Fern ally is a general term covering a somewhat diverse group of vascular plants that are not flowering plants (angiosperms) and not true ferns. Like ferns, these plants reproduce by shedding spores to initiate an alternation of generations. There are three or four groups of plants considered to be fern allies. In various classification schemes, these may be grouped as classes or divisions within the plant kingdom. The more traditional classification scheme is as follows (here, the first three classes are the "fern allies"):

  • Kingdom: Plantare
    • Division Tracheophyta (vascular plants)
      • Class Lycopsida, (fern-allies) the clubmosses and related plants
      • Class Sphenopsida or Equisetopsida, (fern-allies) the horsetails and scouring-rushes
      • Class Psilopsida, (fern-allies) the whisk ferns
      • Class Filices, the true ferns
      • Class Spermatopsida (or sometimes as several different classes of seed-bearing plants)

A more modern or newer classification scheme is:

  • Kingdom Plantare
    Subkingdom Tracheobionta
    • Division Lycopodiophyta
      • Class Lycopodiopsida, the clubmosses
      • Class Selaginellopsida, the spikemosses
      • Class Isoetopsida, the quillworts
    • Division Equisetophyta, the horsetails and scouring-rushes
    • Division Psilotophyta, the whisk ferns
    • Division Ophioglossophyta, the adders'-tongues and moonworts
    • Division Pteridophyta, the ferns
    • Division Spermatophyta (or as several different divisions of seed-bearing plants)

Note that in either scheme, the basic subdivision of the fern allies is preserved, with the exception that the Ophioglossophyta (Ophioglossopsida), once thought to be true ferns, are now generally regarded by many to be a distinct group of fern allies.

Economic uses

Ferns are not of major, direct economic importance, with one possible exception. Ferns of the genus Azolla, which are very small, floating plants that do not look like ferns, called mosquito fern, are used as a biological fertilizer in the rice paddies of southeast Asia, taking advantage of their ability to fix nitrogen from the air into compounds that can then be used by other plants.

Other ferns with some economic significance include:

  • Dryopteris filix-mas (male fern), used as a vermifuge
  • Rumohra adiantoides (floral fern), extensively used in the florist trade
  • Osmunda regalis (royal fern) and Osmunda cinnamomea (cinnamon fern), the root fiber being used horticulturally; the fiddleheads of O. cinnamomea are also used as a cooked vegetable
  • Matteuccia struthiopteris (ostrich fern), the fiddleheads used as a cooked vegetable in North America
  • Pteridium aquilinum (bracken), the fiddleheads used as a cooked vegetable in Japan
  • Diplazium esculentum (vegetable fern), a source of food for some native societies
  • Pteris vittata (Brake fern), used to absorb arsenic from the soil
  • Tree ferns, used as building material in some tropical areas

Ferns have additional value in various cultures in terms of use for food, fiber (stuffing pillows, etc.), and in building material (Croft 1999). Ferns also provide aesthetic value, whether from their beauty in the wild or there use in landscaping, crafts, paintings, and decorations. May (1978) listed 150 different uses of ferns and fern allies.

In some cases, ferns provide negative value, such as in their role as weeds in agriculture.

Misunderstood names

Several non-fern plants are called "ferns" and are sometimes popularly believed to be ferns in error. These include:

  • "Asparagus fern" - This may apply to one of several species of the monocot genus Asparagus, which are flowering plants. A better name would be "fern asparagus."
  • "Sweetfern" - This is a shrub of the genus Comptonia.
  • "Air fern" - This is an unrelated aquatic animal that is related to a coral; it is harvested, dried, dyed green, then sold as a plant that can "live on air." It looks like a fern but is actually a skeleton.

In addition, the book Where the Red Fern Grows has elicited many questions about the mythical "red fern" named in the book. There is no such known plant, although there has been speculation that the Oblique grape-fern, Sceptridium dissectum, could be referred to here, because it is known to appear on disturbed sites and its fronds may redden over the winter.

Gallery of ferns

  • Fern leaf, probably Blechnum nudum

  • A tree fern unrolling a new frond

  • Tree fern, probably Dicksonia antarctica

  • Tree ferns, probably Dicksonia antarctica


  • May, L. W. 1978. "The economic uses and associated folklore of ferns and fern allies." Bot. Rev. 44: 491-528.
  • Moran, R. C. 2004. A Natural History of Ferns. Portland, OR: Timber Press. ISBN 0881926671.
  • Pryer, K. M., E. Schuettpelz, P. G. Wolf, H. Schneider, A.R. Smith, and R. Cranfeld. 2004. "Phylogeny and evolution of ferns (Monilophytes) with a focus on the early Leptosporangiate divergences." American Journal of Botany 91:1582-1598.
  • Pryer, K. M., H. Schneider, A. R. Smith, R. Cranfill, P. G. Wolf, J. S. Hunt, and S. D. Sipes. 2001. "Horsetails and ferns are a monophyletic group and the closest living relatives to seed plants." Nature 409: 618-622 (abstract here).Retrieved November 29, 2007.
  • Pryer, K. M., E. Schuettpelz, P. G. Wolf, H. Schneider, A. R. Smith, and R. Cranfill. 2004. "Phylogeny and evolution of ferns (monilophytes) with a focus on the early leptosporangiate divergences." American Journal of Botany 91:1582-1598 (online abstract here).Retrieved November 29, 2007.

External links

All links retrieved April 6, 2017.

  • Croft, J. 1999. Checklist of World Ferns.
  • Hassler, M., and B. Swale. 2001. Checklist of Ferns and Fern Allies.
  • Knouse, J. A. Bibliography of Major Pteriodological Works.