Ferns and Fern Allies in the Canberra Region

Blechnum wattsii - Hard Water Fern

Blechnum wattsii is one of three water ferns that grow in great profusion in permanently damp areas in and near mountain creeks in the region. It will often be found growing among colonies of B. minus (Soft Water Fern) and B. nudum (Fishbone Water Fern). It seems to like shadier areas than B. nudum and tends to grow as individual specimens rather than in large colonies. Its pinnae are coarse and leathery with finely serrated margins. The fertile fronds are the same size as the sterile ones, but the pinnae are much narrower. At a distance it looks somewhat like individual plants of B.minus but its first two pinnae are long and set at around 45° to the rhachis (stalk), a little like rabbit or bat-ears. Its pinnae are considerably wider than those of B. minus and B. nudum - fronds of the latter can be see in the top right corner of this picture (deeper green, in the shade).

A single frond showing the "bat ears" appearance of the initial pinnae. The pinnae are typically 2cm (3/4") across and the fronds can be up to 1 metre tall.

An unusual fertile frond that converts from sterile to fertile half way up.

David Nicholls
January 1998