Change By Degrees: Climate and Kentucky Agriculture

By Carol L. Spence, 
University of Kentucky The mAGazine (Spring 2012)

Don Halcomb doesn't want to be the proverbial frog in a pot.


He looks across his fields and tries to picture what his Logan County farm will look like in the future. He wants to have a good plan in place, but he needs some help to do it.

Halcomb grew up on this land. He remembers a time when he was 5 or 6 years old when his family grew corn to be fed to their cattle and pigs, which were then sold at the stockyards. The only crop they sold off the farm in any great volume was wheat.

"In my lifetime," the 58-year-old farmer said, "the crop rotation has changed unbelievably. We don't have any livestock. All the grains we grow are sold to someone else, and we're growing half our acres in soybeans that we didn't even grow when I was a child. That whole crop rotation has changed in my lifetime, and I think it could change again."

You see, Halcomb is concerned about the effects of climate change.

"The things I've read, it seems to me it's pretty well fact that the global average temperatures are increasing," he said. "I don't really need to hear the argument about why it's happening, as much as the documentation that it is happening, and therefore, I need to learn how to adapt to the change."

Which brings him back to that frog in a pot.

"You know the old story about how to boil a frog? You start him out in cold water, and you let it simmer. He never realizes he's boiled until it's too late," he said. "I think that's where we are with a lot of issues, because the annual change is very small, but I think the impact over time could be large."

Trained to Doubt

George Wagner and Paul Vincelli are skeptics. As scientists in the College of Agriculture, their profession demands that they question and dig deep to find answers. When it comes to the question of whether the earth's climate is changing, they doubt no more. What's convinced them? The scientific evidence and the consensus of nearly 98 percent of the world's most expert climate scientists.

"There are more than 10,000 refereed papers on the subject. I know what it means when climate scientists publish paper after paper after paper in refereed journals about the topic. I know that each one of those is a monumental task to get it through a review process by experts," said Vincelli, who as an extension professor in Plant Pathology has 35 published papers in peer-reviewed research journals to his credit.

George Wagner (left) and Paul Vincelli are skeptics. As scientists, they question and dig deep to find answers.

George Wagner (left) and Paul Vincelli are skeptics. As scientists, they question and dig deep to find answers.

"But it doesn't stop there," said Wagner, who is a professor in Plant and Soil Sciences. "Science never stops questioning the original hypothesis, so it keeps getting polished even after it's published. And that's why it's so significant to me that 97 to 98 percent of expert scientists agree that climate change is real. That's an incredible consensus."

Despite that consensus, the subject of climate change can raise some hackles. College of Agriculture Dean Scott Smith acknowledges the sensitivity of the issue, but also recognizes the importance of additional discussion and research.

"Our role is not to take sides on all the related policy issues, but we owe it to our stakeholders to conduct the research that will keep them competitive in ever-changing world markets, and always variable weather," he said.

To that end, Vincelli pulled together a team of specialists representing all areas of the College to create a Cooperative Extension publication titled "Climate Change—A Brief Summary for Kentucky Extension Agents." The publication and accompanying training sessions for agents are promoting discussion in the Extension Service about climate-related changes that could affect Kentucky and how producers can prepare.

Shattering Records

In a report issued at the end of last year, the National Oceanic and Atmospheric Administrationstated that 2011, with its 12 weather-related billion-dollar disasters, broke the old record set only four years ago, when there were nine such disasters.

Very few will argue that the weather pendulum seems to have swung to the extremes. Speculation on the effects of atmospheric warming by the world's scientists covers everything from rising sea level, to drought, flooding, and wildfires. The Intergovernmental Panel on Climate Change is the leading international scientific body on the subject. In their latest report they stated that multiple stressors such as limited water resources, loss of biodiversity, forest fires, insect outbreaks, and air pollution are reducing resilience in the agricultural sectors. What will all this mean to Kentucky agriculture—the biggest driver of the commonwealth's economy?

Rebecca McCulley and David Van Sanford, both professors in Plant and Soil Sciences, are heading up the College's new Climate Change Working Group. The group includes Wagner and Vincelli and specialists in the diverse fields of animal and plant sciences, entomology, soil, forestry, sociology, economics, and geography, as well as climatologists from Western Kentucky University. Their goals are to identify the most pressing research and outreach issues related to climate change and agricultural production, to set priorities for action, and to generate ideas for enabling Kentucky producers to deal with changing environmental conditions.

