|FEIS Home Page|
Small-leaf climbing fern is native to tropical and subtropical areas of Africa, southeastern Asia, northern and eastern Australia, and the Pacific islands (reviewed by [5,24]). In North America it is found in southern and central Florida [21,44]. Large parts of the Caribbean, Central and South America, and perhaps coastal areas of southern Louisiana and Texas may also be vulnerable to small-leaf climbing fern invasion [10,23,25]. Small-leaf climbing fern was first collected from the wild in southern Florida in 1960 . As of 2005, Florida Plant Atlas  showed small-leaf climbing fern distribution in southern Florida from coast to coast and as far north as Hillsborough and Brevard counties. Ecological/climate modeling indicates small-leaf climbing fern could become established throughout most of southern Florida, with northern distribution extending furthest along the coasts .
Ferriter  reviewed the history of climbing fern invasion in the southeastern U.S.
The Flora of North America provides distribution maps of climbing ferns.
The following biogeographic classification systems demonstrate where Japanese climbing fern
(labeled with the abbreviation J) and small-leaf climbing fern (O) could potentially be found
based on floras and other literature, herbarium samples, and confirmed observations.
Precise distribution information is unavailable. In general, predicting distribution of
nonnative species in North America is difficult due to gaps in understanding of their
biological and ecological characteristics, and because they may still be expanding their
range. Therefore, these lists are speculative and may be imprecise.
FRES12 Longleaf-slash pine JO
FRES13 Loblolly-shortleaf pine J
FRES14 Oak-pine J
FRES15 Oak-hickory J
FRES16 Oak-gum-cypress J
FRES39 Prairie J
FRES41 Wet grasslands JO
STATES/PROVINCES: (key to state/province abbreviations)
Japanese climbing fern:
A survey of Big Branch Marsh National Wildlife Refuge in southeastern Louisiana found Japanese climbing fern "well established" in both American beech (Fagus grandifolia)-southern magnolia (Magnolia grandiflora) woods and "mixed woods" (successional forests dominated by loblolly pine (Pinus taeda)) .
A review by Pemberton and Ferriter  indicates that small-leaf climbing fern is common in bald cypress (Taxodium distichum) stands and also occurs in pine (Pinus spp.) flatwoods, wet prairies, sawgrass (Cladium jamaicense) marshes, mangrove (Rhizophora, Avicennia, and/or Laguncularia spp.) communities, and Everglades tree islands. Volin and others  found that presence of small-spike false nettle (Boehmeria cylindrica), royal fern (Osmunda regalis), resurrection fern (Pleopeltis polypodioides ssp. polypodioides), and toothed midsorus fern (Blechnum serrulatum) were significant (p<0.05) indicators of small-leaf climbing fern occurrence in Big Cypress National Preserve and Big Cypress Seminole Indian Reservation, southern Florida.
Japanese climbing fern fronds are from 3.3 to 100 feet (1-30.5 m) in length [1,3,27], and small-leaf climbing fern fronds grow to 90 feet (27 m) long . In Japanese climbing ferns, pinnae (groups of leaflets) are up to 12 inches (30 cm) wide, and are subdivided into 2 or 3 pinnules (leaflets) up to 3 inches (8 cm) long and 6 inches (15 cm) wide [27,28]. Small-leaf climbing fern pinnae are 2 to 5 inches (5-13 cm) long with several pairs of pinnules . Fertile pinnules of small-leaf climbing fern are fringed with tiny lobes of enrolled leaf tissue along the margin, which cover the reproductive tissues . Japanese climbing fern sporangia are borne on narrow, fingerlike segments of the pinnae .
|Japanese climbing fern||Small-leaf climbing fern|
|©John M. Randall/The Nature Conservancy||©Mandy Tu/The Nature Conservancy|
In addition to their photosynthetic and reproductive functions, adult climbing fern fronds are analogous to the twining shoots of flowering plants, spreading along the ground, over shrubs, or climbing by twining around other structures, such as trees and other vines [3,15,18,27]. Twining growth is indeterminate and occurs at a steady rate [18,19,26]. Annual height increase averaged (± SE) 3.81 ± 0.07 feet (1.16 ± 0.02 m) for small-leaf climbing fern growing on infested trees in Jonathon Dickinson State Park and Big Cypress Seminole Indian Reservation, southern Florida .
