Ferns and Fern Allies in the Canberra Region

Blechnum nudum - Fishbone Water Fern

Blechnum nudum is by far the most common fern in fern gullies and boggy patches in mountain creeks in the region. It is one of three common water ferns that grow in these areas, often accompanied by B. minus (Soft Water Fern) and B. wattsii (Hard Water Fern). It may grow as individual plants but more often grows in large colonies, to the exclusion of any other fern except tree ferns. The fronds grow in a rosette from an erect rhizome which can form a short tree-fern-like trunk in old plants (see below). habitThe fronds can grow up to a metre long in this area. The pinnae are fairly coarse, though softer than those of its cousins, B. minus and B. wattsii, with narrower pinnae, usually no more than 1.2cm (1/2") wide. This picture shows a plant with a rosette of sterile fronds surrounding newly emerging fertile fronds. The fertile fronds are shorter than the sterile ones and the pinnae are much narrower. It is an attractive fern, very easy to grow, and extremely hardy, tolerating both heavy frost and some direct sun. It does best when its roots are permanently wet.

old plant showing trunkThe image at left shows a mature B. nudum plant growing in a Dicksonia antarctica grove in the Blue Range. It shows the treefern-like trunk, around 0.5m (20") high. Most mature specimens show this behaviour, though it is usually not obvious due to the accumulated debris of old dead fronds.

back site mapDavid Nicholls
January 1998