Planting native grass to control mosquito borne disease

Yellow robin

Did you know that if you want to control mosquito borne disease it may help to plant native grasses? The reasoning as to why this might be so is a bit of a yarn. Bear with me.

Living near a river, mosquitoes are inevitable, but some times they are worse than others. And they are a worry, as mosquito-borne diseases like Ross River Fever and maybe even the sinister “Buruli ulcer” are becoming more common even in Melbourne.

Microbats, those little flutterers that are about the size of a mouse (“flittermice” is an old name), eat about half their body weight in insects every night. Including mosquitoes. Up to 500 insects an hour. But the bats need somewhere to hang out and sleep during the day, and this is typically in little crevices and hollows in old trees. Continue reading


Rainshadow plant communities: relictual or refugial?

Grassy woodland

Will dry-climate species spread from their current rainshadow niches, where they are a botanist’s curiosity item, to recolonise the surrounding, warming landscape? Are they waiting in these refuges for the opportunity, or merely relics on their way out?

Continue reading

Indigenous plants for a degraded site

Our local Friends group asked me to work out plant lists for autumn/winter plantings along the river. How to work out a plant list? With all the changes wrought since colonization, and further coming with climate change, what species are appropriate?

Once all of the plain at Bacchus marsh was some kind of redgum swamp, with billabongs, and rivers and streams frequently changing course across the floodplain. There’s still a billabong down at the Parwan end, near where the Werribee and Lerderderg rivers meet, but it’s on private land so most won’t have seen it.

In the section we planted on April 3, near the main Grant St bridge over the Werribee River, the river has been artificially deepened to prevent flooding. As the story goes, the farmers held title to the middle of the river, but the river kept moving so this caused some friction between landowners. At some point, they banded together and dug a deeper, permanent channel. Continue reading

Living on the edge

Moonah at Parwan Gorge

Where the volcanic plains were cut through by the river, just east of Bacchus Marsh at Parwan Gorge, giant blocks of weathered basalt tumble over the edge of a precipitous, wind-blasted escarpment.

A harsh environment, on the edge of the fertile plains, above the fertile river valley, but vastly different from either. In this peculiar niche a special community lives: the escarpment shrubland. Crowning it all is a row of ancient Moonah trees (Melaleuca lanceolata). Continue reading

5000 trees! Grow West planting at Rowsley

The annual planting day for Grow West was this Sunday. Grow West is an alliance of catchment, landcare and environmental groups engaged in revegetating areas of degraded farmland between Bacchus Marsh and Ballan. The main work is constructing a revegetated wildlife corridor linking key state parks.

The southern link crosses the Parwan Valley, to link the Brisbane Ranges park with Werribee Gorge state park. This year we were planting on the Lakeys’ property at the northern end of that corridor. Last year the planting day was at the other end of the Valley, on Yaloak Estate. Continue reading

DIY native grass lawn

Since the millenium drought, many gardeners and homeowners have had to reconsider the traditional Aussie suburban lawn. Or perhaps, if I remember my childhood accurately, have reverted to the more traditional version, which had patches of dust and dead grass through summers, and patches of ground as hard as concrete where it was well trodden — not soft emerald-green turf year-round. Perhaps it depends on where you grew up and how much you used the sprinkler.

Some have now renounced lawns completely. A waste of water! You could be growing vegetables there! Or, alternatively, why not astroturf it or concrete it? In the 1970s, white pebbles were fashionable as a rock mulch to replace lawns (they can look great, until a sea of weeds pops up between them).

Lawns have a legitimate function. You can sit on them and relax, the kids can play on them, the dog can sun itself, etc. They also keep your garden cool in the hot summer, unlike concrete and gravel and (ugh!) synthetic fake grass. And unlike concrete, they let the rain soak into the soil instead of creating a runoff/stormwater problem. And native animals may be attracted by them.

There’s no reason you have to have one, but since water-wise native lawns are possible, you don’t need to feel guilty for allocating some lawn space, even in the midst of water restrictions and drought. Continue reading