It’s late May, weeks before southern Wisconsin would be locked into a scorching drought, and Kirk Leach BS’78 is worrying about the weather. The grass around his house is already brittle and yellow. A hose snakes across the driveway, trickling moisture over some sad and thirsty new aspens.
But it’s the corn planted just on the other side of his kitchen garden that troubles him. There are patches—hand-high daggers of green—but there is not enough height, not enough uniformity and just plain not enough of it coming up. “This is the last corn I planted, two weeks ago tomorrow,“ he says. “You’d expect a little more growth than that.” He squats above an empty row, probing through three inches of crumbling earth until he unearths a seed, hard and polished as if just spilled from the bag.
Every farmer has an opinion about the weather. Leach remembers when he was young and everything germinated, even seed just thrown on the ground. But in Leach’s mind it’s these little mini droughts—two or three weeks in a row without rain—that have his attention. “Whether that’s significant enough or evidence of climate change I don’t know,” he muses. “Is it because I was a young, carefree 20-year-old like my sons that I didn’t think about it? Whereas now all the responsibility is mine, and so I’m worrying about every time the next rain is going to come?”
That’s the kind of conundrum that climate change presents to Wisconsin farmers as they’re forced to adapt to wild swings in the weather. Some trust the science, but many have questions, too. They’re all practical scientists with their own, very personal sets of data and research concerns.
The reality is that they’re already adapting to climate change, just as they’ve adjusted to so many other challenges. They’re planting earlier. Schedules for vegetable canneries and cranberry harvest have shifted later to reflect consistently warmer autumns. Even the USDA plant hardiness zone map was updated this year, showing Wisconsin a half-zone warmer than in 1990.
But the forecast calls for a whole lot more, in the way of both opportunity and challenges. The simplest take is that slowly warming temperatures may help boost agricultural production by extending the growing season. But higher temperatures could also reduce corn and soy yields and lead to more pest problems. Higher annual rainfall and more intense storms could mean more soil erosion.
Those broad-brush projections are statistical abstractions for any given farmer. Wherever the weather compass spins, the challenge is to craft a livelihood from sunshine, dirt and water.
The silver lining: a generation of stress in the farm economy has left a population of survivors, farmers who are hungry for information and who are lean and agile enough to act on it. If you have the skill and luck to bring a harvest to market, prices have been good. But with input costs soaring ever higher, extreme climate events can make farming seem more like placing a bet than following a business plan.
The growing season in Wisconsin has lengthened by two to three weeks over the last half-century—a big change over a short time. But because spring can be cold and late one year and early the next, some people tend to chalk it up to variability.
Agronomy professor Chris Kucharik BS’92, PhD’97 has no doubt that it’s climate change. Simply put, the earth is like a giant car, and increasing the amount of carbon dioxide is like rolling up the car windows on a sunny day. But under the hood is a series of massive mathematical models that attempt to mimic and forecast such fundamental earth forces as wind, temperature, evaporation and photosynthesis.
Early in his career Kucharik spent a few years in the far northern boreal forests of Canada helping to fine-tune these climate models. When he grew dissatisfied with the abstraction, he decided to try something closer to home: fit agriculture into the models. Honing in on local, Midwestern problems, he became one of the state’s foremost experts on climate and agriculture, with a joint appointment in the CALS agronomy department and the Nelson Institute for Environmental Studies.
Kucharik knows better than most how dense the science can get, but he is adamant that evidence for climate change is clear and overwhelming. In fact, he can even show how it’s helped agricultural productivity in some locations in Wisconsin over the last few decades. It’s not easy to tease out, because crop genetics and management practices have significantly improved over the same period. But trends in precipitation and temperature during the growing season from 1976 to 2006 explain more than a third of the variability in corn and soybean yield trends, he says.
The bad news is that this productivity trend might be hurt by continued warming without adaptive measures. Indeed, for each additional Celsius degree of future warming, corn and soybean yields could potentially decrease. With luck, modest increases in summer precipitation could offset this. Unless, of course, it fails to rain at all.
This general forecast first came in 2007 from the Intergovernmental Panel on Climate Change, the international scientific body that has coordinated the work of thousands of scientists around the world. They projected that without adaptive measures, ag productivity in higher latitudes could decrease by 5 to 20 percent as temperatures climb.
