T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network


Thread fern (Blechnum filiforme)

Kingdom: Plantae
Division: Pteridophyta
Class: Pteridopsida
Order: Athyriales
Family: Blechnaceae
Genus: Blechnum L.
Species: B. filiforme
Binomial name: Blechnum filiforme
Common name: Thread fern, The Climbing fern, Panako

Blechnum filiforme is a species of fern in the hard fern family found in damp lowland forests. Blechnaceae. It is a creeping and climbing fern.
Juvenile plants creep over the ground before reaching a tree trunk and climbing upwards then developing larger sterile and fertile fronds. It spores are blown in the wind. It can regenerate vegetatively. The name thread fern refers to the adult thread like leaflets seen grown on tree trunks. In New Zealand B. filiforme is often associated with other fern understory species; an example of such an understory associate is Blechnum discolor.

Blechnum filiforme develops three distinct frond shapes while growing to an adult plant. It has one shape at ground level. It has another shape while climbing and the adult shape which has long graceful thread like leaflets. It is interesting to note that the rhizomes contain a sitosterol chemical which is the main ingredient in a propriety drug used to lower blood cholesterol. When sufficient height is achieved specialist fertile fronds bearing spores are produced.

Stage one growing on the ground.

Photo below is stage two (the climbing stage)

The climbing stage leaflets