For 20 years, peter corish has been growing cotton in the black soil of southern Queensland. For most of that time, clearing his land to plant more crops was an unremarkable part of the job, one for which he needed no permission. All it took were a couple of bulldozers, first to drag a chain between them through the scrub and then to rake up the trees they had toppled. Most other freehold farmers in Queensland worked the same way. The clearing cost about $A150 a hectare.
Farmers like Corish were not only free to clear their land, they were often encouraged to do so by tax breaks or required to do so by the terms of their lease. Those who cleared to boost productivity, Corish says, were seen as "doing something that benefited not only themselves but the community." Not any more. The role of land clearing in salinization and the endangerment of many native flora and fauna species means this basic farming tool is increasingly seen as a grave threat to Australia's environment. Deciding what that means for the future of Australian agriculture is proving just as difficult as deciding what to do about the damage that clearing has already done. "Land clearing is the No. 1 issue for us," says Michael Wells, a beef grower from central Queensland, "because it's going to have the greatest effect on our ability to produce."
The clearing of Australia has been extensive. Landcare, the community-based movement leading revegetation efforts, estimated in 1999 that 20 billion trees had been cut down since European settlement. A landmark report by the Bureau of Rural Sciences found that between 1983 and '93, an average of 600,000 hectares of Australia's native bush were destroyed every year. Figures released this month-compiled from state government agency reports by the Australian Conservation Foundation-ranked Australia as the world's sixth largest land clearer, after Brazil, Indonesia, Sudan, Zambia and Mexico.
This is despite warnings by experts such as Denis Saunders, chief research scientist of the csiro's Sustainable Ecosystems division, who describes the consequences of land clearing as "the biggest environmental threat facing this country." Chief among those effects is salinization, which occurs when the removal of trees (whose roots drain water from lower layers of soil) causes water tables to rise, bringing salt stored in the soil toward the surface.
The days of unregulated clearing across the country are largely gone-most states introduced controls in the 1980s and '90s -but salinity can appear decades after land has been cleared, and it is now a national calamity-and getting worse. The issue has been plagued by a lack of Australia-wide data, but figures from the first National Land and Water Resources Audit, released last week, show that dry-land salinity (the type not caused by irrigation systems) now affects, or threatens, about 5.7 million ha of pastoral and agricultural land, as well as 630,000 ha of bush, most of it on agricultural land.
Fewer trees and saltier waterways also lead to species extinction-in the 16-million-ha West Australian wheat belt (11% of which is already afflicted by salinity), 450 species of native plants and around 80 species of birds are at risk of extinction. That high clearing rates persist is "extraordinary," says Saunders. "We can say precisely what the ecological and productivity consequences of broadscale land clearing will be in the long term-and yet clearing continues."
However belatedly, the message is getting through. Queensland, which in recent years has been clearing more land than any other state, introduced a permit system for freehold land clearing last September. Larry Acton, president of the state's AgForce rural lobby group, says farmers there now acknowledge that, given Queensland's relative lack of development, "we need to learn from the mistakes of the southern states." But although farmers are worried by salinity, they're frustrated, Acton says, by the claim that all their clearing is of virgin bush-when, in fact, "some of it is regrowth."
Farmers are also angered by the still unresolved issue of compensation for those barred by the new state laws from clearing environmentally important parts of their properties. (The Queensland and Federal governments are still arguing over who'll foot the bill.) "If our need for compensation isn't recognized," says cotton grower Corish, "the rural voting community will make their thoughts pretty obvious." Tackling salinity and loss of biodiversity are national burdens, says Acton, "and we should not have to carry the full economic cost."
Trying to counter the damage already done are groups like Landcare, which includes thousands of landholders: by 1995 they had planted 550 million trees. Landcare's other great success, says John Williams, deputy chief of csiro's Land and Water division, has been to create "a cadre of people ready to make change." Now, he says, "they need industries to move into and make money."
These are emerging in places like Western Australia, where one project is replanting native oil mallees on a vast scale to harvest their oil for industrial use. In Merredin, a town of 4,000 in W.A.'s wheat belt, pumping will soon begin of the saline groundwater eroding the town's foundations. It's hoped that one day the water will support aquaculture or be used for electricity generation. "Our approach is: We've got this resource, let's use it," says Doug Abrecht, head of W.A.'s Dryland Research Institute.
Others are trying to make a living growing trees rather than removing them. When Nicole and Ben Phillips bought a grazing property at Hattonvale, in southeast Queensland, two and a half years ago, they planned just to run cattle. Instead they're combining grazing with selective commercial logging of the native trees that still cover more than half their land. "Instead of looking at the trees as a liability, we realized they were a valuable resource and that we could have cattle and timber together," says Nicole.
The couple will log small numbers while replanting other areas to prevent further degradation. Says Nicole: "There's something extremely satisfying about walking through the forested parts, seeing different vegetation and wildlife, and knowing that with minimal effort on your part, you can maintain those areas and have an income from them at the same time." She describes the timber as their "superannuation policy." The health and comfort of the nation in its old age may depend just as crucially on trees.