Cranberries are headed north
Farmers see signs that the climate-sensitive cold-loving berries are shifting their range into Canada. Blueberries, too. What's to be done?
When Rod Serres thinks about cranberries, he doesn't see them beside a Thanksgiving turkey. Another bird comes to mind: a canary in a coal mine. That's because, like all berries, cranberries are very sensitive to climate, making them the agricultural harbinger of global warming in America's Northeast.Skip to next paragraph
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"The cranberry is pretty highly adapted to its specific environment, its niche in life," says Mr. Serres, principal scientist for Ocean Spray, an agricultural cooperative and juice company headquartered in Lakeville-Middleboro, Mass. "And if you change its environment, it's probably going to be affected more than most species"
Cranberries were a late-season staple for native Americans in New England for thousands of years and have played key roles in American history, historians say. Early European settlers in Plymouth survived cold winters with help from cranberries, which native tribes taught them to harvest from the region's bogs.
Now the red berry, ubiquitous during the holiday season, is expected to retreat north later this century, deserting some key growing regions.
A recent report by the Northeast Climate Impacts Assessment (NECIA), which looked at the impact of global warming on the Northeast's character and economy, says the region's food commodities are likely to be hit hard, with berries perhaps feeling it most of all. The report, a two-year collaboration between the Union of Concerned Scientists (UCS) and a team of more than 50 independent scientists and economists, points to two greenhouse-gas-emission scenarios (one high, one low) mapped out by the Intergovernmental Panel on Climate Change. The NECIA used the data to forecast a range of climate effects in nine states, from New Jersey to Maine.
A host of environmental pressures are exacerbated by global warming, scientists say, ranging from more weeds and pests to reduced winter chill periods. That could threaten the viability of berry production generally, while all but wiping out cranberry and Concord grape production in the region's southernmost states. The report warns that as temperatures rise and growing seasons lengthen, the minimum chilling requirement needed for fruiting buds to mature may not be met, causing a precipitous drop in fruit yield as far north as Massachusetts.
Peter Beaton, a third-generation cranberry grower here in Wareham, Mass., near the Cape Cod Canal, has seen growing effects from what he concludes is a warming climate since the 1970s.
"Quite often, when you would get into late October or the first of November, there would be an inch or two of ice on the bogs when it was time to harvest the cranberries. And that was not a rare occurrence – that was a common occurrence," says Mr. Beaton, outgoing president of the Cape Cod Cranberry Growers Association (CCCGA). He can't recall a time once during the past 10 years when the cranberry harvest was delayed because of ice. The CCCGA, founded in 1888, represents 87 percent of the cranberry growers in Massachusetts.
Cranberry growers can flood bogs to shield their crop from winter frosts and summer heat, thereby protecting the cranberries from temperature extremes. Other berry growers cannot resort to such tactics, as most berries cannot survive submerged for very long.
A sharp frost in late April 2007 ravaged grape and blueberry blossoms that had emerged during an unusually warm period, killing up to 90 percent of the blossoms from Missouri to Alabama and the Carolinas. This type of stop-and-go winter is exactly what people in New England's lucrative berry industry are concerned will become more frequent.
Some researchers are less concerned about temperatures being cold enough to mature fruit than they are with erratic weather patterns brought on by climate change. More frequent droughts and floods, as well as salt-water incursion from hurricanes and rising sea levels pose serious risks.