Texas A&M Entomology Faculty Visit with South Korean Officials on Future Fire Ant Control

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Young-tae Kim, Director of the Plant Pest Control Division with the Korean Animal and Plant Quarantine Agency (APQA), left, with Dr. Ed Vargo, Professor and Chair in Urban and Structural Entomology. Photo by the APQA

Young-tae Kim, Director of the Plant Pest Control Division with the Korean Animal and Plant Quarantine Agency (APQA), left, with Dr. Ed Vargo, Professor and Chair in Urban and Structural Entomology. Photo by the APQA

Two faculty members from the Department of Entomology at Texas A&M recently traveled to South Korea to help South Korean officials with a recent invasion of fire ants.

The group consisted of Dr. Patricia Pietrantonio, Professor and Texas A&M AgriLife Research Fellow, and Dr. Ed Vargo, Professor and Endowed Chair in Urban and Structural Entomology, who met with officials from South Korea.

The follow-up meeting this year stemmed from a request made in 2018 when researchers from the Korean Animal and Plant Quarantine Agency (APQA) requested help in finding ant experts to collaborate with to help control the invasive ants.

Entomologists from South Korea traveled to College Station in September 2018 to connect with and learn from experts in the areas of insect ecology, systematics, physiology, and genomics, as well as integrated pest management, of fire ants after they were reported in the port city of Busan in the southern part of South Korea.

During the meeting in South Korea in April 2019, Pietrantonio and Vargo discussed with the South Koreans the history of fire ant interceptions the country has faced and the role the Quarantine Service has done in their efforts to intercept them. They also listened to the South Korean’s efforts to test new insecticides and fumigants and for plans to create a genetic database for identifying the source of ants for future interceptions.

Dr. Patricia Pietrantonio speaking to the group about fire ants. Photo by APQA.

Dr. Patricia Pietrantonio speaking to the group about fire ants. Photo by APQA.

The group also toured the site at Incheon Port near Seoul where the first discovery was found. Vargo said the representatives from the APQA were very professional and he was very impressed with their handling of the situation.

“I was impressed with the knowledge and professionalism of the Animal and Plant Quarantine Agency (APQA) personnel in South Korea,” Vargo said. “They (APQA) are responsible for preventing the introduction of unwanted plants, animals, and plant diseases. They have recently intercepted several shipments containing the red imported fire ant. However, given the volume of cargo that come into South Korean ports, it will be a difficult task to find all containers that may have fire ants. They certainly have their work cut out for them.”

Pietrantonio was also impressed with APQA’s decision to seek help in controlling the ants by asking Texas A&M entomologists for their guidance – a invasive ant we have worked on for decades.

Dr. Ed Vargo speaking to the group. Photo by APQA

Dr. Ed Vargo speaking to the group. Photo by APQA

“The administrators and researchers in the Animal and Plant Quarantine were extremely appreciative and welcoming and they were genuinely concerned about the possible survival of the red imported fire ants throughout the winter, especially in the ports and other coastal areas where the soil temperature may have allowed their survival at a certain depth,” she said. “They are further concerned about not knowing currently the country or region of origin of the fire ants they have found, because their preliminary genetic analyses was not conclusive or matched fire ant populations that have been characterized elsewhere.”

The outcome of the meeting resulted in the group signing a memorandum of understanding for future research collaborations if needed.

“If the red imported fire ant continues to be found in South Korea, it is very likely that contacts will be reinitiated, especially to genetically compare Korean fire ant specimens with those across the USA and to determine the physiological changes that may allow fire ants to survive in South Korea,” Pietrantonio said.

Don’t let fire ants ruin your summer, take steps this spring

A ‘dead’ fire ant mound along a fence line in rural East Texas. (Texas A&M AgriLife Extension Service photo by Adam Russell)

by Adam Russell, Texas A&M AgriLife Communications

A ‘dead’ fire ant mound along a fence line in rural East Texas. (Texas A&M AgriLife Extension Service photo by Adam Russell)

A ‘dead’ fire ant mound along a fence line in rural East Texas. (Texas A&M AgriLife Extension Service photo by Adam Russell)

DALLAS – Dealing with fire ants is no picnic, but getting rid of them can be as easy as Step 1, Step 2, according to Texas A&M AgriLife Extension Service experts.

