AgBioResearch Quarterly Newsletter - Spring 2012
Spotted wing drosophila response team helps Michigan growers manage the pest
Michigan farmers and researchers are dealing with a new pest that has the potential to create significant economic losses to crops. Spotted wing drosophila (SWD), an exotic vinegar fly of East Asian origin, was first found in southwestern Michigan in late fall 2010. In the western United States, it has already infested numerous fruit crops.
Unlike the native vinegar fly, which is more of an annoyance than a problem, SWD, or Drosophila suzukii, is able to lay eggs in ripe fruit still on the plant, rather than in just overripe or rotting fruit. Populations of SWD can build quickly because multiple generations can occur each year and female flies (which live 20 to 30 days) can lay hundreds of eggs during their life spans. Michigan growers are prepared for this new pest because of the actions of the SWD Response Team, headed by MSU AgBioResearch scientist Rufus Isaacs.
“In the fall of 2009, I attended a workshop in Oregon presented by research and Extension entomologists who talked about the pest, describing how bad it was for them to deal with,” said Isaacs, MSU’s berry crops entomologist. “From their presentations, it was clear that much of the eastern United States was at risk, and although Michigan’s cold winters might limit the pest, our summer climate and its host range looked appropriate enough for us to be concerned.”
Isaacs discussed what he had learned about SWD with fellow MSU fruit entomologists and Extension specialists, highlighting the need for immediate attention. They decided to form the SWD Response Team and involve stakeholders – including the Michigan Department of Agriculture and Rural Development (MDARD), MSU Extension and industry representatives. This group got together to decide how and where to monitor for SWD in 2010.
In other regions, SWD had been reported mostly in berry crops, particularly blueberries, as well as crops of grapes, cherries and other tree fruits, with a preference for softer fleshed fruit. The fruit industry in Michigan is a multi-million dollar business with cash receipts totaling $325 million in 2010, and Michigan is the No. 1 producer of blueberries and tart cherries, so the researchers realized that immediate action was crucial.
Growers, however, were surprised when Isaacs began delivering traps for a previously unknown insect. Twenty-eight counties were monitored for SWD in 2010, and none were found until the third week in September 2010, which was after fruit harvest. SWD continued to be found in traps until late November.
“SWD was found in 13 of the counties monitored by the MSU team in 2010,” Isaacs said. “It was a warm fall season that year, which accounted for the finds so late in the year because SWD activity is predicated on the weather. But there was no economic impact on fruit because all the flies were trapped after harvest.”
Once SWD was found, the SWD Response Team put out the word through the newly created SWD website and informational materials for Michigan growers, as well as presenting SWD information at grower meetings during the winter.
In 2011, the survey was widened, and, as of early December 2011, SWD had been found in nine more Michigan counties. During the year, the team studied trap designs and baits; examined the timing of SWD activity; created an SWD detection survey database; conducted chemical control studies; held SWD workshops for growers, crop scouts, consultants and Extension staff members; presented information at grower meetings; published information in grower publications; and created MSU Extension bulletins and a North Central Integrated Pest Management (NC-IPM) Center pest alert.
Though this pest has great potential to create economic losses, being forewarned means that Michigan fruit growers are more prepared to deal with it.
Shelly Hartmann, president of the Michigan Blueberry Advisory Committee and Michigan Frozen Food Packers Association, said the SWD work is a prime example of how MSU prepares growers for the unexpected.
“The findings shape the future of agriculture,” said Hartmann, who along with her husband, Dennis, own True Blue Farms in Grand Junction, Mich. “It all starts with the farmer on the farm, but it goes far beyond that.”
Isaacs is optimistic about the future in controlling SWD.
“That first year, we were facing a pest that we didn’t know much about,” Isaacs said. “In 2011, growers learned more about it, and they know that it is another pest they will need to add to their integrated pest management program. There are pesticides that can be used to control it in the short term, and we are exploring alternative control tactics. We now have a strategy to manage SWD that will improve as we learn more.”
The downside is that this pest is likely to make fruit farming more expensive for some growers because of the increased costs of production, Isaacs noted. However, efforts to thwart the insect are estimated to have already saved $200,000 in spray applications and $25 million in small berry losses in Michigan.
In 2012, SWD monitoring will employ improved traps that will give growers earlier warning of fly activity so they can better protect their crops. The online reporting system will be used to put out the word on SWD detections quickly to MSU extension educators, crop consultants, scouts and growers. Researchers will continue evaluating various trap designs, searching for biological control options and testing a range of chemical controls.
The SWD Response Team has been “a fantastic example of what can be achieved when people come together to address a problem like this,” Isaacs added. “Researchers from multiple campus labs are linked with the Extension programs in the counties and tree fruit and small fruit growers. Increasing awareness and explaining the solutions have been a really great aspect of this team.”
