The Tasmanian tree fern is the most commonly grown tree fern in the Northern hemisphere. This Australian tree fern came into the UK at the end of the 20th Century aboard ships returning from Australia.
The ships carrying goods back from the colonies used tree fern trunks as ballast or weights in their holds to prevent cargoes moving about in heavy seas. At docks around the South West of England the trunks were discarded on the quayside when ships were unloaded. It was here that people noticed these trunks were growing new fronds and that, in time, the ends of the trunks were turning upwards and starting to re-grow towards the light.
Nowadays when the Tasmanian tree ferns is exported it is sawn of top and bottom just leaving the trunk in the same way as the first ships did, however today the trunks turn up at your local garden centre and their not cheap! Some of the oldest tree ferns in the UK can still be found at gardens such as Trewidden and The Lost Gardens of Heligan.
The Tasmanian tree fern – Dicksonia antarctica is one of 25 species in the Dicksonia genus. With only 25 species the Dickosnia family is very small compared to the Cyathea family which has over 500 species. The Dicksonia family includes some of the most important and now widely cultivated tree ferns in Europe and North America.
Dicksonia and Cyathea species are related, although Dicksonia is considered to be more primitive, dating back at least to the Jurassic and Cretaceous periods. The species can be distinguished in several ways firstly the fronds are usually coarser and look less waxy; secondly the croziers (uncurling fronds) are covered in fine hairs rather than scales. The individual fronds are more convex as opposed to the often flat fronds of many Cyathea species.
The Dicksonia family is named in honour of James Dickson (1738-1822), who was a prominent British nurseryman. It’s thought the link between James Dickson and tree ferns came from his friendship with Sir Joseph Banks (1743 –1820) who took part in Captain James Cook’s first great voyage ‘Endeavour ‘ (1768–1771). Sir Joseph Banks was known to have collected spores of Dicksonia arborescens in St. Helena during the ‘Endeavour’ voyage. However it was French botanist Charles-Louis L’Héritier (1746-1800) who first described and named the genus Dicksonia in Sertum Anglicum 1788. So the exact link between James Dickson and the tree ferns is unclear.
The name ‘antarctica’ comes from the species relative ‘southern’ location, or the relative proximity of the tree fern to the cooler climates of Antarctic regions as opposed to many tree ferns from warmer climates. The Tasmanian tree fern of course does not grow in Antarctic. The climate of Antarctica does not allow extensive vegetation. A combination of freezing temperatures, poor soil quality, lack of moisture, and lack of sunlight inhibit plant growth. As a result of this, plant life is limited to mostly mosses and liverworts. There is also no fossilized evidence that the species has ever been present on the Antarctic land mass.