NZ orchardists aim for carbon neutrality
A New Zealand report says food miles are too simplistic and not a good measure of environmental impact.
The New Zealand apple industry, which exports more than 80 percent of its crop, is trying to turn attention from the long distance it ships the fruit to the low-input methods used to produce it.
Last year, researchers at Lincoln University in New Zealand issued a report in which they concluded that "food miles" was too simplistic a concept. To consider only the distance food travels was spurious, they said, as it did not consider the energy used in production.
The report compares the energy use and carbon dioxide emissions associated with producing agricultural products in New Zealand and in Europe. In the case of apples, the researchers found that producing apples in New Zealand was more energy efficient, despite the longer distance they were shipped to market. A big factor was yield efficiency, with the average yield in New Zealand estimated at 50 tons per hectare (equivalent to 50 bins per acre) compared with only 14 tons per hectare in the United Kingdom.
Earnscy Weaver, a horticultural consultant in New Zealand, said that the fruit industry there is trying to educate people on the other side of the world who buy the apples that the issue should be the total carbon footprint, rather than food miles. He said the report has raised the issue to another level, which should be to the growers' advantage.
Even though the efficiency of tree fruit production in New Zealand compares very favorably already, growers can't be complacent, he said. The goal of all New Zealand tree fruit producers is to become carbon neutral, he said. There will need to be some benchmarks and some accounting method for carbon credits, based not just on direct inputs but indirect inputs and outputs, he said. It might require third-party verification, as is done for EurepGAP certification, for example.
"You've got to go with it," he said. "Some of us see it as a trading advantage, so we're prepared to go over the hurdles and do it. Other guys are going to say, 'It's too hard. I'm not going to do it,' and that shakes it out."
Hugh Dendy, who has cherry orchards in both New Zealand and Canada, thinks retailers see the food miles issue as a marketing device and a way to put pressure on their suppliers. However, he doesn't expect the issue will affect the cherry industry, unless the fruit is airfreighted, because cherries are produced with relatively low inputs, are a luxury product, and are not produced in high volumes. "I think it will affect apples more than cherries," he said.
He noted that the carbon footprint for shipping fruit by sea from New Zealand to the United Kingdom is probably less than for shipping the same fruit from the south of France, and said he'd heard that the way foods are cooked can have a greater carbon impact than transportation. An environmental economics blog claims that not putting a lid on the pan when cooking potatoes can make more of a difference than how they were farmed, or whether they were produced locally or not.
Kyle Mathison, a cherry grower and partner at Stemilt Growers, Inc., Wenatchee, Washington, told the Washington State Fruit Commission board members that Washington producers would like a report to be compiled comparing the carbon footprint of Washington and other growing areas. In Washington, electricity comes from hydropower, and yields are comparatively high, he pointed out.
"Wal-Mart says, 'You're at a 2,000 to 3,000-mile disadvantage compared to eastern apples.' We've got to be somewhat competitive," Mathison said. "We can't eat all these cherries in this state, and if people are going to look at food miles and carbon footprints, we have to have some data that says we're responsible."
David Granatstein, sustainable agriculture specialist at Washington State University, said that in fruit production, there's a positive side to the balance sheet when calculating the carbon footprint. All those 242,000 acres of fruit trees in Washington State are taking carbon from the atmosphere and storing it.
Dr. Alan Lakso, pomologist at Cornell University's New York Agricultural Experiment Station, estimates that an acre of apples absorbs between 10 and 15 tons of carbon dioxide annually, with New York orchards being on the low end, New Zealand orchards on the high end, and Washington in between at around 13 tons per acre. For each molecule of carbon dioxide taken up by the tree, one molecule of oxygen is given off. These estimates are for the trees only, which Lakso estimates capture only about 50 percent of the sunlight. Weed and cover crops would contribute a similar amount.
However, Granatstein said a legitimate calculation of the carbon footprint would need to take into account the entire lifecycle of the tree.
"What happens when you remove an orchard and till it up?" he asked.
If the trees are ripped out and burned, the accumulated carbon goes back into the atmosphere. If, on the other hand, the trees are chipped and the chips burned to produce power instead of burning coal, then there's a carbon offset. Orchards also have a desirable cooling effect. Lakso estimates that during the growing season the cooling effect of an acre of apple trees can be equivalent to about 175 to 200 1,000-BTU air conditioners running continuously day and night. Other plants in the orchard alleyways will add to this effect.