Isaacs said that Extension educators are monitoring for SWD in their areas around the state. Work on SWD in Michigan has led to collaboration with research colleagues in other eastern U.S. states to develop strategies that can benefit the entire region, he noted.
There is much we can learn from other regions, although we have some specific challenges here that MSU scientists are addressing as part of the response team,” Isaacs said.
For more information on SWD and Michigan’s SWD Response Team, visit http://www.ipm.msu.edu/SWD.htm. MSU AgBioResearch, Project GREEEN, the U.S. Department of Agriculture Specialty Crop Block Grant through MDARD, Michigan grower groups and the U.S. Environmental Protection Agency provide funding for the SWD Response Team and its activities.
Creating a viable market for ecosystem services
What do food crops, clean drinking water and the beauty of vegetated landscapes have in common? All of them are benefits that people derive from nature, what scientists call “ecosystem services.” Despite wide recognition, however, many of these services are not valued through existing markets. Michigan State University (MSU) AgBioResearch economist Scott Swinton is working to measure the economic value of ecosystem services linked to agriculture and identify ways that policy can communicate those values to farmers.
Ecosystem services are divided into four broad categories:
- Provisioning, such as the production of food, fiber, fuel and drinking water.
- Regulating, such as the role of plants and vegetation in maintaining a sustainable climate for human life and the species we depend upon.
- Cultural, such as recreational hunting and fishing.
- Supporting, such as supplying nutrients to plants and crop pollination, which enable the other three types of services.
“The general idea of ecosystem services is that it’s focused on people,” said Swinton, a professor in the MSU Department of Agricultural, Food and Resource Economics. “Where an economist fits into this picture is finding ways to improve the supply of ecosystem services to society.
“Markets work when you have private goods and services that can be bought and sold,” he explained. “You can buy apples or wheat or milk, but you can’t buy cleaner stream water. Many of the regulating and cultural ecosystem services tend to lack markets because they involve things that can’t be privately owned. No one owns the climate or the Kalamazoo River or Lake Huron, and no one owns the whitetail deer population. Yet people care about these things and clearly derive benefits from them. There’s an important role for policy in this arena.”
Much of Swinton’s research involves working closely with biological scientists in the Long-Term Ecological Research Program (LTER) and at the Great Lakes Bioenergy Research Center (GLBRC) -- both housed at MSU’s Kellogg Biological Station in Hickory Corners, Mich. -- on understanding the ecosystem services that come from agricultural systems.
“Historically, we’ve tried to develop technologies that enhance productivity,” Swinton explained. “We continue to do that, but we’re also increasingly trying to develop technologies that improve environmental performance, including some of these ecosystem services that benefit society and have off-farm benefits.
“The big question is, under what conditions would farmers adopt environmentally beneficial, low-input technologies?” he continued. “One part of answering this question is determining what farmers need, and the other part is designing policies that could support those needs.”
To address this challenge, Swinton conducted a study in 2007 to investigate why farmers weren’t adopting some of the environmentally beneficial row crop practices such as cover crop planting, small grain rotation and reduced fertilizer rates.
The research was followed by focus groups and a survey of 3,000 Michigan corn and soybean farmers in 2008. What Swinton found is that farmers are well aware of low-input technologies, but they see implementing these practices as adding to their costs.
“Cover crops require extra labor for planting and seed costs, and they are sometimes hard to kill when it’s time to plant the main crop,” Swinton explained. “Reduced fertilizer levels create the risk that yields might be lower if growing conditions are very good. We did find, however, that large numbers of Michigan growers would adopt these practices if provided an incentive.”
The study findings helped Swinton, fellow AgBioResearch economist Frank Lupi and their team develop supply curves, which show how much land Michigan farmers would be willing to put into these practices for various levels of payment.
Another part of Swinton and Lupi’s research involved asking Michigan residents if they would be willing to pay for the kinds of ecosystem services that these changed farm practices would require. Results revealed that Michigan residents would be willing to pay to reduce the number of eutrophic lakes and the level of greenhouse gas emissions. Those payments could support potentially 20 to 50 percent of Michigan’s corn-soybean land going into low-input practices.
“The hard part is making the link between what farmers do and what non-farmer residents experience,” Swinton said. “The preconditions are there. Farmers are willing to implement some of these practices for certain payments. Residents are actually willing to pay amounts of money that would support significant change. The missing piece is a way to make that connection. Residents see no reason to care whether farmers plant cover crops. But if you can build the connections, you can get to some of the endpoints that they directly experience, such as enjoyment of the lakes where they go swimming or fishing, or their climate change concerns.”
Swinton also points out that farmers are a very diverse group of people.