Dr. Allen Knutson, AgriLife Extension entomologist, Dallas, said spring is a good time to control fire ants as this is when they search for food and build mounds, which makes them easier to locate.

Broadcast baits are the core of AgriLife Extension’s recommended treatment. The method becomes effective as temperatures begin to rise and ants begin to gather forage to feed their new brood, he said. But once hot, dry summer conditions set in, fire ants become less active and mounds become less visible as ants go deeper in search of moisture.

“It’s time now in central and southern Texas to put out baits. But we encourage homeowners in north central Texas to wait a few weeks to begin applying baits because of our cooler soil temperatures,” Knutson said. “It’s a good time to apply baits in spring as they are generally slow acting. It typically takes two to four weeks to see results from using baits containing indoxacarb, spinosad or hydramethylnon. Starting as early as possible provides more time to enjoy summer without fire ants.”

Knutson said baits with other active ingredients may require two to six months to achieve results, but often require fewer retreatments. So again, starting early has benefits.

Dr. Mike Merchant, AgriLife Extension urban entomologist, Dallas, noted fire ant activity, especially mound construction, is ramping up following the cool spring weather.

“By all evidence, this should be a typical fire ant year, with fire ants becoming more active over the next month or so,” he said. “Baits are still our best weapon against fire ants, and baiting season in North Texas runs from May to September. This is the time when fire ants will actively pick up baits and bring them to the nest.”

Fire ant mounds are often most visible at this time of year, Merchant said, so now is a good time to treat the biggest and worst mounds with an individual mound treatment, such as a liquid drench, or some form of granular, non-bait, insecticide or dust.

There will inevitably be small colonies that get overlooked by individual mound treatments, so AgriLife Extension still recommends broadcasting baits for fire ant control over the entire yards once the soil temperatures are warm enough for active fire ant foraging, usually around 70 degrees at 1-inch depth, Merchant said.

AgriLife Extension developed the Two Step methods of fire ant control to help consumers make sense of all the products on the market, Merchant said. The Two-Step Program is described in the attached bulletin and can be accessed via Merchants “Insects in the City” website: http://agrilife.org/citybugstest/files/2015/02/L-5070-1.pdf.

“The bulletin targets fire ant control in lawns and the home landscape,” Knutson said. “Where a product can be used, whether a lawn, garden, agricultural production pasture or orchard, is determined by the insecticide label. Users should read the pesticide label to be sure the site they are treating is listed on the product label.”

Products labeled for fire ant control are commonly sold as baits or individual mound treatments, Knutson said. A third category includes a few products that are broadcast over the lawn and kill ants by contact.

The first step in the Two-Step Method is application of a fire ant bait to the treatment area, Knutson said. Baits have the advantage in that users don’t have to find each fire ant colony and treat them directly. They are also are less costly in terms of time and amount of product needed when treating a large area.

“Fire ant colonies can be difficult to find, especially over a large area,” Knutson said.  “With baits, ants pick up the bait and return it to the nest.”

However, baits are slow to work, Knutson said.

For those fire ant colonies in high traffic areas, such as around a mailbox, that must be controlled quickly, follow Step 2 and treat these mounds individually with a contact insecticide.

“Most products applied directly to the mound kill the colony in 1-2 days,” Knutson said.  “If the area has just a few mounds, then it may not be necessary to apply bait. Just go to Step 2.”

Baits do have a limited shelf life, Merchant said. He advises users to discard bait products opened for more than a few months. Users should also make sure products they purchase from stores are not more than two years beyond their production date. If users are not sure of the age of the bait, apply the product around an active fire ant mound. If ants gather the bait and take it underground within a few minutes, it should be fresh and ready to use, he said.

“Many native ant species are beneficial in that they compete for food with fire ants, and some also attack new fire ant queens as they attempt to start a new colony,” Knutson said.  “Insecticides for fire ants also kill native ants, thus only use these insecticides if fire ants are present.”

AgriLife Extension Community Fire Ant Control Program A Template for Success

Elizabeth “Wizzie” Brown (right), entomologist and Texas A&M AgriLife Extension Service integrated pest management specialist in Travis County, demonstrates the proper use of a hand-held spreader for a Wood Glen resident during the recent fire ant education day. (Texas A&M AgriLife Extension Service photo)

by Paul Schattenberg, Texas A&M AgriLife Communications

Fire ant mound

Fire ants and their unsightly mounds are reappearing in many Texas neighborhoods. (Texas A&M AgriLife Extension photo)

ROUND ROCK – For more than a decade, Texas A&M AgriLife Extension Service integrated pest management program specialist Wizzie Brown has been engaged in a community-wide battle against one of the state’s most persistent pests – the fire ant.