As a co-chair of the ag working group of the Wisconsin Initiative on Climate Change Impacts (WICCI)—a partnership between the University of Wisconsin, the Wisconsin Department of Natural Resources and an array of other agencies and public and private institutions—Kucharik and his collaborators have been checking these projections for Wisconsin. Without adaptive measures, a 2 degree Celsius increase in maximum monthly average temperatures in July and August could reduce yields by 6 percent for corn and 2 to 4 percent for soybeans. A 4 degree increase could lead to corn and soybean yield losses of 22 to 28 percent and 13 to 24 percent, respectively.
That’s a projection over decades, but so much on-farm decision-making is short-term. “If I walk into a room of producers and say that 50 years from now our summer temperature will be on average 3 degrees warmer, so what?” Kucharik asks. “It means nothing. They’re worrying about next year.
“I hear a lot of concern,” he continues. “But I also hear, on the flip side, that people have been farming for three generations and obviously have been adapting to changes in climate with no significant problems thus far.”
Speaking months before the rain stopped and the summer became ruinous for many, Kucharik looks prescient now: “I think the risk is elevated for failure, not only in production but also in economic failure.”
Kirk Leach and his brother Kent farm 1,500 acres scattered south and east of Janesville. Driving around the spread in May, Leach ruminates about his choices this year. For example, the early spring favored weeds; they had to be knocked back before planting. Leach opted to do that by turning the soil with a disc cultivator, at about half the cost of herbicide. He wonders if that cost him precious soil moisture. “Now our fields sit, just waiting on a rain before things start germinating,” he says.
Not everywhere, though—he’s got 500 acres under irrigation. We drive by the newest rigs, covering 65 acres. The total cost of these center-pivot units will be $114,000 and their high capacity wells, another $30,000. That’s a lot of money, but Leach says it will pay for itself in less than 10 years. It’s a hedge against years like this, and it’s also allowed him to diversify into higher-margin specialty crops like mint and peas.
“It’s a hell of a good aquifer,” Leach says of the water beneath the Rock Prairie. But he knows scarcity is relative. What if every field is irrigated and industrial Janesville keeps growing? “Whether there will be an issue someday or not, who knows?”
Sitting in his truck at the edge of a cornfield, Leach grabs a binder filled with Google maps of his fields, each covered with notation.
“Variability,” he says. “You’re playing a guessing game with that every year.” Besides the irrigation, he spends a lot of time tinkering with corn hybrids, and these maps keep track of the 27 varieties he has stretched over 1,000 acres.
“Probably it’s my susceptibility to my salesmen,” he laughs. Decades of his own experimentation have shown that he generally gets better yields on longer-maturity hybrids. And with seed corn now running around $300 a bag, he’s never satisfied with just last year’s winner. “Information is good,” he says, more seriously. “You’ve gotta push the pencil. Every habit you had, you have to constantly question it.”
That’s an attitude guaranteed to make CALS/UW Extension agronomists Joe Lauer and Shawn Conley BS’96 MS’99 PhD’01 smile. Lauer is the state’s leading corn agronomist; Conley specializes in soybeans and small grains. Between them they have 24,000 test plots scattered across the state, maintaining a series of long-running experiments that test planting dates, new hybrids, crop rotations and numerous other management variables.
Lauer acknowledges that this has been a challenging season—as of early August, 20 to 30 percent of the southern tier of cornfields were barren—but he hews carefully to a long view. “Farmers experience weather variability all the time,” he says. Think March was crazy? He has seen farming logs dating from the 1850s that talk about catching grasshoppers in January in the Upper Midwest.
Lauer says a huge part of climate change adaptation is the continuous improvement of genetics being pursued by the public and private sectors. This year alone, 510 varieties of corn are being tested in his trials, including new strains that tout improved drought tolerance. For example, recently developed resistance to the European corn borer helps prevent stalk damage, which allows the plant to better withstand heat extremes. More traits are coming, but it can take seven to 10 years for new varieties to enter production.
Continuing research in crop rotations could improve productivity, decrease inputs and reduce carbon emissions. The research predates his tenure, and he hopes it will continue beyond. “There has to be a public investment into these kinds of projects,” says Lauer, noting that industry could not justify the investment. “Who knows what the questions are going to be?”