“They are at different life stages. Some are avid fishers or enthusiastic about environmental stewardship. For these farmers, being environmental stewards is a very important part of their identity. They are more willing to make some of these changes than other farmers who view farming more as primarily an income-generating activity. So there’s a lot of potential there based on individual preferences.”
Although there is still much ground to cover in creating a viable market-based mechanism for agricultural systems, Swinton believes that there is a growing awareness of the need to look at cropland from a broader public benefit perspective rather than simply considering the immediate goods it provides.
“Successfully creating these types of markets for ecosystem services has to make tangible economic sense to all the groups that are affected,” Swinton said. “Being able to demonstrate the full range of ecosystem values and their economic benefits is one part of the equation. Another is to find ways of equitably capturing values and benefits over the long term so that incentives can be put in place to promote sustainable agricultural systems.”
Green roofs growing – in more ways than one – on MSU campus
Take a look at building construction on the Michigan State University (MSU) campus and you may notice a common feature sprouting up: green roofs. Succulent foliage has started to emerge, very slowly taking the place of conventional gravel ballast rooftops.
A new facility built last fall to connect the Plant and Soil Sciences Building with the nearby Plant Biology laboratories sports a state-of-the-art green roof, along with some of the newly renovated dorms in the Brody complex. And this spring, the new Wells Hall addition is slated for an eco-friendly rooftop.
It’s a building enhancement that Michigan State University (MSU) AgBioResearch scientist Brad Rowe hopes to see more of. Rowe has been studying these living roofs on the university’s campus since the first installation at the Plant and Soil Sciences Building in 2004. He explains that the new green roof -- the one installed last fall on the Plant and Soil Sciences Building expansion -- is dramatically different from the one planted there 8 years ago.
“Because of weight restrictions, the first one back in 2004 had a media depth of only 1.5 inches, which limits the vegetation to drought-tolerant succulents such as sedum,” said Rowe, a professor in the MSU Department of Horticulture. “What makes this new green roof different is that its growing medium is mounded up 8 inches in the middle, allowing for a wider plant palette. I planted over 1,200 plugs of 17 native herbaceous perennials and grasses. It is part of a long-term research project to see what species live or die out.”
Rowe studied the original Plant and Soil Sciences green roof for two years after its installation, comparing it with conventional roofing. In general, green roofs better insulate buildings – they keep roof temperatures lower in the summer and higher in the winter. Rowe found that summer rooftop temperatures with a green roof were up to 68 degrees cooler and that heat flux into the building was reduced by up to 167 percent.
Though MSU is now also home to green roof research platforms at the Horticulture Teaching and Research Center, the outdoor classroom at the MSU Children’s Garden and several small research plots (raised beds) on the Communication Arts building, Rowe said that the high costs associated with installation continue to be a major deterrent.
A typical green roof system is composed of 2 to 6 inches of lightweight, engineered soil that drains water, holds roots and nourishes the plants. Sedum is commonly used because of its drought tolerance and its ability to grow in shallow soil without irrigation. Many buildings require substantial structural enhancements to accommodate the extra heft of the soil and plants.
“The main roadblock still remains cost,” he said. “Also, part of the problem in determining the value of a green roof is how to put a value on something like aesthetics, or measuring the community benefit of reduced storm-water runoff in our municipal sewer and storm-water systems, or improved human health due to less particulate matter in the air. Still, the more that are installed, the lower the costs.”
An obvious advantage is reclaiming the vegetative footprint destroyed in the construction of a building, especially in urban areas. Rowe is exploring ways to utilize the rooftop space to grow fruits and vegetables in urban areas where access to fresh produce is limited.
“If there is ample land available at ground level, it probably makes more sense to do it there, assuming the soil is suitable for growing food,” he said. “However, in many urban areas such as New York City, land at ground level is not available. Using rooftops to produce food is utilizing previously wasted space. I think it makes sense for home gardeners or community gardens where the produce is grown and consumed locally, but probably not for commercial production.”
A disadvantage is that vegetables require irrigation and more fertile soils than succulents such as sedum, irrigation can lead to water runoff and pollution problems, Rowe said. These factors need to be quantified to see if they really are a problem.
The benefits of green roofs reach far beyond energy conservation, he added.
“If energy was the only concern, it would be more cost-effective to just add more insulation,” Rowe said. “You’ve got to add up all the benefits such as energy savings; mitigation of the urban heat island; carbon sequestration; storm water management; improved aesthetics; reduction in air, waste and noise pollution; improved human health; increased biodiversity; and increased longevity of roof membranes.”
The MSU program began in 2000 when the university worked with Ford Motor Company to install a 10-acre green roof on an assembly plant in Dearborn, one of the largest in the world.
Green roofs are catching on across the globe. Rowe said the amount of green roof space in North America has been doubling each year since his research began.
“Most of these systems are on government and commercial buildings, but it’s a growing business, and there continues to be a lot of interest.”