Since 2005, Brown and residents of the Wood Glen community in Round Rock, north of Austin, have collaborated in a neighborhood fire ant program to control the proliferation of fire ants, eliminate their unsightly mounds and keep them from biting area residents.

“Fire ants roam from yard to yard and have no regard for property lines,” Brown said. “They’re  easily dispersed during their periodic mating flights, and a high percentage of mounds in Texas have multiple queens, which can live for two to five years and produce up to 800 eggs per day.”

Multiple queens also means there is no territorial behavior, resulting in excessive numbers of fire ant mounds per area, with many actually spread over larger areas than can be seen.

“To my knowledge, the Wood Glen effort in Round Rock has been the longest-running community-wide fire ant program in the state and probably in the U.S.,” Brown said. “We recently carried out the fire ant baiting portion of the program and held our annual fire ant education day for the community.”

The Wood Glen neighborhood has 548 homes and covers over 250 acres. It includes a community park, green belt and walking trails.

“Originally the community came to me,” said Brown, who has been at the AgriLife Extension office in Travis County for the past 15 years. “I got a call from one of the residents who knew our agency was part of the Texas A&M University System and that we provided information and technical assistance on various quality-of-life topics. They wanted to know if we could help them with their fire ant problem, which was pretty extensive.”

Elizabeth “Wizzie” Brown (right), entomologist and Texas A&M AgriLife Extension Service integrated pest management specialist in Travis County, demonstrates the proper use of a hand-held spreader for a Wood Glen resident during the recent fire ant education day. (Texas A&M AgriLife Extension Service photo)

Elizabeth “Wizzie” Brown (right), entomologist and Texas A&M AgriLife Extension Service integrated pest management specialist in Travis County, demonstrates the proper use of a hand-held spreader for a Wood Glen resident during the recent fire ant education day. (Texas A&M AgriLife Extension Service photo)

Brown said she gave a fire ant control demonstration to the residents on the “two-step” treatment method, which is the agency’s preferred fire ant control method. The first step involves semi-annual broadcast applications of fire ant bait. The second step involves follow-up treatments of individual mounds or “nuisance” ant colonies, such as those in sensitive or high-traffic areas.

“The two-step method is less labor-intensive, less toxic and more environmentally friendly than most other means of do-it-yourself fire ant control,” Brown said.

For more details on the two-step treatment method and others, go to the eXtension website at http://bit.ly/2oZoL46 or Texas A&M AgriLife Extension Bookstore at http://bit.ly/2oswCGp.

Brown said similar community-wide fire ant control efforts have also taken place in Bexar and Harris counties in collaboration with the integrated pest management specialists in the AgriLife Extension offices in those two counties.

David Schell, a Wood Glen resident and homeowners association board member, said the treatments in the Round Rock neighborhood have yielded positive results.

“The fire ant program is highly effective at controlling fire ants in both the common areas and homeowners yards,” Schell said. “In the five years I have lived in Wood Glen, I have not seen any fire ant mounds in my yard.”

Brown estimated the overall efficacy of fire ant treatment in the community at more than 99 percent, with “almost zero” sightings of mounds or incidents of children or adults being bitten since treatment began. In addition, a survey Brown conducted on the Wood Glen effort in 2010 documented a 64 percent reduction in pesticide use and $20.73 savings per participating household.

“We only did the front yards with the residents’ permission so they could see what was going on,” Brown said. “They were so pleased with the results they persuaded their homeowners association to put the cost for fire ant control into the budget. Now their homeowner dues pay for two bait treatments per year – one spring and one fall – for the front yards. A few years back, we gave that responsibility over to a pest control company. And each year we also hold a fire ant information day in the community during which we provide information on baits and advice on their proper application for residents who want to treat their backyards.”

Brown said Wood Glen wasn’t the only community in which she and community residents have attempted a long-term fire ant program, but it’s the only one that has lasted.