Climbing ferns are rhizomatous [3,27]. Rhizomes grow 0.4 to 1.2 inches (1-3 cm) below soil surface .
Climbing ferns are evergreen in subtropical environments .
RAUNKIAER  LIFE FORM:
Breeding system: Climbing ferns reproduce sexually by spores. They are capable of intragametophytic selfing. Small-leaf climbing fern can also reproduce via intergametophytic selfing and outcrossing [16,39]. Lott and others  suggested that small-leaf climbing fern's mixed mating system facilitates long distance dispersal, as well as local adaptation in established populations.
Spore production: Volin and others  studied small-leaf climbing fern spore production at 2 sites in southern Florida. Approximately 1% of pinnules were fertile. Fertile pinnules averaged 133 sori, with an average of 215 spores per sorus. Each fertile pinnule could potentially produce 28,600 spores or ~15,000 spores per cm2 of fertile leaf area .
Spore dispersal: Climbing fern spores are wind-dispersed, potentially over great distances, particularly during storms [5,15,25]. Pemberton (unpublished data, reported in ) recorded 724 small-leaf climbing fern spores/m3/hour in the air in southeastern Florida.
Spore longevity: Climbing fern spores are thick-walled, providing "long environmental viability" (reviewed by ).
Plant establishment/growth: In a laboratory experiment, climbing fern gametophytes were sexually mature within 5 weeks of germination, followed by sporophyte production through week 12. Rapid development/reproductive rates may be an advantage in many Florida habitats where seasonal environmental conditions such as hydroperiod can vary widely .
Asexual regeneration: Small-leaf climbing fern (and presumably Japanese climbing fern) can apparently regrow aboveground tissues that are damaged by herbicides, mechanical injury, fire , or that are killed to the ground by frost (reviewed by ), although details describing this biology are lacking.SITE CHARACTERISTICS:
Climbing ferns do not seem well-adapted to extremely dry habitats or soils with exceptionally long hydroperiods (reviewed by ). Nauman and Austin  reported that small-leaf climbing fern is "confined to wet, disturbed sites...found only near canals, rivers, ditches, in disturbed swamps, and other sites which have standing water for a large part of the year." Volin and others  reported that small-leaf climbing fern presence within study sites in Big Cypress National Preserve and Big Cypress Seminole Indian Reservation, southern Florida, was significantly (p<0.05) correlated to hydrology, "coinciding with a wet, but not permanently inundated environment."
Aboveground portions of climbing ferns are killed by frost, but roots may be protected [5,25,41].
This is particularly true, at least for small-leaf climbing fern, when roots are growing in standing
water (reviewed by ). Japanese climbing fern foliage is killed by freezing temperatures,
but browned fronds often remain draped in shrub and tree canopies enabling new growth easier access
to the same habitat once favorable temperatures for growth resume . A modeling exercise
conducted by Goolsby  indicated that, although small-leaf climbing fern appears intolerant
of freezing temperatures, it may be tolerant of near-freezing temperatures if daytime maximums
are warm. Pemberton and Ferriter  suggested that small-leaf climbing fern may eventually
extend its range into portions of northern and central Florida that are within USDA Plant
Hardiness Zone 9b . However, its occurrence may be limited by insufficient heating degree-days.
Although damage from cold, but above-freezing temperatures may not be apparent, reduced growth
during prolonged periods of cool weather may limit small-leaf climbing fern competitiveness .
Late-successional, forested habitats may be particularly vulnerable to climbing fern invasion. A review by Pemberton and others  indicates that small-leaf climbing fern can colonize undisturbed habitat. Volin and others  reported that small-leaf climbing fern coverage in Big Cypress National Preserve and Big Cypress Seminole Indian Reservation, southern Florida, was greatest "in a low-light understory environment." Preliminary results from a laboratory experiment by Volin and others  suggested that climbing ferns, and particularly small-leaf climbing fern, are comparatively better adapted to growing under low light conditions than the 2 native vines, muscadine (Vitis rotundifolia) and Virginia creeper (Parthenocissus quinquefolia). Apparent advantages were attributed to greater photosynthetic rates and greater relative leaf area . Observations suggest that Japanese climbing fern fronds form a dense canopy that can cast substantial shade, potentially suppressing understory plant growth and recruitment .
