M. D. R., Perez-Garcia, B. and Orozco-Segovia, A. (2004). Analysis of fern spore banks from the soil of three vegetation types in the central region of Mexico. American Journal of Botany, 91, 682–8.
Ranal, M. A. (2003). Soil spore banks of ferns in a gallery forest of the ecological station of Panga, Uberlandia, MG. Brazil. American Fern Journal, 93, 97–115.
Reich, P. B., Uhl, C., Walters, M. B., Prugh, L. and Ellsworth, D. S. (2004). Leaf demography and phenology in Amazonian rain forest: a census of 40,000 leaves of 23 tree species. Ecological Monographs, 74, 3–23.
Rodrigues, A. S. L., Andelman, S. J., Bakarr, , et al. (2004). Effectiveness of the global protected area network in representing species diversity. Nature, 428, 640–2.
Rubin, G., Robson, D. S. and Paolillo, D. J. (1985). Effects of population density on sex expression in Onoclea sensibilis L. on agar and ashed soil. Annals of Botany, 55, 201–15.
Russell, A. E., Raich, J. W. and Vitousek, P. M. (1998). The ecology of the climbing fern Dicranopteris linearis on windward Mauna Loa, Hawaii. Journal of Ecology, 86, 765–79.
Sanford, R. L., Braker, H. E. and Hartshorn, G. S. (1986). Canopy openings in a primary neotropical lowland forest. Journal of Tropical Ecology, 2, 277–82.
Sato, T. (1982). Phenology and wintering capacity of sporophytes and gametophytes of ferns native to northern Japan. Oecologia, 55, 53–61.
Sato, T. (1985). Quantitative expression of fern leaf development and fertility in Polystichum tripteron (Aspidiaceae). Plant Systematics and Evolution, 150, 191–200.
Sato, T. (1990a). Estimation of chronological age for sporophyte maturation in three semi-evergreen ferns in Hokkaido. Ecological Research, 5, 55–62.
Sato, T. (1990b). A quantitative comparison of foliage development among allopatric ferns, Dryopteris crassirhizoma, D. coreano-montana and D. filix-mas. Botanical Magazine, 103, 165–76.
Sato, T. and Tsuyuzaki, S. (1988). Quantitative comparison of foliage development among Dryopteris monticola, D. tokyoensis and a putative hybrid, D. kominatoensis in northern Japan. Botanical Magazine, 101, 267–80.
Schmitt, J. L. and Windisch, P. G. (2006). Growth rates and age estimates of Alsophila setosa Kaulf. in southern Brazil. American Fern Journal, 96, 103–11.
Schmitt, J. L. and Windisch, P. G. (2007). Estrutura populacional e desenvolvimento da fase esporifitica de Cyathea delgadii Sternb. (Cyatheaceae, Monilophyta) no sul do Brasil. Acta Botanica Brasilica, 21, 731–40.
Schneller, J. J. (2008). Antheridiogens. In Biology and Evolution of Ferns and Lycophytes, ed. Ranker, T. A. and Haufler, C. H.. Cambridge, UK: Cambridge University Press, pp. 134–58.
Seiler, R. L. (1981). Leaf turnover rates and natural history of the Central American tree fern Alsophila salvinii. American Fern Journal, 71, 75–81.
Sharpe, J. M. (1988). Growth, demography, tropic responses and apical dominance in the neotropical fern Danaea wendlandii Reichenb. (Marattiaceae). Unpublished Ph.D. thesis, University of Georgia, Athens, Georgia, USA.
Sharpe, J. M. (1993). Plant growth and demography of the neotropical herbaceous fern Danaea wendlandii (Marattiaceae) in a Costa Rican rain forest. Biotropica, 25, 85–94.
Sharpe, J. M. (1997). Leaf growth and demography of the rheophytic fern Thelypteris angustifolia (Willdenow) Proctor in a Puerto Rican rainforest. Plant Ecology, 130, 203–12.
Sharpe, J. M. (2005). Temporal variation in sporophyte fertility in Dryopteris intermedia and Polystichum acrostichoides (Dryopteridaceae: Pteridophyta). Fern Gazette, 17, 223–34.
Sharpe, J. M. (in press). Responses of the mangrove fern Acrostichum danaeifolium Langsd. & Fisch. (Pteridaceae, Pteridophyta) to disturbances resulting from increased soil salinity and Hurricane Georges at the Jobos Bay National Estuarine Research Reserve, Puerto Rico. Wetlands Ecology and Management.
Sharpe, J. M. and Jernstedt, J. A. (1990a). Leaf growth and phenology of the dimorphic herbaceous layer fern Danaea wendlandii (Marattiaceae) in a Costa Rican rain forest. American Journal of Botany, 77, 1040–9.
Sharpe, J. M. and Jernstedt, J. A. (1990b). Tropic responses controlling leaf orientation in the fern Danaea wendlandii (Marattiaceae). American Journal of Botany, 77, 1050–9.