“We have tried to keep a program going in three of four communities in the Austin area, but they eventually stopped, usually because the community lost the neighborhood ‘champion’ spearheading the effort and the community lost interest,” she said.

Brown said the Wood Glen program’s success has largely been due to active community involvement combined with an engaged homeowners association that has been respectful of residents’ wishes and forthcoming in communications about treatments.

Sam and Leslie Myers, who moved from the Wood Glen neighborhood about four years ago, were involved in fire ant program efforts in the community for about five years.

“There were a lot of stay-at-home moms in the neighborhood and they were tired of their kids getting bit by fire ants both in their yards and the community park area,” said Leslie Myers. “We were the second residents in the neighborhood to take the lead for the program after Wizzie got it started.”

The Myers’ role consisted of coordinating with residents on broadcast baiting timing as well as helping with education day efforts, including providing residents with bait and selling them hand-held spreaders if needed.

“Typically from 100-200 residents came to the community’s fire ant education day,” Sam Myers said.

The Myers also kept the community apprised of their fire ant control efforts through the community newsletter and by giving updates on the program during the annual homeowner association meeting.

“Once the pest control people took over broadcast baiting of the front lawns, they were great to work with and always checked to make sure who had opted out for the treatment,” Leslie Myers said. “And the education day out in the community, where we set up a table and people had to wait in line to get their fire ant bait and spreader, gave residents the opportunity to talk and get to know one another.”

The Myers, who are also Texas Master Gardeners, explained their knowledge of gardening and landscaping was a good tie-in with fire ant control in that it made them aware of beneficial and non-beneficial insects and the need for fewer chemicals in managing their landscape.

In 2011, Brown and her family moved into the Wood Glen neighborhood, where she remains actively involved in the program, providing information and technical assistance, particularly during the neighborhood fire ant education day.

“This is a great family neighborhood and I’m glad I can live here in addition to providing expertise for fire ant control and other aspects of integrated pest management,” she said. “But you don’t need an entomologist living in the neighborhood to have a successful pest management program. All you need is a community champion and people willing to support it.”

Pietrantonio’s Fire Ant Research Featured in Podcast

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Texas A&M Entomology professor Dr. Patricia Pietrantonio’s fire ant research project was recently featured in a video posted by the science media podcast website EarthSky.

The podcast is located at http://earthsky.org/earth/science-fights-to-control-fire-ants, highlights the destructive impact of red imported fire ants (Solenopsis invicta Buren) and the ongoing basic research efforts to conceive better strategies to control this pest.

Pietrantonio’s National Science Foundation-funded project, titled “Neuropeptide Receptors and Identification of Genes in Signaling Networks Involved in Reproduction and Nutrition in the Red Imported Fire Ant”, focuses on localizing the neuropeptide receptors in the brains of both queen and worker ants.

She said the neuropeptide receptors may regulate genes that are involved in ant reproduction (via ovarian development, the egg maturing processes), or sensing the ant’s nutritional status.

Pietrantonio said that knowing the physiological mechanisms by which queens sense their nutritional status, reproduce, and by which task allocation occurs in worker ants would possibly help bring solutions to controlling the ants. According to the United States Department of Agriculture, fire ants have generated up to an estimated $5 billion per year in losses.

To help communicate their research to broad audiences, members of Pietrantonio’s lab collaborated with EarthSky to help produce short educational video podcasts both in English and Spanish for both the web and broadcast. The podcast can be seen on the website at earthsky.org

To see the Spanish version of the video, visit https://youtu.be/J9iQfaqBDLY .

Cooler temperatures often move critters inside

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Writer: Steve Byrns, 325-653-4576, s-byrns@tamu.edu
Elizabeth “Wizzie” Brown, 512-854-9600,  ebrown@ag.tamu.edu

AUSTIN – Hungry hoards of mosquitoes, katydids, crickets, grasshoppers and other assorted pests-Texans have pretty much seen them all this summer, but will the onslaught stop once cooler weather hits?

“The bugs of summer will subside, but a new slate is ready and willing to move right in with you,” said “Wizzie” Brown, Texas A&M AgriLife Extension Service integrated pest management specialist at Austin.

“Usually during drought conditions or when the weather begins to get cooler insects and other arthropods like spiders and scorpions will move indoors. In the case of drought, they are often searching for water, and with cooler temperatures, like us, they want a cozy place to stay.”

