Adiantum silvaticum

Rough Maidenhair, Forest Maidenhair Fern

Family: Pteridaceae

This ferm is a comparatively taller maidenhair fern growing in rainforest or open eucalyptus forests, often along streams and moist cliff faces; north from the Illawarra region along the coast in NSW, extending west into the and ranges and into Queensland.

Rhizomes are long and creeping, usually on the soil surface.

Erect fronds grow to 80cm high, with fronds considered compound-pinnate, and are bipinnate (Jacaranda-type) or tripinnate (divided again). Hence, the foliage consists of branched portions of frond within a larger frond, made up of segments (pinnules or leaflets). The segments (pinnules/leaflets) are to 20 mm long, pale to dark green long and to 5-7 mm wide, roughly rectangular, asymmetrical or egg-shaped. The main frond stem can also have a zig-zag formation.

Being a fern, no flowers or fruits are produced.

Spores are produced in sporangia, which are housed in a sorus (plural sori). The sori are produced on the underside of frond segments and follow the segment edges. There can be 5 sori per segment.

In the garden

It is not fast-growing, but will eventually make a clump if given the right conditions. It needs good light to fairly deep shade, and it should be kept moist for optimum growth although it is quite hardy.

An interesting feature of this plant is the colour of the new growth. The tiny pinnules on new fronds are almost black, becoming deep purple as the pinnules develop a little, then a breath-taking pink as the frond reaches its full spread.

Scale can be a problem and Maidenhair aphids.

Is listed for sale on Ebay at time of writing (see references), so likely has some cultivation potential.

Propagation

Propagation is from plant division or by spores.

Other information

Lives in habitats not prone to fire. Response to fire unknown.

Adiantum – from the Greek adianton (ἀδίαντον) meaning “not wetting” or “un-wet-table”, referring to the fronds’ ability to shed water without becoming wet, likely due to the waxy surface of the segments.
silvaticum – Latin pertaining to trees or forests (silviculture), basically referring to the habitat of the species.

Not considered at risk in the wild.

https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Adiantum~silvaticum
A.N.P.S.A. Fern Study Group Newsletter Number 135 dated February 2016
http://www.anpsa.org.au/fernSG/fern135.pdf
https://www.ebay.com.au/itm/Fern-spore-Adiantum-silvaticum-Mountain-Maidenhair-Fern-/224157441640

By Jeff Howes