According to a Chinese proverb, the best time to plant a tree was twenty years ago, and the next best time is now. Here at the Danthonia Bruderhof, we’re working to make up for lost time. Since 2007, we’ve planted upwards of fifty thousand trees across 160 hectares of our New South Wales farm.
Recent weather cycles haven’t been supportive. We started six years into Australia’s “millennium drought” (2001 to 2009), planting a mix of native and exotic species – eucalypts, she-oaks, tea trees, common alder, nettle tree, red and white ash – in wind-breaking beltways twenty-five meters wide looping along ridge tops. When no rain came, we watered what trees we could, and watched others die. There followed two wet years when farms and towns in our area battled floods, and then since early 2012 we’ve been sliding back into drought. Despite our best efforts, we’ve lost about a third of the trees we’ve planted. Still, we replant, tend, and water – and accept the truth that only God can make a tree.
After all, this is the Australian bush, touted by its oft-quoted poet Dorothea Mackellar as a land “of droughts and flooding rains.” Caveat agricola – farm at your own risk. Around here, you can do the math on your fingers: in a ten-year span, expect two bumper years, three average, and five subpar to poor years. That’s if all goes well. Like most farms in the Australian bush, ours has endured generations of sheep and cattle chomping vegetation down to the roots and trampling the frangible soil into dusty moonscapes. The old-timers will tell you they had no choice. You farmed with one eye on the weather and the other on the bank, made your money when the rain came, and flogged the land when it didn’t – nothing that a crop-duster and a load of superphosphates couldn’t fix up.
The result has been rapid and widespread decline in soil health as erosion, salinization, acidification, and other maladies exact a heavy toll in lost agricultural productivity and revenue.1 The process began less than two hundred years ago, when European settlers began clearing the land and brought in non-native livestock. A 2010 report by Australia’s national science agency concluded that the soil organic carbon stocks on agricultural land is forty to sixty percent lower than when the land was cleared.2 That degradation could be as high as eighty percent, according to Dr. Christine Jones, founder of the Australian Soil Carbon Accreditation Scheme.
That’s why for us at Danthonia, planting trees isn’t just about beautifying our land; it’s about ensuring that there will be land worth passing on to the next generation, land healthy enough to withstand the vagaries of an unforgiving and ever-changing climate. While there’s no such thing as drought-proof farming, there are field-tested ways to better the odds. Planting trees is one of them – and of course, soil is where it starts.
Some may see preserving soil carbon as a noble ecological cause or a profitable business move, but for us it’s more basic: more soil carbon equals more water retention. For a hectare of land with a soil depth of thirty centimeters, increasing carbon levels by just one percent enables the soil to retain an added 160,000 liters of water.3 In an eight-year drought, that can determine whether a farm survives.
Trees improve soil carbon by contributing organic matter throughout their lifecycle, as roots, leaves, bark, flowers, and fruit grow and then die and rot. But their real importance comes from the microclimate they help create. Already the trees we planted seven years ago stand higher than a man. The shaded grass around them is lush, and the paddocks on the leeward side of the plantings look healthier, proving the rule that a pasture’s fertility is improved to a distance four times the height of the trees. Since grasses are the champions in soil-carbon production, a virtuous cycle is beginning, with healthier soil retaining more water and so supporting more biomass, which in turn will add even more soil carbon.
There are other benefits too. The tree beltways are wildlife corridors that swarm with insects and birds. In four years of recordkeeping, we’ve marked a twenty-seven percent surge in bird species sighted.
Trees may save our land – at least if everything works as we hope. No doubt the Australian climate still has a few surprises in store for us. In the meantime, our trees teach us to take the long view, to willingly sweat for the benefit of children yet to be born, to celebrate incremental victories, to mark the miracle that is all growing things. We plant them, tend them, and trust they are harbingers of better days to come.
Footnotes
- Jonathan Sanderman, Ryan Farquharson, and Jeffrey Baldock, Soil Carbon Sequestration Potential: A review for Australian agriculture, CSIRO Land and Water, 2010.
- The value of lost agricultural production due to soil acidification alone has been estimated at $ 1.6 billion AUD per year. State of the Environment 2011 Committee, Australia State of the Environment 2011, Australian Government Department of Environment, 2011.
- Our neighbor Glenn compiled recent studies in Glenn David Morris, “Sustaining National Water Supplies by Understanding the Dynamic Capacity that Humus Has to Increase Soil Water,” thesis submitted for Master of Sustainable Agriculture, University of Sydney, July 2004.