Don’t rush to remove your rushes! Why rushes and sedges are good for wildlife

When rushes and sedges begin spreading across wet ground, it can feel as though a property is becoming overgrown. But Land for Wildlife Coordinator Phil Wise has found that these dense, tangled areas can provide important habitat for a remarkable range of Tasmanian wildlife.

What happens when you stop slashing

On my own Land for Wildlife property on the edge of Kunanyi, I stopped all slashing along the creekline that bisected the open land 18 years ago when I first moved there.

Even within that first summer, the first shoots of pale rush (Juncus pallidus) began appearing along the creekline, together with other pioneering species such as narrow-leaf fireweed (Senecio linearifolius). They were then joined by species including bat’s wing fern (Histiopteris incisa) and tall sedge (Carex appressa).

Before long, I had that thick, seemingly impenetrable habitat. With it came some pretty amazing wildlife-viewing opportunities.

The same thing happens in damp areas right across Tasmania. Rush and sedge species commonly grow along drainage lines and wetlands on previously open pastoral land. They are often among the first plants to regrow where grazing pressure has been reduced or slashing no longer occurs.

To many landholders, their spread can feel like the land is getting away from them. After all, it can happen quickly. Relatively open land can soon become a tangle of stems, a maze of tussocks and apparently impenetrable waist-high vegetation. But from the perspective of wildlife, this is far from undesirable.

Wildlife in the rushes

One of the first things I noticed were the white moths that appeared from the area during the warm months each year. I noticed them because my boys took great pleasure in trying to run through the rushes to flush them out so they could give chase.

When I looked them up, they turned out to be white rush moths, which rely on rushes for their life cycle. Their caterpillar and pupal stages are completed within the hollow rush stems. For me, seeing them is now a sign that warmer days are close. It also reminds me of more innocent times with my boys, before they started driving cars and discovering screens.

The moths are, of course, an important part of the food chain. Common froglets and brown tree frogs are more than happy to chow down on the adults, as are the bands of superb fairy-wrens that regularly pass through.

As the rushes thickened, I also noticed small tunnels forming through the vegetation. One day I was lucky enough to see a small swamp rat ducking out briefly into a sunny patch between tussocks. These sightings have become more common again recently.

What the camera revealed

When I set up my WildTracker camera for a month-long survey at what I call the ‘swamp site’, I received even more surprises about what was using the habitat.

The camera recorded eastern barred bandicoots, pademelons, long-nosed potoroos, eastern quolls and a beautiful firetail feeding on the Juncus seeds. Some of the Land for Wildlife folk I have visited have even seen burrowing crayfish on camera or while out walking through the reeds at night.

Several feral cats, brown rats, black rats and house mice also featured. This wasn’t overly surprising, as the camera was less than 50 metres from my chicken shed.

It did make me think about the impact I might be having on native rats by unintentionally encouraging introduced species into the area. That knowledge led me to reduce excess feed available to feral rodents by using raised feeders and being more measured about how much food I give to the chickens.

Returning to the landscape

The common genera of plants in these communities include Juncus, Lepidosperma, Carex, Baumea and Gahnia, along with many grasses and herbs. Of course, these plants are just returning to areas where they have grown for thousands of years.

My wonderful copy of Palawa tunapri by Trish Hodge points out the many important uses of these plants by the Tasmanian Aboriginal people, including food from the seeds, canoe building with hollow reeds, weaving and medicine.

Managing the challenges

There are certainly less desirable plant species that take advantage of the shelter provided by rushes and sedges. I am constantly trying to manage foxglove (Digitalis purpurea), Californian thistle (Cirsium arvense), Scotch thistle (Onopordum acanthium), blackberry (Rubus fruticosus aggregate) and other weeds that make their way in from surrounding properties. This is not easy among dense stems and damp ground.

In my experience, weed control works best when neighbours share similar goals. We have worked together towards reducing these weeds in my area for several years.

There are also a few practical considerations when managing this type of habitat:

• Keep dense vegetation away from houses and other assets to reduce fire risk.
• Consider the timing of slashing to avoid disturbing wildlife, including breeding swamp harriers between September and December.
• Be prepared for manual weed control, as many wetland areas are sensitive environments where chemical control may not be appropriate.
• Take steps to minimise food sources that attract feral rodents and other introduced species.

Worth protecting

Of course, it wouldn’t be Tasmania without our local turbo chooks – Tasmanian native hens – hiding their speckly eggs away in the rushes.

Something I look forward to each year is hearing the low-frequency, drum-like grunts of the adults among the sedges as they guide their little black fluff-ball chicks.

In my area, the chicks usually appear around July and then again around November. The parents are frequently seen carrying beaks full of worms into the rushes, helping their chicks to grow quickly before they can be taken from above. They face constant threats from the ever-watchful grey goshawk and the swamp harrier, which travels down this way to breed among the same rushes just in time for when these fluffy little snacks appear.

The moral of the story is that while rushes and sedges can sometimes feel like they are ‘taking over’, they are actually providing important habitat for a remarkable range of Tasmanian wildlife.

When you take the time to watch and listen, these wet areas reveal themselves to be some of the most wildlife-rich parts of a property.

For me, they are one of the many pleasures of living on a Land for Wildlife property.

Banner photo by Phil Wise.