As of this writing (2005) there is very little published information describing climbing fern phenology. Japanese climbing fern "flowering and fruiting" occurs from June to September in the Carolinas . While small-leaf climbing fern spore production occurs year-round, spore production and leaf area both reach a seasonal peak during the wet season (September-November) .
Fire adaptations: Although it is likely that climbing ferns can regenerate following fire (see Plant Response To Fire), as of this writing (2005) there are no published descriptions of climbing fern fire adaptations.
Fire regimes: Climbing ferns may alter fire regimes by providing ladder fuels, leading to greater incidence of crown fire in communities that are ill-adapted to crown fire (reviewed by ).
The following table provides fire return intervals for plant communities and ecosystems where climbing ferns are important. For further information, see the FEIS review of the dominant species listed below. This list may not be inclusive for all plant communities in which climbing ferns occur. Find further fire regime information for the plant communities in which these species may occur by entering the species' names in the FEIS home page under "Find Fire Regimes".
|Climbing fern spp.**||Community or Ecosystem||Dominant Species||Fire Return Interval Range (years)|
|J||bluestem-Sacahuista prairie||Andropogon littoralis-Spartina spartinae||<10 |
|O||mangrove||Avicennia nitida-Rhizophora mangle||35-200 |
|J||sugarberry-America elm-green ash||Celtis laevigata-Ulmus americana-Fraxinus pennsylvanica||<35 to 200|
|J||Atlantic white-cedar||Chamaecyparis thyoides||35 to >200|
|J||yellow-poplar||Liriodendron tulipifera||<35 |
|JO||melaleuca||Melaleuca quinquenervia||<35 to 200 |
|J||shortleaf pine||Pinus echinata||2-15|
|J||shortleaf pine-oak||Pinus echinata-Quercus spp.||<10|
|JO||slash pine||Pinus elliottii||3-8|
|JO||slash pine-hardwood||Pinus elliottii-variable||<35 |
|JO||South Florida slash pine||Pinus elliottii var. densa||1-15 [20,33,40]|
|JO||longleaf-slash pine||Pinus palustris-P. elliottii||1-4 [20,40]|
|J||pond pine||Pinus serotina||3-8|
|J||loblolly pine||Pinus taeda||3-8|
|J||loblolly-shortleaf pine||Pinus taeda-P. echinata||10 to <35|
|J||Virginia pine||Pinus virginiana||10 to <35|
|J||Virginia pine-oak||Pinus virginiana-Quercus spp.||10 to <35|
|J||sycamore-sweetgum-American elm||Platanus occidentalis-Liquidambar styraciflua-Ulmus americana||<35 to 200 |
|J||eastern cottonwood||Populus deltoides||<35 to 200 |
|J||mesquite||Prosopis glandulosa||<35 to <100 [17,22]|
|J||oak-hickory||Quercus-Carya spp.||<35 |
|J||oak-gum-cypress||Quercus-Nyssa-spp.-Taxodium distichum||35 to >200 |
|J||southeastern oak-pine||Quercus-Pinus spp.||<10|
|J||white oak-black oak-northern red oak||Quercus alba-Q. velutina-Q. rubra||<35|
|J||post oak-blackjack oak||Quercus stellata-Q. marilandica||<10|
|J||black oak||Quercus velutina||<35|
|J||live oak||Quercus virginiana||10 to<100 |
|JO||cabbage palmetto-slash pine||Sabal palmetto-Pinus elliottii||<10 [20,40]|
|J||southern cordgrass prairie||Spartina alterniflora||1-3 |
|JO||bald cypress||Taxodium distichum||100 to >300|
|JO||pond cypress||Taxodium ascendens||<35 |
Climbing fern presence may instigate changes in fire behavior. Small-leaf climbing fern presence in southern Florida forests has been associated with greater incidence of crown fire, due to an increase in ladder fuels. Also, burning mats of small-leaf climbing fern may be lofted by convection and ignite spot fires downwind from the main fire (reviewed by ). There are also suggestions that climbing fern presence in forest canopies may carry fire through wet areas that would otherwise present a boundary to fire spread (reviewed by ).
