[clarification needed] Some genera — for example Dicksonia and Cibotium, and some Cyathea — can be transplanted by severing the top portion from the rest of the trunk and replanting it.

But other clump-forming tree fern species, such as D. squarrosa and D. youngiae, can regenerate from basal offsets or from "pups" emerging along the surviving trunk length.

[5] The linear sequence of Christenhusz et al. (2011), intended for compatibility with the classification of Chase and Reveal (2009)[6] which placed all land plants in Equisetopsida,[7] reclassified Smith's Polypodiopsida as subclass Polypodiidae and placed the Cyatheales there.

[6] The classification of Christenhusz and Chase (2014) placed all members of the Cyatheales in a more broadly defined Cyatheaeaceae, reducing the eight existing families to subfamilies as Thyrsopteridoideae, Loxsomatoideae, Culcitoideae, Plagiogyrioideae, Cibotioideae, Cyatheoideae, Dicksonioideae, and Metaxyoideae.

Historically, the Plagiogyriaceae were considered the single member of order Plagiogyriales, thought to be more closely related to Osmundales than to the tree ferns, but this hypothesis has been disproven by molecular phylogenetics.

Thyrsopteridaceae Loxsomataceae Culcitaceae Plagiogyriaceae Cyatheaceae Cibotiaceae Dicksoniaceae Metaxyaceae Thyrsopteridaceae Loxsomataceae Culcitaceae Plagiogyriaceae Metaxyaceae Cibotiaceae Dicksoniaceae Cyatheaceae Tree ferns are found growing in tropical and subtropical areas, as well as temperate rainforests in South Africa, Australia, Spain, Portugal, New Zealand, and other island groups nearby; a few genera extend further, such as Culcita in southern Europe.

[citation needed] Where feral pigs are a problem, as in some Hawaiian rainforests, they will knock over tree ferns to root out the starchy pith, killing the plant.