Tree fern in the context of "Glasgow Botanic Gardens"

The Carboniferous rainforest collapse (CRC) was a minor extinction event that occurred around 305 million years ago in the Carboniferous period. The event occurred at the end of the Moscovian and continued into the early Kasimovian stages of the Pennsylvanian (Upper Carboniferous).

It altered the vast coal forests that covered the equatorial region of Euramerica (Europe and North America). This event may have fragmented the forests into isolated refugia or ecological "islands", which in turn encouraged dwarfism and, shortly after, extinction of many plant and animal species. Following the event, coal-forming tropical forests continued in large areas of the Earth, but their extent and composition were changed.

A cloud forest, also called a water forest, primas forest, or tropical montane cloud forest, is a generally tropical or subtropical, evergreen, montane, moist forest characterized by a persistent, frequent or seasonal low-level cloud cover, usually at the canopy level, formally described in the International Cloud Atlas (2017) as silvagenitus. Cloud forests often exhibit an abundance of mosses covering the ground and vegetation, in which case they are also referred to as mossy forests. Mossy forests usually develop on the saddles of mountains, where moisture introduced by settling clouds is more effectively retained.

Cloud forests are among the most biodiversity-rich biomes in the world, with a large number of species directly or indirectly depending on them.

Alsophila is a genus of tree ferns in the family Cyatheaceae. It has also been considered to be a section in the subgenus Cyathea of the genus Cyathea.

Dicksoniaceae is a group of tropical, subtropical and warm temperate ferns, treated as a family in the Pteridophyte Phylogeny Group classification of 2016 (PPG I), and counting 30-40 species. Alternatively, the family may be sunk into a very broadly defined family Cyatheaceae sensu lato as the subfamily Dicksonioideae. Most of the genera in the family are terrestrial ferns or have very short trunks compared to tree ferns of the family Cyatheaceae sensu stricto. However, some of the larger species can reach several metres in height. A number of others are epiphytes. They are found mostly in tropical regions in the Southern Hemisphere, as far south as southern New Zealand. Larger tree ferns in the genus Cibotium were formerly included in Dicksoniaceae, but are now segregated as the family Cibotiaceae.

Tempskya is an extinct genus of tree fern that lived during the Cretaceous period. Fossils have been found across both the Northern and Southern hemispheres. The growth habit of Tempskya was unlike that of any living fern or any other living plant, consisting of multiple conjoined dichotomous branching stems enmeshed within roots that formed a "false trunk".

Psaroniaceae is an extinct family of marattialean tree ferns from the Carboniferous–Permian interval. Most fossilized genera, species and spores of the order Marattiales may be placed in this family. Members of the family differ from Mesozoic and more recent tree ferns in the way the roots were produced, in the structure and organization of fronds and pinnules, and in dehiscence. Some sources merge the family into a much larger family, Asterothecaceae.

Fossil genera of the family include:

Tietea was a genus of marattialean tree ferns from the Late Carboniferous to the Permian. The genus has been placed in a number of families, including Psaroniaceae. The first described species was Tietea singularis, which grew up to 12 metres (39 ft) in height. It is estimated to represent close to 90% of some fossil assemblages in Brazil. Tietea derbyi was described in 1992, but its validity has been questioned as it could be a laterally flattened specimen of T. singularis.