Three Degrees of Separation

McCulley, whose area of expertise is forages, has already seen some of the impact of environmental changes through research funded by the U.S. Department of Energy's National Institute for Climate Change Research. At the College's Spindletop Farm, McCulley uses infrared radiant heaters and a plus-precipitation treatment to study the effects an increase in air temperature of three degrees Celsius and/or a 30 percent increase in rainfall will have on forages.

Rebecca McCulley uses infrared heat lamps to raise the ambient air temperature over her forage research plots by three degrees. The result so far? More crabgrass, which might not be a bad thing.

Rebecca McCulley uses infrared heat lamps to raise the ambient air temperature over her forage research plots by three degrees. The result so far? More crabgrass, which might not be a bad thing.

"We saw pretty dramatic changes in the plant community composition faster than I would have guessed we'd see," she said. "We've seen substantial increases in annual C4 (warm season) grasses, which are typically considered weeds here in Kentucky. Crabgrass is a big one."

Four years ago, as she was beginning this project, McCulley would have predicted a reduction in forage yield from hotter temperatures. But now that she's seen these so-called "weeds" turn on under her heat lamps, she's beginning to think pastures will just look different, but the overall quantity of forage production may not go down.

"And we haven't seen major change in the quality of that material either," she said. "My colleagues here in the forage group tell me (crabgrass) is actually a pretty high quality material and cattle will eat it. So far, you never see crabgrass advertised as forage. There is no seed industry for it or breeding focused on it, but I think my research suggests maybe there should be something done on crabgrass in the future. It could fill a useful niche."

Our Own Backyard

The members of the working group believe that atmospheric warming will affect Kentucky agriculture over the next two or three decades. Some of those effects are good, some not so good.

"A 2008 report by Purdue University forecasts wetter springs and drier summers, as climate change progresses," Vincelli said. "So it will be harder maybe to plant, but more importantly, droughts are expected to increase in the region. At a time when you need the water most, we're less likely to get it."

Looking down the road, Halcomb considers the idea that he may have to replace corn with another crop that uses less water in the middle of the summer during extended hot weather.

"We ought to be researching crops that are more tolerant of heat and use water more efficiently," he said.

Katie Russell and David Van Sanford are   examining the impact of climate change on wheat production in Kentucky.

Katie Russell and David Van Sanford are examining the impact of climate change on wheat production in Kentucky.

Halcomb is in a position to encourage that type of work. He is the chair of the Kentucky Small Grain Growers' Association's Promotion Council, and he convinced the association to request proposals for climate change research. The association granted $5,000 to McCulley, Van Sanford, and graduate student Katie Russell for a study examining the impact of climate change on wheat production in Kentucky. Van Sanford, a wheat breeder, explained that the study will include a literature search and assessment of the likely impact of climate change on wheat production and yields in Kentucky. Additionally, the group will host a workshop featuring key climate change scientists. That event will take place February 20 and 21.

"We intend to invite several preeminent scientists in the field, so they can help us decide what the level of our activities should be, given the resources that we have," he said.

Van Sanford is also among more than 50 principal investigators from U.S. universities working on a $25 million Agriculture and Food Research Initiative project, "Breeding Barley and Wheat for Changing Environments." He and his UK team are looking at nitrogen use efficiency in wheat.

"I think we need to be cognizant of climate change and be prepared for variability. This research also dovetails well with the situation in Kentucky and with a lot of the wheat growing regions of the U.S., where farmers have to be very concerned about how they manage their nutrients, not only for their own economic reasons, but for environmental reasons," he said.

Capacity for Change

Looking into a climate crystal ball is iffy at best. No one can definitively say what the climate will be like in the future. But current data does point toward possible scenarios. There is a potential for increased yields for soybeans and reduced corn yields. Cool-season forages might diminish, but warm-season grasses could flourish. Planting times and growing seasons could change, affecting crop selection and rotation. An increased incidence of crop failure and more variability in crop performance from year to year is possible, which would require more emphasis on risk management. Farmers could face increased pressure from diseases, pests, and weeds. And livestock production during the summer months would likely decrease because of the possibility for extreme heat.

The UK Ag team believes the potential is there to adapt to change and even turn things around. Van Sanford has been encouraged by the conversations he's had with growers.

"They can get excited if they think about other crop opportunities or planting date flexibility, things like that," he said. "Farmers are all very forward thinking individuals. Successful farmers pretty much have to be."

"My overall thought is it's time," Halcomb said. "It's certainly time for Kentucky to have the discussion, and we ought to be able to do some research to see how to adapt."