WSSA Scientists Stress the Importance of Early Response to Invasive Weeds

Posted on March 26, 2013

 

Over the past decade, dozens of “early detection, rapid response” initiatives have been launched by states to keep invasive species from devastating natural habitats and damaging our economy. Many of these programs use mobile apps and online databases to revolutionize how we collect data on harmful invaders – making it easier to map infestations and to share information broadly.

But scientists with the Weed Science Society of America (WSSA) say one part of the equation is missing: We often fail to take prompt, effective action based on what we learn, despite the advantages of early intervention. Studies show that small, newly established invasive weed populations can expand at rates of up to 60 percent per year. As the size of the infestation increases, the cost of control soars while the probability of successful management plummets.

“Early detection creates opportunities for us to make smart decisions and eradicate new invasive weeds before they spread widely and become entrenched,” says John Jachetta, Ph.D., chair of the Indiana Invasive Species Council and a member of the WSSA Science Policy Committee. “In those early stages, control efforts are typically easier, more successful and far more cost effective.”

Unfortunately there are many examples of a known infestation unfolding without early intervention. One of those involves common crupina (Crupina vulgaris), a noxious weed in the sunflower family that can ruin valuable pastures and prairies.

A native of Europe, common crupina was first discovered in the U.S. in Idaho in 1969. But there were no concerted efforts to destroy that small initial infestation. A decade later, the weed covered many thousands of acres and had earned a Federal Noxious Weed designation. Only then did research get underway to explore the possibility of eradicating the plant.

It took years, though, to complete a study, and years more to convene a task force to review the study results. By then common crupina had spread well beyond Idaho into other neighboring states – making true eradication a very costly, time consuming and unlikely proposition.

There are also examples, though, of a more effective approach. Some states and municipalities have launched action-oriented “early detection, rapid response” programs that are producing impressive results.
In California, early detection and early response prevented a potential environmental disaster triggered by “killer algae” (Caulerpa taxifolia). A native of Europe, killer algae is a prolific producer of a chemical that is toxic to fish and other organisms. It also is easily spread since small pieces of the plant can break free and grow into new colonies. Once the algae is well established, eradication is almost impossible.

In 2000, a small infestation of killer algae was discovered in a lagoon in San Diego County. Soon after, a second infestation was discovered in a nearby harbor in Orange County. Knowing the potential damage killer algae represented to fishing and recreation, multiple agencies at the local, state and federal level sprang into action and coordinated a response.

Black plastic tarps and chlorine were used to kill the algae at both sites. In addition, recreational divers were trained to spot the weed and to sound an early alarm if there were new outbreaks. As a result, what could have become a very costly problem appears to have been quickly and successfully resolved.

“We’ve long understood the value of an early response to diseases impacting human health,” Jachetta said. “It’s time to bring that same sense of urgency to our natural environment and to take prompt, effective action to stop harmful invasive weeds.”

Early Detection, Ready Response: Seven Critical Steps

An effective program for “early detection, rapid response” will incorporate these seven important steps.

1. Identify. Both scientists and lay people are taught to identify problem plants.
2. Report. Online tools make it easy to submit information on a sighting.
3. Verify. Scientists validate reports of suspected invasive species.
4. Review. Data is used to keep tabs on the geography of an infestation – where the invasive weed has been spotted and how quickly it is spreading.
5. Assess. Experts evaluate the risk of the infestation to natural ecosystems, crops and the economy.
6. Establish a plan. An integrated plan is developed for managing the infestation.
7. Rapidly respond. The plan is quickly implemented and there is ongoing monitoring to gauge the effectiveness of control efforts.

WSSA stresses early response to invasive weeds

Weed Science Society of America  |   March 27, 2013 

Over the past decade, dozens of “early detection, rapid response” initiatives have been launched by states to keep invasive species from devastating natural habitats and damaging our economy. Many of these programs use mobile apps and online databases to revolutionize how we collect data on harmful invaders – making it easier to map infestations and to share information broadly. 

But scientists with the Weed Science Society of America (WSSA) say one part of the equation is missing: We often fail to take prompt, effective action based on what we learn, despite the advantages of early intervention. Studies show that small, newly established invasive weed populations can expand at rates of up to 60 percent per year. As the size of the infestation increases, the cost of control soars while the probability of successful management plummets.

“Early detection creates opportunities for us to make smart decisions and eradicate new invasive weeds before they spread widely and become entrenched,” says John Jachetta, Ph.D., chair of the Indiana Invasive Species Council and a member of the WSSA Science Policy Committee.  “In those early stages, control efforts are typically easier, more successful and far more cost effective.”  

Unfortunately there are many examples of a known infestation unfolding without early intervention. One of those involves common crupina (Crupina vulgaris), a noxious weed in the sunflower family that can ruin valuable pastures and prairies. 

A native of Europe, common crupina was first discovered in the U.S. in Idaho in 1969. But there were no concerted efforts to destroy that small initial infestation. A decade later, the weed covered many thousands of acres and had earned a Federal Noxious Weed designation. Only then did research get underway to explore the possibility of eradicating the plant. 

It took years, though, to complete a study, and years more to convene a task force to review the study results. By then common crupina had spread well beyond Idaho into other neighboring states – making true eradication a very costly, time consuming and unlikely proposition. 

