Tree fern ecology in New Zealand

Summarizing 100 years of published and unpublished data on the ecology and biogeography of tree ferns in New Zealand.

GBIF-mediated data resources used : 28,343 species occurrences
Rough tree fern (Dicksonia squarrosa)

Rough tree fern (Dicksonia squarrosa) in Pohangina Valley, NZ. Photo by Leon Perrie via NatureWatchNZ licensed under CC BY-NC 4.0.

Tree ferns are a clade of leptosporangiate ferns with trunk-like structures in the order Cyatheales. In New Zealand, tree ferns have been a widespread and significant component of the forest ecosystems since the Paleocene epoch.  Although not a major player in modern forestry, tree ferns are harvested in vast numbers to service the international ornamental market. This paper provides an overview of New Zealand tree fern ecology and its role in forest community dynamics, in part informed by GBIF-mediated occurrences. Prominent in early forest communities after disturbances, tree ferns are limited in gamete and spore production by irradiance and nutrient levels, but may persist for more than 250 years. The main predictor of tree fern abundance is total soil phosphorus, and the key drivers of species diversity is mean temperature and solar radiation. In regenerating forest communities, tree ferns can play a major role in suppressing canopy angiosperms and conifers.

Brock JMR, Perry GLW, Lee WG and Burns BR (2016) Tree fern ecology in New Zealand: A model for southern temperate rainforests. Forest Ecology and Management. Elsevier BV 375: 112–126. Available at doi:10.1016/j.foreco.2016.05.030,