Palatability/nutritional value: No information is available on this topic.
No information is available on this topic.
Climbing ferns were originally imported and sold in the United States as ornamentals . In their native ranges, climbing fern spores are used for medicinal purposes and the rachis is used for weaving (reviewed by ).
IMPACTS AND CONTROL:
Impacts: Although there are few studies documenting the impacts of climbing ferns on native plants and ecosystems in the southeastern U.S., their invasion is likely to have deleterious effects. Nauman and Austin  reported that climbing ferns are established, persistent, and spreading in Florida, Japanese climbing fern in the north and small-leaf climbing fern in the south. A review by Ferriter  suggested that climbing ferns don't require "human disturbance in order to spread and become established."
Most accounts of impacts associated with climbing fern invasion (e.g. reviews by [1,15,16,21,25,41]) describe interference with native plants due to a prodigious growth habit. Climbing ferns can produce thick mats along the ground, severely reducing native ground cover. A review by Wood ) indicated that small-leaf climbing fern can form mats up to 4 feet (1.2 m) thick. They also climb into forest canopies, shading trees and shrubs that it covers, weakening or killing them, their associated epiphytic orchids and bromeliads, and understory plants.
|Japanese climbing fern||Small-leaf climbing fern|
|©Barry A. Rice/The Nature Conservancy||©Mandy Tu/The Nature Conservancy|
Of particular concern may be climbing fern impacts on native vegetation within many of the region's high-quality natural areas. A review by Pemberton and others  indicated that, as of 2004, small-leaf climbing fern was rapidly spreading in southern Florida, including in Everglades National Park. Volin and other  expressed concern that efforts to restore Everglades hydrology to approximate a "pre-drainage environment," while perhaps reducing establishment and spread of many important nonnative plant invaders, may "improve the ecological conditions for small-leaf climbing fern." Lott and others  reported that small-leaf climbing fern "has been observed overtopping tree canopies among tree islands in the Arthur R. Marshall Loxahatchee National Wildlife Refuge" . Volin and others  recorded an average of 14 small-leaf climbing fern infestations (defined as contiguous growth that had climbed above the shrub layer on 1 or more trees) per km2 along transects in the Big Cypress National Preserve and Big Cypress Seminole Indian Reservation. The most heavily infested transect contained 58 infestations per km 2.
Climbing fern invasion may also impact rare and threatened taxa. Reviews by Ferriter  and Langeland  indicate that climbing fern invasion in Florida threatens the rare plant ray fern (Actinostachys pennula), as well as the endangered Georgia bully (Sideroxylon thornei), common dutchmanspipe (Aristolochia tomentosa), and branched tearthumb (Polygonum meisnerianum).
Control: Removing dead material following climbing fern control activities may be desirable to reduce fuels and to promote native plant recovery. On-site disposal of dead climbing fern material, such as by burning, can reduce spore dispersal (reviewed by ).
Ferriter  provides an extensive review of climbing fern management in Florida, available online through Florida Exotic Pest Plant Council.
Prevention: Frequent monitoring and immediate removal of newly established climbing fern populations may be the best strategy for mitigating their spread, especially since spore production can be prolific and spores may be dispersed over vast distances .
Integrated management: No information is available on this topic.
Physical/mechanical: Repeated pulling and/or cutting can control small climbing fern infestations (reviewed by ). Cutting kills fronds above the cut site, but fronds can regrow from below the cut site and after pulling (reviewed by ).
Fire: See the Fire Management Considerations section of this summary.
Biological: Pemberton  and Pemberton and others  reviewed the developmental status (as of 2004) of biological control of climbing ferns in North America. In February 2005, more than 100 individuals of Austromusotima camptonozale, an Australian moth and the first biological control agent approved for use against small-leaf climbing fern in the United States, were released at the Jonathon Dickinson State Park, southeastern Florida. Larvae of A. camptonozale feed on small-leaf climbing fern leaves .
