Monday, 26 September 2016

In flood or drought, the ferns are here to stay

Much of eastern Australia is having a fairly wet spring this year, and the plant life seems to be thriving as a result!

Last week, I drove out to a tiny bushland reserve in the Ipswich suburb of Woodend to scout out some particular plants, namely ferns.

The reserve is accessed by a pathway that begins near the corner of Macrae and Ladley Street, and appears on Google Maps as Smith Park.

It protects a small gully that feeds into the Bremer River nearby.

I found two interesting ferns here, each adapted to a specific microhabitat within the reserve.

Mulga ferns, INSET: spores on frond underside, Woodend.

The first was the mulga fern (Cheilanthes sieberi), a tough little species found throughout much of Australia, including the outback.

It can make do with very shallow soils and extremely long periods without rain; combine that with the fact that it is quite toxic to grazing animals and it starts to become clear how ferns have survived on this planet for 360 million years!

At Smith Park, the mulga ferns grow on the rock ledges at the top of the gully, looking fairly inconspicuous among the grasses and weeds.

Binung, Woodend.

The second fern I found was the binung (Christella dentata), a lush, moisture-loving species that grows immediately alongside the water, in the depths of the gully.

It can be told apart from the similar ferns in the Blechnum genus by the toothed margins on its fronds, referred to in the scientific species name ‘dentata’.

A beautiful feature of our east coast waterways, the binung has nevertheless wreaked havoc as an introduced species on the Hawaiian islands, because it cross-breeds with a native fern to produce sterile offspring.

At Smith Park, the most troublesome weed resembles a fern, but is infact a member of the flowering plant family despite its name—the climbing asparagus fern (Asparagus africanus).

Unfortunately, it too appears to have thrived with the recent rain, so here’s hoping the local bushcare group are able to sort it out.

2 comments:

  1. Wet winter and spring here in Tassie. Ferns are always interesting. There is so much variety. In Scotland I remember seeing tiny ferns growing on sandstone cliffs by the sea.

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    1. You would have some outstanding ferns in Tassie, I bet! Lush forests of them! Glad there's another pteridophile out there :)

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