Farmers, he notes, have 30 or 40 seasons to get it right. And even simple differences in how each farmer responds to the challenges of the season produce a variability that strengthens the farm economy. “Farmers try a lot of different things,” Lauer says. “Next year if we can plant in March, there will be more people doing it.”
Indeed, Conley planted soybeans on March 29th. Twenty years ago most soybeans weren’t planted until the end of May or the first part of June. Now almost half of soybeans are in the ground by mid-May. That’s partly due to warming trends, but it also reflects better planting equipment, better genetics and new seed treatments.
But research sealed the deal, showing that earlier planting maximizes yield. Plant after May 8th and you start losing about four-tenths of a bushel per acre per day.
That’s the kind of information that growers need to capitalize on. “Growers today are technologically savvy. They are quick to move if they see an opportunity,” says Conley. “The challenge is sorting out which technology pays and enhances productivity and which technology doesn’t.”
Another valuable conclusion: no-till techniques for soybean yield comparably to conventional practices. That’s important because high commodity prices are tempting cultivation on steeper slopes. Meanwhile, extreme rain events are increasingly common. Unless conservation changes are made, soil erosion rates could double by 2050 compared to 1990. “We need to be able to protect our soil,” says Conley.
Indeed, soil health is a critical element of agricultural resilience—the ability to withstand stress. Healthy soils are more productive. They also retain more moisture, generally demand fewer inputs and return more in the way of ecosystem services (waste decomposition, water filtration and other benefits).
It’s no wonder that many of the climate change adaptation recommendations from WICCI’s ag working group feature a heavy dose of soil conservation.
The almost complete laundry list: expand adoption of currently accepted soil conservation practices; review public policy on soil conservation subsidies; improve measurement and monitoring of soil conservation programs and practices; investigate how bioenergy policies and changing production practices influence soil conservation; devise new metrics for the sustainability of soil and water resources; research better accounting of the costs and benefits of soil management choices.
But other forms of adaptation might not even take place in the field. For example, heavy rain poses challenges besides erosion. Many of Wisconsin’s vegetable crops mature underground—potatoes, carrots, onions—and are vulnerable to damage when soil is saturated. High humidity favors disease development, and the overflow of municipal waste systems can flood downstream fields with pathogens.
CALS/UW Extension horticulturist AJ Bussan PhD’97 is investigating potential plant traits to meet these challenges, but he also says that the vegetable industry has created action plans to respond to major rainfall events from a safety and quality perspective. Even simple refinements in storage techniques—particularly temperature and ventilation management—can help overcome damage.
On a sunny day in early June, Ed Grygleski’s cranberries are in bloom and the bees are busy. Two semi loads of hives arrived the previous week and already are settled in. Some of his fellow growers weren’t so lucky, and their bees are still in transit from other states.
Grygleski has never gotten bees in May before, but he’s also never seen a cranberry blossom on May 15th. “If I didn’t have all my bees right now I’d be screaming on the phone,” he says. “This is perfect weather for pollination.” The more blossoms the bees visit, the better the harvest.
Grygleski’s relaxed demeanor belies a crazy year. The mild March awoke his plants, but then it got cold again and stayed cold. He struggled for more than a month to protect the early vines—not always successfully.
“You can tell the color’s different, the vines just look sick,” he says, pulling up to a damaged bed. “The buds don’t grow out.” The bed will recover, but he estimates an 80 to 90 percent loss this year.
CALS/UW Extension horticulture professor Rebecca Harbut is still trying to assess the overall damage. She believes that three climate-related events combined to stress the bogs. Last fall was warm and dry, then it snapped cold in December. A mild winter made it difficult to establish the ice that growers use to protect their beds. Finally, March temperatures soared to the 80s, followed by a cold and very dry April. Some growers protected with sprinklers, but very dry air lowered the dew point, making frost more likely. The remaining growers flooded their beds but had to keep them submerged as long as three weeks.
There’s more bud damage than usual, and bizarre growth patterns have ensued. “We do not understand what happened,” Harbut says. “Clearly the physiology of the plant got confused.”