Chemical: Several sources indicate herbicides may be an effective tool for controlling invasive climbing ferns. A review by Langeland  suggests the most common climbing fern control method, as of 2004, has been application of glyphosate and metsulfuron herbicides, either individually or in combination. When plants have grown into the canopy, stems may be cut and herbicide applied to the rooted portion of the plant . Roberts  indicated foliar spraying of glyphosate can control small-leaf climbing fern, but few data and no analysis were provided. Descriptive results from several "demonstration trials" in southeastern Florida suggest that glyphosate, triclopyr, and 2,4-D can be used to at least top-kill small-leaf climbing fern, and that triclopyr ester (vs. triclopyr amine) may be "translocated" within the plant following application . According to Randall , managers at Florida Caverns State Park have treated large Japanese climbing fern infestations by pulling the plants down from the trees and spraying their foliage with triclopyr. A review by Ferriter , citing unpublished data, indicated that glyphosate was effective for controlling Japanese climbing fern, although some follow-up spot treatments were necessary. Triclopyr treatments, while initially providing greatest observed Japanese climbing fern mortality, were ineffective in the long term due to extensive regrowth.
Other authors have indicated that herbicide use for climbing fern control may be problematic. A review by Stanturf and others  suggested that Japanese climbing fern "cannot be controlled by any available herbicide." Small-leaf climbing fern can apparently "regrow after spraying" with herbicides (reviewed by ), although further details describing the biology of this phenomenon are lacking. Pemberton and Ferriter  suggested that chemical control of small-leaf climbing fern (and presumably also Japanese climbing fern) will be difficult without damaging associated vegetation.
Cultural: No information is available on this topic.
1. Anon. 1992. Exotic fern a threat to wetlands. Restoration & Management Notes. 10(2): 199. [Abstract]. 
2. Bernard, Stephen R.; Brown, Kenneth F. 1977. Distribution of mammals, reptiles, and amphibians by BLM physiographic regions and A.W. Kuchler's associations for the eleven western states. Tech. Note 301. Denver, CO: U.S. Department of the Interior, Bureau of Land Management. 169 p. 
3. Clewell, Andre F. 1985. Guide to the vascular plants of the Florida Panhandle. Tallahassee, FL: Florida State University Press. 605 p. 
4. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. 
5. Ferriter, Amy, ed. 2001. Lygodium management plan for Florida: A report from the Florida Exotic Pest Plant Council's Lygodium Task Force. [Orlando, FL]: Florida Exotic Pest Plant Council. 51 p. 
6. Flores, Alfredo. 2005. Moth released to curb spread of climbing fern, [Online]. Washington, DC: U.S. Department of Agriculture, Agricultural Research Service (Producer). Available: http://www.ars.usda.gov/is/pr/2005/050214.htm? [2005, October 27]. 
7. Florida Exotic Pest Plant Council. 2005. List of Florida's invasive species, [Online]. Florida Exotic Pest Plant Council (Producer) Available: http://www.fleppc.org/list/05List.htm [2005, November 1]. 
8. Garland, Mark A. 2004. Noxious weed list: Plants in chapter 5B-57.007, Florida Administrative Code, [Online]. In: Noxious weed information. Florida Department of Agriculture and Consumer Services, Division of Plant Industry (Producer). Available: http://www.doacs.state.fl.us/pi/enpp/botany/images/noxiousweedtable1.pdf [2005, November 1]. 
9. Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; Lewis, Mont E.; Smith, Dixie R. 1977. Vegetation and environmental features of forest and range ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of Agriculture, Forest Service. 68 p. 
10. Goolsby, John A. 2004. Potential distribution of the invasive Old World climbing fern, Lygodium microphyllum in North and South America. Natural Areas Journal. 24(4): 351-353. 
11. Jones, Stanley D.; Wipff, Joseph K.; Montgomery, Paul M. 1997. Vascular plants of Texas. Austin, TX: University of Texas Press. 404 p. 
12. Jordan, Ramon. 2001. USDA plant hardiness zone map, [Online]. Washington, DC: U.S. Department of Agriculture, Agricultural Research Service, National Arboretum (Producer). Web version of: 1990 USDA plant hardiness zone map. Miscellaneous Publication No. 1475. Available: http://www.usna.usda.gov/Hardzone/ushzmap.html [2004, August 30]. 