Sharpe, J. M. and Jernstedt, J. A. (1991). Stipular bud development in Danaea wendlandii (Marattiaceae). American Fern Journal, 81, 119–27.
Sheffield, E. (2008). Alternation of generations. In Biology and Evolution of Ferns and Lycophytes, ed. Ranker, T. A. and Haufler, C. H.. Cambridge, UK: Cambridge University Press, pp. 49–74.
Silvertown, J. W. (1982). Introduction to Plant Population Ecology. London: Longman.
Siman, S. E. and Sheffield, E. (2002). Polypodium vulgare plants sporulate continuously in a non-seasonal glasshouse environment. American Fern Journal, 92, 30–8.
Steeves, T. A. (1959). An interpretation of two forms of Osmunda cinnamomea. Rhodora, 61, 223–30.
Szmeja, J. (1994). An individual's status in populations of isoetid species. Aquatic Botany, 48, 203–24.
Takahashi, K. and Mikami, Y. (2006). Effects of canopy cover and seasonal reduction in rainfall on leaf phenology and leaf traits of the fern Oleandra pistillaris in a tropical montane forest, Indonesia. Journal of Tropical Ecology, 22, 599–604.
Tanner, E. V. J. (1983). Leaf demography and growth of the tree-fern Cyathea pubescens Mett. ex Kuhn in Jamaica. Botanical Journal of the Linnean Society, 87, 213–27.
Tryon, A. F. (1990). Fern spores: evolutionary levels and ecological differentiation. Plant Systematics and Evolution, Supplement 5, 71–9.
Tryon, A. F. and Lugardon, B. (1990). Spores of the Pteridophyta. New York: Springer-Verlag.
Tryon, R. M. and Tryon, A. F. (1982). Ferns and Allied Plants with Special Reference to Tropical America. New York: Springer-Verlag.
Vöge, M. (1997a). Plant size and fertility of Isoëtes lacustris L. in 20 lakes of Scandinavia: a field study. Archiv für Hydrobiology, 139, 171–85.
Vöge, M. (1997b). Number of leaves per rosette and fertility characters of the quillwort (Isoëtes lacustris L.) in 50 lakes in Europe: a field study. Archiv für Hydrobiology, 139, 415–31.
Vöge, M. (2004). Non-destructive assessing and monitoring of populations of Isoëtes lacustris L. Limnologica, 34, 147–53.
Vöge, M. (2006). The reproductive phenology of Isoëtes lacustris L.: results of field studies in Scandinavian lakes. Limnologica, 36, 228–33.
Wagner, W. H. and Wagner, F. S. (1977). Fertile–sterile leaf dimorphy in ferns. The Gardens' Bulletin, Singapore, 30, 251–67.
Walker, L. R. and Aplet, G. H. (1994). Growth and fertilization responses of Hawaiian tree ferns. Biotropica, 26, 378–83.
Walker, L. R., Zimmerman, J. K., Lodge, D. J. and Guzman-Grajales, S. (1996). An altitudinal comparison of growth and species composition in hurricane-damaged forests in Puerto Rico. Journal of Ecology, 84, 877–89.
Walker, T. G. (1985). Some aspects of agamospory in ferns – the Braithwaite system. Proceedings of the Royal Society of Edinburgh, 86B, 59–66.
Watkins, J. E.., Mack, M. K. and Mulkey, S. S. (2007). Gametophyte ecology and demography of epiphytic and terrestrial tropical ferns. American Journal of Botany, 94, 701–8.
Watt, A. S. (1943). Contributions to the ecology of bracken (Pteridium aquilinum). II. The frond and the plant. New Phytologist, 42, 103–26.
Watt, A. S. (1976). The ecological status of bracken. Botanical Journal of the Linnean Society, 73, 217–39.
Werth, C. R. and Cousens, M. I. (1990). Summary: The contribution of population studies on ferns. American Fern Journal, 80, 183–90.
Whittier, D. (2003a). The gametophyte of Diphasiastrum sitchense. American Fern Journal, 93, 20–4.
Whittier, D. (2003b). Rapid gametophyte maturation in Ophioglossum crotalophoroides. American Fern Journal, 93, 137–45.
Whittier, D. (2006). Gametophytes of four tropical, terrestrial Huperzia species (Lycopodiaceae). American Fern Journal, 96, 54–61.
Whittier, D. and Storchova, H. (2007). The gametophyte of Huperzia selago in culture. American Fern Journal, 97, 149–154.
Wick, H. L. and Hashimoto, G. T. (1971). Leaf Development and Stem Growth of Treefern in Hawaii. Berkeley, California: U.S. Forest Service Research Note PSW-237, Pacific Southwest Forest and Range Experiment Station.
Willmot, A. (1989). The phenology of leaf life spans in woodland populations of the ferns Dryopteris filix-mas (L.) Schott and D. dilatata (Hoffm.) A. Gray in Derbyshire. Botanical Journal of the Linnean Society, 99, 387–95.