Exotic species, pest control and the industry’s next generation

A new exotic invasive threatens legumes

Entomologists and growers are bracing for the biggest invasion of bugs since the brown marmorated stinkbug (BMSB) found its way to soybeans, fruit crops and vegetables.

The bug, Megacopta cribraria, arrived in the Southeast in 2009, but doesn’t yet have an accepted common name as designated by the Entomological Society of America.

“We call it the kudzu bug because we can find it in kudzu or in the vicinity of kudzu 365 days of the year,” said Dr. Phillip Roberts, extension entomologist at the University of Georgia. “It’s a benefit in terms of slowing down kudzu, but the negative is that it’s a pest of soybeans.”

Left, The kudzu bug, Megacopta cribraria, is attracted to legumes such as soybeans and snap beans.


Middle, At a growers’ meeting, Kathy Demchak, senior extension associate at Penn State University, hands out vinegar traps to help growers scout for and identify vinegar flies such as the spotted wing drosophila.


Right, Growers should scout carefully for the spotted wing drosophila, an emerging pest that entomologists predict will have significant potential to damage soft-skinned fruits. Males can be identified by dark wing spots, although this isn’t a reliable definitive identification because other drosophila species have dark wing spots.


Although it might seem like a bonus to have a bug that thrives on an invasive species, Roberts emphasizes that the bug was not purposely introduced to control kudzu. He referenced Dr. Jim Hanula, an entomologist with the USDA Forest Service, who is studying the situation. Hanula said that in one year, the kudzu bug reduced kudzu biomass by 30 percent.

“We’re still learning about the biology of this insect,” said Roberts. “We’ve only been dealing with it for a few years. We know that it overwinters as an adult under tree bark, in leaf litter and other protected areas.”

Roberts says that in Georgia, the kudzu bug has been primarily observed reproducing on kudzu and soybeans. “We’ve seen them on a lot of plant species, but they’re known as a legume pest,” he said. “They also like wisteria and figs, but we don’t know if they’re damaging those plants.”

Once the kudzu bug lands on the soybean plant, it feeds on plant sap, usually on the main plant stem. Roberts refers to the bug as a stress-inducing pest that creates plant stress, similar to what soybeans would suffer in a drought. In trial plots in Georgia and South Carolina, the average yield loss from kudzu bugs in unprotected plots is 18 percent, with a high end of 47 percent – similar to losses observed in China.


As is the case with the BMSB, researchers are still in the early phases of understanding the kudzu bug. “We need to better understand its biology,” said Roberts. “Early work was focused on how to control it with insecticides, and we have a good handle on that. We’ve also established trials to measure yield response. We have insecticides that provide good control, so the next step is research trials to establish optimum times for insecticide applications and how cultural practices influence infestations.”

Roberts says that there’s a research group studying a parasitoid species native to Japan to see if it will be effective against the kudzu bug without attacking native species in the U.S. “After preliminary work, we will apply for a permit,” said Roberts. “It won’t eliminate the kudzu bug, but it will help keep it in check.”

Routine inspection snags invasive

Dr. Jim Young’s job as an entomologist identifier with the Animal and Plant Health Inspection Service’s Plant Protection and Quarantine program (APHIS PPQ) keeps him busy looking for what he hopes he doesn’t find: invasive insects. This past March, Young saw something suspicious during routine inspection of a load of goods arriving from outside the U.S. He correctly identified the potential invader as a red mason bee (Osmia rufa), one of many species of solitary bees.

Solitary bees do not live in large colonies, and for the most part one female collects the food for all of her young. Some solitary bees will have communal nests; however, each has its own chamber with eggs and it only cares for its own young.

Young says that the red mason bee itself is not particularly threatening to our native pollinators, but it is a carrier of several diseases and mites that could severely impact many of our native bees.

Kudzu bugs have been observed to reproduce primarily on kudzu and soybeans. This egg mass is on the underside of a soybean leaf in Georgia.

“With the exception of a few very aggressive social honeybees (Apis sp.) that we would not want for human health and safety reasons,” said Young, “the diseases and pests of exotic bees continue to be the greatest foreign threat to our native bees.”

Invasive targets soft-skinned fruit

Kathy Demchak, senior extension associate at Penn State University, is keeping growers up to date on an invasive insect that was first identified in California and made its way to the Southeast and Northeast in just a few years.

“A few years ago we were worried about whether we’d have the spotted wing drosophila [SWD] here,” said Demchak. “Now it’s here. We had it pretty bad last year, mainly on late-season crops, and there was a quick buildup as the season went on.” Demchak explained that this drosophila, an invasive vinegar fly, was identified in California and other West Coast states in 2008 and in Northeast states in 2011. However, she noted that it’s possible that there were small numbers of the SWD in 2010 and it simply wasn’t identified.

The SWD is primarily a pest of thin-skinned fruit such as cherries, raspberries, strawberries, blueberries, peaches, plums, nectarines, wine grapes and currants. While most drosophila species target overripe fruit, the SWD lays eggs in ripening fruit, resulting in larvae in fruit.

Demchak noted that in 2011, growers who were applying sprays for BMSB didn’t have as many problems with SWD because the spray covered both pests. It’s also likely that weather played a role in whether a particular area had issues with this pest.

