Tree ferns are found growing in tropical and subtropical areas, including cool to temperate rainforests in Australia, New Zealand, Malaysia, Lord Howe Island. Like all ferns, tree ferns reproduce by means of spores developed in sporangia on the undersides of the fronds.

The fronds of tree ferns are usually very large and multiple-pinnate but at least one type has entire (undivided) fronds. The fronds of tree ferns also exhibit circinate vernation, meaning the young fronds emerge in coils that uncurl as they grow. Unlike flowering plants, tree ferns do not form new woody tissue in their trunk as they grow. Rather, the trunk is supported by a fibrous mass of roots that expands as the tree fern grows.