For years, Mr Arnold says, he has been “bashing my head against the wall like a silly old goat” trying to persuade people of the merits of using goats to restore habitats. Organisations were reluctant because goats had a reputation for being hard to handle and expensive. Colin Arnold with one of his goats in Vermont this week. Credit:Penny Stephens “I have been trying to prove for the last 15 years that if managed properly goats are easy to work with and can be quite selective in what they eat,” Mr Arnold says. And then in 2015, the International Agency for Research on Cancer classified glyphosate – the active ingredient in many herbicides including Roundup – as “probably carcinogenic to humans”.

Loading This is controversial. Many regulatory bodies – including the Australian Pesticides and Veterinary Medicines Authority – say glyphosate can continue to be used safely according to label directions. However Australian farmer Ross Wild is among a group of litigants who are suing German pharmaceutical giant Bayer in the Victorian Supreme Court over claims that long-term exposure to Roundup caused their non-Hodgkin’s lymphoma. “Organisations are going ‘maybe we should look elsewhere’,” Mr Arnold says. “It’s only been in the last two years that people have been contacting me.” Mr Arnold’s herd of goats clear people’s backyards. But goats have also been deployed by councils and government authorities, including Knox, Whitehorse, Yarra Ranges, Maroondah, Metro Trains, Melbourne Water and EastLink, particularly on inaccessible, or sensitive sites, such as waterways.

On a blistering morning last week, a herd of goats were hard at work on a fenced-off patch of land at Abbey Walk in Vermont. Whitehorse Council’s general manager of infrastructure, Nigel Brown, says the land had remnant areas of native vegetation but was being smothered in a blanket of environmental weeds. “Council looked at ways to remove the environmental weeds but retain native vegetation in the parkland,” Mr Brown says. “The goats were considered an appropriate method of weed control as they will constantly chew on the weeds to the point they either die completely or weaken to the point that the native vegetation can grow back.”

It’s a bucolic scene. Painted lady butterflies flutter among native grasses, where they lay their eggs, while the goats munch on pasture grass, which is a weed here, and gorse, a prickly, invasive pest which many herbicides do not effectively kill. “They eat the exotic pasture grass, which is their chocolate, and leave the natives,” Mr Arnold says. Goats will eat almost anything - but tend to leave native vegetation. Credit:Penny Stephens By contrast, herbicide kills both native and exotic grasses. Mr Arnold fondles a goat’s ears. It’s relaxed and docile: “I tether them along my driveway so they don’t freak out when a car goes past.”

He shows us a nearby site, which still has native grasses, despite the fact Mr Arnold says it has been managed by goats for eight years. “People said: ‘You can’t put goats here, they will ruin it, but they clearly don’t eat everything ,” Mr Arnold says. He is discerning when matching goats to jobs; “the big goats are like bulldozers, they are effective on two-metre high blackberries and young goats do this kind of conservation stuff”. Whitehorse Council says the trial has been very successful with many serious weeds either removed completely or reduced significantly. “Much of the native vegetation is now growing back,” Mr Brown says.

Based on the trial’s success, the council is continuing to use goats at Abbey Walk and considering them for other sites. The results of another trial were more equivocal. Between 2015 and 2018, Melbourne Water compared the results of goat grazing with using herbicide at two sites at Dandenong Creek in Vermont South. An evaluation by Ecological Perspective found goat grazing was less effective and more expensive. “Factors that appeared to impede effective goat control included access to plants (ie plant height) and the wetness of the ground (goats avoided getting their feet wet),” the report prepared for Melbourne Water found.

It also found the goats did not kill blackberries and honeysuckle, something Mr Arnold disputes, and targeted both exotic and native species indiscriminately. Mr Arnold says there are some weeds goats don’t eat. “Goats work well as part of an integrated system where chemical use is minimised.” But Knox Council found goat grazing had “countless benefits”. The council used goats to help it rehabilitate Quarry Reserve in Upper Ferntree Gully, a former quarry which has been turned into a park. It says the goats were quiet, efficient, cost effective and their use meant no harmful chemicals or stressful burning-off was required.

Loading “It was a very steep and dangerous site. It was not really possible to get people to work there but the goats seem very at home,” says the council’s director of engineering and infrastructure Dr Ian Bell. “We were very impressed. They worked the areas they were supposed to and tended to focus on weeds as opposed to the good plants we were trying to retain.” The goats have been invited back next year to tackle an area above the quarry face where work previously hasn’t been possible because it would require harnesses and specialist qualifications to be accessed by humans. Victoria is not alone. Google famously hired 200 goats and a border collie to “mow” the lawn at its Googleplex headquarters in California, “hooved pros” are deployed in New York parks, and goats are used to rid the shores of Lake Burley Griffin in Canberra of noxious weeds.

“Everybody hates spraying chemicals, this is about another weapon in the arsenal,” Mr Arnold says. "I am not going to get non-Hodgkin’s lymphoma from handling goats.”