Brown is a strong advocate of integrated pest management, a series of practices that when used together manages pests in the  most effective and environmentally sound ways available.

She said simply keeping pests out of the house in the first place is the best and easiest way to keep your family safe. She offered the following tips to accomplish that:

– Prune trees and shrubs so they do not touch or overhang the house.
– Don’t stack firewood or anything else against the house.
– Weather strip doors and windows, especially if you see daylight around them.
– Block weep holes in homes with brick or stone facades using steel wool or copper mesh
where rusting steel wool stains could be unsightly.

– Use caulk or expanding foam to fill cracks and crevices on the outside of the home and around pipe and wire penetrations.

– Keep window screens in good repair.
– Use stainless steel mesh to block attic access points.

“As with any unwanted intruder, the trouble starts once they enter your home,” Brown said.

Brown helped develop AgriLife Extension’s ISEC Home Pest Management Program. ISEC stands for the strategies to best manage  pests. They are; Identify, Sanitize, Exclude and Control.

Check it out at  http://ipm.tamu.edu/isec/ to learn the “Top 10 Most Wanted Pests” and how to control them or join her blog at http://urban-ipm.blogspot.com/  .

Entomologist testing puts bite on many ‘home’ fire ant treatments

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AUSTIN – Resourceful individuals have tried many  different “home” treatments for fire ant control, but unfortunately lots of them simply don’t pass the science test, according to a Texas AgriLife Extension Service entomologist.

Wizzie Brown, integrated pest management specialist for AgriLife Extension in Travis County, has been putting alternative, non-chemical means of fire ant management to the test for the past few years. She now has collected objective, science-based data to either support or reject claims about the efficacy of some of these proposed home treatments.

“I’ve previously tested whether club soda was an effective means of control after getting inquiries from people who had read about this on the Internet,” Brown said. “I also started looking into whether or not other home remedies I’d been told about had any basis in scientific fact as fire ant treatments.”

Brown said her most recent trials dealt with anecdotal information that coffee grounds could be used as a treatment.

“Many gardeners utilize recycled coffee grounds from commercial operations or grounds from their own coffee brewing in their garden for composting,” Brown said. “And since gardeners tend to be rather resourceful, some have tried using coffee grounds for other purposes, including managing red imported fire ant mounds.”

In 2010, Brown tested coffee grounds obtained from the Starbucks “Grounds for Your Garden” program as an individual mound treatment for fire ants. She spread a cup of used grounds over a test mound and noted fire ant activity in and around the mound several times over a 30-day period.

“The home remedy of spreading one cup of used coffee grounds over a fire ant mound failed to kill the fire ants,” she said. “The amount of activity after applying the grounds was the same as on the control mounds receiving no treatment.”

Brown said while coffee grounds make for good composting material, her research showed that when put to the test, they are simply ineffective toward killing fire ants.

“It would be nice to have a handy way to dispose of coffee grounds awhile simultaneously killing fire ants,” she said, “but in this case, it just didn’t pan out.”

Brown also recently tested whether ground cinnamon may be an effective treatment.

“I also received inquiries from Travis County residents and had seen on several Internet sites that ground cinnamon was being touted as a useful fire ant control method,” she said.

Brown established a similar methodology to test the cinnamon, sprinkling one tablespoon over the mound as an individual treatment, noting ant activity several times over a one-month period.

“I applied the ground cinnamon the same way one would apply a pesticide dust labeled for control,” she said.

As with the coffee grounds, Brown compared activity on the treated mound with untreated control-mound activity.

“In this instance, it turned out that there was actually more fire ant activity in the treated mound than the untreated control,” she said.

This spring, Brown will be investigating the efficacy of two other home treatments —  oak ash and cayenne pepper.

“These are two other treatments that have been brought to my attention as possible alternatives to commercial pesticides,” she said. “It should be interesting to find out whether or not science supports their usefulness as a method of fire ant control.”

In 2009, Brown tested club soda as “an environmentally friendly cure for fire ants,” as was stated on a gardening website.

“The site suggested the reader pour two cups of club soda directly onto the center of a fire ant mound to control the colony,” Brown said. “This message found its way into gardening forums and was picked up by media – all without any scientific testing to back it up.”