13. Kartesz, John T. 1999. A synonymized checklist and atlas with biological attributes for the vascular flora of the United States, Canada, and Greenland. 1st ed. In: Kartesz, John T.; Meacham, Christopher A. Synthesis of the North American flora (Windows Version 1.0), [CD-ROM]. Chapel Hill, NC: North Carolina Botanical Garden (Producer). In cooperation with: The Nature Conservancy; U.S. Department of Agriculture, Natural Resources Conservation Service; U.S. Department of the Interior, Fish and Wildlife Service. 
14. Kuchler, A. W. 1964. United States [Potential natural vegetation of the conterminous United States]. Special Publication No. 36. New York: American Geographical Society. 1:3,168,000; colored. 
15. Langeland, Kenneth A. 2004. [Revised edition]. Natural area weeds: Old World climbing fern (Lygodium microphyllum). SS-AGR-21. Gainesville, FL: University of Florida, Institute of Food and Agricultural Sciences. 4 p. Available online: http://edis.ifas.ufl.edu/AG122 [2005, October 27]. 
16. Lott, Michael S.; Volin, John C.; Pemberton, Robert W.; Austin, Daniel F. 2003. The reproductive biology of the invasive ferns Lygodium microphyllum and L. japonicum (Schizaeaceae): implications for invasive potential. American Journal of Botany. 90(8): 1144-1152. 
17. McPherson, Guy R. 1995. The role of fire in the desert grasslands. In: McClaran, Mitchel P.; Van Devender, Thomas R., eds. The desert grassland. Tucson, AZ: The University of Arizona Press: 130-151. 
18. Mueller, Richard J. 1982. Shoot morphology of the climbing fern Lygodium (Schizaeaceae): general organography, leaf initiation, and branching. Botanical Gazette. 143(3): 319-330. 
19. Mueller, Richard J. 1983. Indeterminate growth and ramification of the climbing leaves of Lygodium japonicum (Schizaeaceae). American Journal of Botany. 70(5): 682-689. 
20. Myers, Ronald L. 2000. Fire in tropical and subtropical ecosystems. In: Brown, James K.; Smith, Jane Kapler, eds. Wildland fire in ecosystems: Effects of fire on flora. Gen. Tech. Rep. RMRS-GTR-42-vol. 2. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station: 161-173. 
21. Nauman, Clifton E.; Austin, Daniel F. 1978. Spread of the exotic fern Lygodium microphyllum in Florida. American Fern Journal. 68(3): 65-66. 
22. Paysen, Timothy E.; Ansley, R. James; Brown, James K.; Gottfried, Gerald J.; Haase, Sally M.; Harrington, Michael G.; Narog, Marcia G.; Sackett, Stephen S.; Wilson, Ruth C. 2000. Fire in western shrubland, woodland, and grassland ecosystems. In: Brown, James K.; Smith, Jane Kapler, eds. Wildland fire in ecosystems: Effects of fire on flora. Gen. Tech. Rep. RMRS-GTR-42-vol. 2. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station: 121-159. 
23. Pemberton, R. W.; Goolsby, J.A.; Wright, A. D. 2004. Old World climbing fern. In: Coombs, Eric M.; Clark, Janet K.; Piper, Gary L.; Cofrancesco, Alfred F., Jr., eds. Biological control of invasive plants in the United States. Corvallis, OR: Oregon State University Press: 447-448. 
24. Pemberton, Robert W. 1998. The potential of biological control to manage Old World climbing fern (Lygodium microphyllum), an invasive weed in Florida. American Fern Journal. 88(4): 176-182. 
25. Pemberton, Robert W.; Ferriter, Amy. 1998. Old World climbing fern (Lygodium microphyllum), a dangerous invasive weed in Florida. American Fern Journal. 88(4): 165-175. 
26. Punetha, N. 1987. Apical dominance and apical inhibition in the fronds of Lygodium japonicum (Thunb.) Sw. Phytomorphology. 37(4): 299-301. 
27. Radford, Albert E.; Ahles, Harry E.; Bell, C. Ritchie. 1968. Manual of the vascular flora of the Carolinas. Chapel Hill, NC: The University of North Carolina Press. 1183 p. 
