Pilbara Plants: Hills alive with spinifex green

Many people have asked me about the changing hues on our Karratha hills lately from rust-red to velvety green.

The spinifex grass cover on our beautiful hills, is actually Triodia (from ancient Greek, Tri meaning three and odous meaning teeth referring to the three toothed glume of the flower) and is now in full recovery mode after the dry.

Spinifex plants grow in large clumps with many needle-like leaves giving the plant a hemispherical appearance and the landscape that iconic hummocky look.

During the first dry period the leaf blades become permanently folded, this means that only one side of the leaf is exposed to the hot dry air which reduces exposure and evaporation.

The leaf blades are rigid and have minute silicon granules, like microscopic bits of glass, embedded in them.

This deters predators – but sadly does not stop humans from smashing them with bikes or vehicles.

Once damaged they don’t recover! We have three types of Triodia on our hills – one soft or gummy spinifex (Triodia epactia) and two hard spinifex, T. angusta along creek lines and T. wiseana on the really stony crests.

The gummy spinifex, so called because to the thick resin on its leaves, grows on the slopes – you will smell its wonderful fragrance diffusing through the air after the first rains for the season.

The resin, which accumulates at the base of the plant and is harvested by termites for their nests, is prized by Aboriginal people who to this day use is as super-glue for mending purposes!

The green of the hills is just beginning to turn yellowish-green as the plants develop their flowers. Keep watching – as the seed heads develop the hills turn straw coloured before settling into winter dark green again.

We are blessed with stage show Mother Nature provides on the backdrop of our iconic Karratha hills.