Brown said the site claimed the carbon dioxide in the soda would displace the oxygen and suffocate the ants, including the queen, killing the entire colony within about 48 hours.

“It also claimed that the club soda would leave no toxic residue, would not contaminate ground water and would not indiscriminately kill other insects or harm pets,” she said. “Pretty much all that part was true, but what wasn’t true was that it would be effective in killing fire ants, unless of course you happen to drown a few in the process.”

Brown said her observations and data obtained from the trial showed there was no evidence of  fire ant  control resulting from pouring club soda onto a mound.

“It did not lead to the ants dying a horrendous death,” she said. “However, it did produce lots of impressive bubbling action.”

Brown said results of the club soda field trial and other home treatments have been or will be posted on the Texas Imported Fire Ant Research and Management Project website at https://fireant.tamu.edu.

She added that the site also shows results of other home remedy field tests by herself and other AgriLife Extension and Texas AgriLife Research ntegrated pest management experts. Other home remedies for fire ant control that have been or will be tested  by agency entomologists include aspartame, molasses, Epsom salts, orange juice and cola.

“There’s a lot of misinformation about home fire ant control out there,” Brown said. “And while it’s important to be environmentally responsible and minimize the use of chemicals that may also kill beneficial insects, harm pets or possibly enter the water table, the thoughtful, careful use of commercial pesticides specifically labeled for control is probably still your best defense against them.”

Brown and other AgriLife Extension integrated pest management specialists in major urban areas of the state also conduct community-wide control efforts. More information on who to contact about these efforts also can be found on the Texas fire ant project website

Fire ants’ ‘aphid-ranching’ skills may be key to their successful U.S. invasion

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January 3, 2012
By: Steve Byrns

COLLEGE STATION – Like Old West cattle barons in a B-western, red imported fire ants are expanding their range and increasing their herds while laying wholesale waste to the range, according to an expert on the issue.

Dr. Micky Eubanks, a Texas AgriLife Research entomologist at College Station, said the ants are using a practice known as “mutualism” to help them thrive despite the estimated $1 billion Americans pour into controlling them annually.

“Mutualisms play key roles in the functioning of ecosystems,” Eubanks said. “In this case, fire ants protect aphids in exchange for the honeydew that aphids produce and the ants eat. Native ants also do this, however a study by our team recently published in the Proceedings of the National Academy of Science determined that mutualisms involving introduced species such as the red imported fire ant can actually enhance invasion success and ultimately disrupt entire native ecosystems.”

Eubanks said the phenomenon has received relatively little attention in scientific circles prior to this study.

The team, consisting of Eubanks and lead researcher, Dr. Shawn Wilder, Texas A&M University entomologist; Dr. David Holway, Division of Biological Sciences, University of California; Dr. Andrew Suarez, departments of entomology and animal biology, University of Illinois and Dr. Edward LeBrun, Brackenridge Field Laboratory, University of Texas, examined how access to food-for-protection mutualisms involving the red imported fire ant aids the success of this prominent invader.

He said intense competition with other ants and insects in the pest’s native Argentina checks their explosive success there, but in the U.S. the invaders dominate the range, running rough-shod over the native ants while making full use of the aphid “cows’” nourishing honeydew.

The research team found that the carbohydrate-rich substance known as “honeydew”- that sticky fecal substance that drips on your car from aphids feeding on tree leaves – is a magic elixir to the ants. It gives them the energetic edge needed to out-forage native species and conquer new territory.

“Laboratory and field experiments demonstrated that honeydew with its high carbohydrate content dramatically increases fire ant colony growth, a crucial factor of competitive performance,” he said. “We examined colony growth by rearing fire ants with and without honeydew-producing aphids. After seven weeks, laboratory ant colonies with access to honeydew-producing aphids were 20 percent larger than those grown with cotton plants, but no aphids, even though both colonies had all the insect prey they could eat.

“Our findings support the hypothesis that although mutualisms help generate and maintain biodiversity in our native flora and fauna, introduced species such as the red imported fire ant can infiltrate these networks and divert resources for their own success with potentially devastating consequences to their native neighbors.”

For more information on the published work titled: “Intercontinental differences in resource use reveal the importance of mutualisms in fire ant invasions,” go to the Discovery Blog article: http://tinyurl.com/7end6gy or for the complete work, go to: http://dx.doi.org/10.1073/pnas.1115263108