28. Randall, John M. 1996. Lygodium japonicum--Japanese climbing fern. In: Randall, John M.; Marinelli, Janet, eds. Invasive plants: Weeds of the global garden. Handbook #149. Brooklyn, NY: Brooklyn Botanic Garden: 97. 
29. Raunkiaer, C. 1934. The life forms of plants and statistical plant geography. Oxford: Clarendon Press. 632 p. 
30. Roberts, Dick. 1997. Old World climbing fern research and mitigation at Jonathan Dickinson State Park. Resource Mangement Notes. Orlando, FL: Florida Department of Environmental Protection, Florida Park Service. 9(2): 30-32. 
31. Rosen, David J.; Jones, Stanley D.; Rettig, Virginia E. 2003. A floristic survey of Big Branch Marsh National Wildlife Refuge, St. Tammany Parish, Louisiana. SIDA. 20(3): 1189-1216. 
32. Shiflet, Thomas N., ed. 1994. Rangeland cover types of the United States. Denver, CO: Society for Range Management. 152 p. 
33. Snyder, James R.; Herndon, Alan; Robertson, William B., Jr. 1990. South Florida rockland. In: Myers, Ronald L.; Ewel, John J., eds. Ecosystems of Florida. Orlando, FL: University of Central Florida Press: 230-274. 
34. Stanturf, J. A.; Conner, W. H.; Gardiner, E. S.; Schweitzer, C. J.; Ezell, A. W. 2004. Recognizing and overcoming difficult site conditions for afforestation of bottomland hardwoods. Ecological Restoration. 22(3): 183-193. 
35. Stickney, Peter F. 1989. Seral origin of species comprising secondary plant succession in Northern Rocky Mountain forests. FEIS workshop: Postfire regeneration. Unpublished draft on file at: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory, Missoula, MT. 10 p. 
36. Stocker, Randall K.; Ferriter, Amy; Thayer, Dan; Rock, Michael; Smith, Steve. 1997. Old World climbing fern hitting South Florida below the belt. Wildland Weeds. (Winter): 6-10. 
37. U.S. Department of Agriculture, Natural Resources Conservation Service. 2011. PLANTS Database, [Online]. Available: https://plants.usda.gov /. 
38. Volin, John C.; Lott, Michael S.; Muss, Jordan D.; Owen, Dianne. 2004. Predicting rapid invasion of the Florida Everglades by Old World climbing fern (Lygodium microphyllum). Diversity and Distributions. 10(5-6): 439-446. 
39. Volin, John C.; Lott, Michael S.; Muss, Jordan D.; Owen, Dianne; Stewart, Joy. 2003. The physiological ecology of the non-indigenous invasive Lygodium microphyllum in South Florida. In: Abstracts--Invasive plants in natural and managed systems: linking science and management: Proceedings, 7th international conference on the ecology and management of alien plant invasions; 2003 November 3-7; Fort Lauderdale, FL. Lawrence, KS: Weed Science Society of America: 92. Abstract. 
40. Wade, Dale D.; Brock, Brent L.; Brose, Patrick H.; Grace, James B.; Hoch, Greg A.; Patterson, William A., III. 2000. Fire in eastern ecosystems. In: Brown, James K.; Smith, Jane Kapler, eds. Wildland fire in ecosystems: Effects of fire on flora. Gen. Tech. Rep. RMRS-GTR-42-vol. 2. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station: 53-96. 
41. Wood, Marcia. 2000. Global search for climbing fern's foes. Agricultural Research. 48(7): 16-18. 
42. Wunderlin, R. P.; Hansen, B. F. 2008. Atlas of Florida vascular plants, [Online]. In: PlantAtlas.org. Tampa, FL: University of South Florida, Institute for Systematic Botany (Producer). Available: http://www.florida.plantatlas.usf.edu/ [2009, October 15]. 
43. Wunderlin, Richard P. 1982. Guide to the vascular plants of central Florida. Tampa, FL: University Presses of Florida. 472 p. 
44. Wunderlin, Richard P. 1998. Guide to the vascular plants of Florida. Gainesville, FL: University Press of Florida. 806 p.