The irony here is that cranberry growers are perhaps better prepared for frost events than anyone, and still they got burned. Now Grygleski has a new automated pump system with 13 wireless probes for bed temperature and soil moisture positioned around the farm. The system will save a lot on energy and water as well as improve response time to frost danger.
“Every fruit crop I work with has been absolutely hammered this year,” notes Harbut. One example: the false spring lured Door County cherries into an early bloom, and few blossoms survived the reversal. An estimated 90 to 95 percent of the crop was lost.
Spurred by the challenge, Harbut is now spearheading a research proposal by cranberry researchers across the country who want to figure out how to best adapt to climate change. Industry support is strong. “There has always been a lot of risk in farming,” she says. “The last 10 years it’s gone up exponentially because of the unpredictability of the weather.”
Meanwhile, in London last March —during that unseasonably warm spell in Wisconsin—the independent Commission on Sustainable Agriculture and Climate Change released a report on how to “sustainably intensify agricultural production while reducing greenhouse gas emissions and other negative environmental impacts.” Among its select contributors was just one American, CALS genetics and agronomy professor and former dean, Molly Jahn.
While we’re conditioned to look for major technological breakthroughs, Jahn and her colleagues believe the key to climate change adaptation is information: more of it, integrated better and shared freely. “If we’re going to better manage our agriculture for this twin purpose of our species’ survival and planetary care, we need to have much better ways to keep track of what we’re doing in real time and in multiple dimensions,” Jahn told a Madison radio host in an interview from London. This means everything from space-based sensors to help predict pest expansion to economic intelligence to help ease spikes in food prices and shortages.
Locally, information also is the centerpiece of WICCI’s recommendations for Wisconsin: learn more, and share it with the ag community. One tool the state currently lacks is the kind of detailed local climate monitoring found in such neighboring states as Iowa, Illinois and Michigan.
“We need to arm ourselves with enough information to help adapt to a future state of the climate and resource availability,” says Kucharik.
The politically sensitive nature of climate change doesn’t help. “Part of the ag community feels they are being blamed for climate change,” Kucharik explains. He particularly understands the concern that there may be more environmental regulation.
Unfortunately, he says, the distrust runs so deep that sometimes producers won’t talk to grad students who are trying to understand management decisions. That’s a big problem—but one potentially answered with a historic ideal. “I think this all depends on executing the Wisconsin Idea to its fullest,” says Kucharik.
“Good, bad or indifferent, politics are part of science today,” says Shawn Conley. The challenge, he says, is to be able to talk about it. “Because when it comes down to feeding the 9 billion or so people we’re expected to have on the planet in 30 years, I think U.S. growers are going to be vital in doing that. We have to be. And to do that we have to have frank discussions based on science.
“We don’t always agree, and that’s fine. But we also have to understand that, with the costs now in equipment, inputs and land, the risk has never been greater for a grower to make a lot of money—or to lose the farm.”
SIDEBAR — Plague of Pests
If you enjoyed the early earthy morel or the delicate blooming of lilacs ahead of schedule, know this—the dreaded seed corn maggot cometh too. These three harbingers of spring are typically in sync, and remained so this year, all of them three weeks early.
Wisconsin winters offer a huge pest management advantage over more southern climes, where farmers have to manage aggressively for resident insect pests year-round. A little extra heat and a little extra time is a compounding problem. For the onion thrips it can be the difference between a single female breeding 30,000 replacements—or 15 million.
CALS/UW Extension entomologist Russ Groves says the balmy March drew a lot of insects out of hibernation, including the dreaded
Colorado potato beetle—also three weeks early.
Meanwhile, non-resident pests arrived ahead of schedule. Farmers have been taught to start looking for the potato leafhopper by the first of June. This year, it arrived by May 10. “Growers are going to have to reset their clocks,” says Groves.
The squash vine borer and squash bugs are just two pests that have established full-time Wisconsin residency in the last 20 years, says Groves. “If that happens with the seed corn maggot, that could really change the pest landscape.”This article was posted in Agriculture, Environment, Fall 2012, Features and tagged Agronomy, CALS Extension, climate change, colorado potato beetle, drought, Entomology, Erik Ness, Farming, Kirk Leach, onion thrips, Pests, plague, plague of pests, Russ Groves, seed corn maggot, sidebar.