“Hurricanes Irene and Lee came one right after the other,” said Demchak. “The SWD was found in Pennsylvania, and within a week they found it in New York, Connecticut, New Hampshire and Maine. It was probably caught up in wind currents and came up the coast. A lot of pick-your-own operations had berries that were so wet that they couldn’t keep up with harvest. This caused a big buildup of SWD populations on some farms.”

Demchak says that the SWD isn’t easy to find and identify, but hopes that new fact sheets and traps will help growers. “The problem with fruit flies is that they’re so little,” said Demchak. “The defining characteristics of the SWD are black spots on the wings of the males. There are two black bands on their front legs, which is the true defining characteristic because there are two other species of fruit fly that have spots on the wings.” Demchak says that growers should be using a magnifying glass for spotting, and using vinegar traps to catch fruit flies and look for SWD.

This red mason bee, identified by entomologist Dr. Jim Young at port of entry in Baltimore, is one of many invasive species entomologist identifiers search for in shipments from other countries.

In addition to the SWD and other emerging exotic species, Demchak believes the globalization of pests will be one of the biggest challenges to the industry. She noted that entomologists are seeing more generations of pests in one growing season, and that it’s difficult to predict short-term outcomes when factors such as weather patterns and introduced pests are considered.

Demchak says a positive trend in the industry is that the number of small fruit growers in Pennsylvania is increasing. “Acreage is going down, but productivity is going up,” she said. “What I’m hearing from growers is that they can sell whatever they can produce, so I think the market is going to continue to be strong.” Demchak added that younger generation growers are looking for ways to diversify operations, and are successfully targeting fresh fruit markets with more unusual fruits such as gooseberries and currants.

Marketing to new generations

While growing for a particular market is important, intricate knowledge of the market is critical. Tom Ford, Penn State University commercial horticulture educator, says that understanding generation differences is the key to effective marketing.

Ford explains that generation X, those born between the early 1960s and the early 1980s, are well-educated, busy and tuned in.

“Generation X likes big-box stores,” said Ford. “It’s much easier for them to pick up a flat of impatiens while they’re shopping for groceries. Getting them to a garden center is a little more of a hard sell.”

Ford says that generation Xers are willing to comparison shop, and because they’re technology-savvy, they’ll do that shopping online. “They’re going to look you up on the Web, and if they can’t find you, they aren’t going to visit your operation,” he said. “About 60 percent of these customers have a higher education, so you have to appeal to their intellectual side. You may have to make a better case as to why they should buy plants from you – what are they going to get out of that transaction? Generation X wants their lives simplified. Think about integrating some kind of contracting such as landscaping, planting or maintenance services.” Ford says that these customers don’t have a wealth of plant knowledge, so it’s beneficial to provide education through tools such as information on websites. He urges growers to study industry trends to determine what customers are looking for.

“In some states, sales of market packs have flattened out or declined,” said Ford. “Four-inch pot sales are either holding steady or declining. However, sales of larger pots including color bowls, hanging baskets, large finished planters and large perennials are increasing, and margins per container are higher.”

Generation Y presents a different challenge. It includes those born between the early 1980s and the early 2000s; the largest group since baby boomers. “This is the group we hope to capture,” said Ford. “This group is more diverse than generation X, and there are significant cultural differences within the group. They’re even more connected with technology than generation X.”

However, Ford says that because those in generation Y have been plugged in and tuned in for so long, they’re often overwhelmed with technology. “Despite all the technology, they desire personal contact and human interaction,” he said. “We’ll have to promote our businesses through technology, but bring them in and show them something hands-on.” Ford mentions a company that isn’t especially technology-oriented yet found success in selling human interaction. “Customers can come in and design their own container, pot their own plants – they’re being entertained and educated at the same time.”

Ford says that generation Y is generally impatient, which means that as consumers they’re looking for instant color and finished landscapes. They think globally and are concerned about issues that impact the world, including the economy. They believe that businesses have a social responsibility to make the world better and help people in need. Generation Y cares about environment and the social record of the companies they deal with.

“While they’re checking you out online they might be checking out your board of directors to see what they’re up to. They’re going to make sure you’re worthy of their dollar,” Ford said.

Impacting and bringing generation Y to the garden center means understanding that generation’s unique outlook. “You have to build [a] positive image in [the] community through social media,” said Ford. “Practice sustainability, use biodegradable containers and recyclables. Let them know about your IPM and other growing practices; it’s important to them. Because this group doesn’t have a knowledge base with plant materials, it helps to choose plants that have stories behind them, something that resonates with the customer such as pollinator-friendly plants, native species, plants that don’t have pest or disease issues or plants they can use in cooking.”

Ford says that many garden centers successfully draw customers with demonstration gardens, especially if they are willing to provide the landscape plan for that garden. “Use common names rather than Latin names,” he said. “If they have a road map to guide them, they’ll buy plants. But we have to make these two generations feel good about gardening. Make it easy for them to be a novice and ask questions. Build rapport with that client. They really just don’t know.”

A Web and social media presence is essential for marketing to both generation X and Y, so Ford suggests that businesses rededicate themselves to educating the customer. “Baby boomers are closer to the farm generations and know more about production. Generation X really never took an interest, and generation Y didn’t get anything from generation X, so we have to go back to square one and figure out how to educate these customers. But the biggest issue is the relationship with the customer.”

The author is a frequent contributor and freelance writer who farms and raises Great Pyrenees in south-central Pennsylvania. Comment or question? Visit www.farmingforumsite.com and join in the discussions.