There are also examples, though, of a more effective approach. Some states and nicipalities have launched action-oriented “early detection, rapid response” programs that are producing impressive results......more

Friday's Invasive Weed Resource

It's National Invasive Weeds Awareness Week

Looking for Invasive Species Lists?
Check out the National Invasive Species Information Center

Wednesday's Invasive Weed Resource

It's National Invasive Weeds Awareness Week

Looking for resources on invasive weeds?
Check out the Center for Invasive Plant Management

Tuesday's Invasive Weed Resource

It's National Invasive Weeds Awareness Week

WeedUS -- A database of plants invading natural areas in the United States

National Invasive Weeds Awareness Week

It's National Invasive Weeds Awareness Week

Check out Garden Smart and learn what plants in your garden could be the most invasive!

Scientists research foreign bugs to help kill invasive plants in Midwest

By John Keilman, Chicago Tribune reporter


Across the Midwest, scientists are fighting an invasion of exotic, fast-spreading plants with imported insects that have one simple mission:

Eat and destroy.

It's an old agricultural tactic known as biological control, used here in recent years to dramatically cut down the scourge of purple loosestrife. Researchers are now looking into new bugs to sic on other plants in the rogues' gallery of Illinois vegetation: garlic mustard and buckthorn.

The insects travel and sustain themselves, so they can be a herbicide-free way to stop marauding plants on public and private property alike. For area homeowners it could mean getting control of their yards without putting down gallons of spray.

But the strategy is not without risk. Some alien insects are only moderately effective while others have become nuisances, chewing up flora they were not supposed to eat and spreading far beyond their intended boundaries.

It leaves even some practitioners of biological control uneasy about the potential consequences of unleashing new waves of miniature mercenaries.

"There's always that apprehension: Things are great now, but what will things be like [in the future]?" said Dan Thompson, an ecologist with the DuPage County Forest Preserve District. "Will something we bring in now haunt us down the road?"

Biological control uses an outsider to beat an outsider. When purple loosestrife, a flowering weed native to Europe, began taking over fields and forests in Illinois, officials turned to an insect that loved snacking on the plant back in the old countries.

Galerucella calmariensis, a tiny brown beetle, was released across the Chicago area in the mid-1990s. Its success was dramatic. The purple tide receded where it had crowded out native species, and plants such as wild iris, Joe Pye weed, blue joint grass and turtlehead began to return.

"There were literally thousands and thousands of acres of loosestrife up here 10 years ago," said Ken Klick, a restoration ecologist with the Lake County Forest Preserve. "And though it's still around, you don't see the monocultures you used to. We're very pleased."

The loosestrife campaign led to plans to take on other Midwestern plagues. The next target on the hit list is garlic mustard.

Imported from Western Europe as a delicacy in the 1860s, the piquant herb gradually spread out of control, covering forest floors like a carpet and smothering already established plants.

Within a year, researchers in Minnesota and New York hope to unleash a German weevil that devours garlic mustard from root to leaf. They've been looking at the bug for a decade, plying it with dozens of other plants to learn whether it might eat anything else.

"We want to make sure the only plant that will be attacked is garlic mustard," said Bernd Blossey, who is doing research at Cornell University.

Scientists have also looked for insects to combat teasel, an up-and-coming nuisance that has blanketed Illinois during the last 20 years. They have found contenders among European fleas and butterflies.

But the king of all plant invaders—buckthorn, an aggressively spreading shrub that starves native species of sunlight—might be the most resistant to an insect assault.

David Ragsdale, a professor of entomology at University of Minnesota who is researching buckthorn's insect enemies, said 50 species tested in Europe were rejected because they eat other vegetation. Meanwhile, the five he brought to his quarantine lab for further study—an aphidlike bug called a psyllid and various caterpillars—aren't voracious enough.

"The insects we've found so far are not exciting from my standpoint," he said. "They don't do a tremendous amount of damage [to buckthorn]."

He's still searching for other candidates, including insects that attack buckthorn found in Asia.

So far, the bugs that have been released in Illinois have been problem-free, but that's not always the case. The most notorious local example of biological control gone haywire is the multicolored Asian lady beetle, a bug brought to the U.S. as early as 1916 and used to control aphids on Southern pecan trees.

With no natural predators in this country—birds don't care for the foul-smelling goo within the beetles—they multiplied quickly, becoming an inescapable annoyance in Illinois and elsewhere.

More serious is the case of an Argentine moth that dines on prickly pear cactus. Australians imported the creature in the 1920s to curb the spread of the cactus, which had been planted as a living fence. The moth worked splendidly, said George Schneider, biological administrator with the Florida Department of Agriculture.

Then other countries started using the moth, and in 1989 it appeared unbidden in the Sunshine State, chewing its way through already rare cactus species. It has since spread west, and agricultural officials fear eco-disaster should it make it to cactus-rich regions in Texas and Mexico.

Researchers are trying to curb its spread by releasing irradiated moths that will mate with the cactus killers to produce sterile offspring, Schneider said.

Experts say biological control will expand as global trade, intentionally or otherwise, brings more invasive plants to the U.S. Some say the risks should be measured against the environmental damage of herbicides and the certain toll of inaction.

"Are you willing to go out every year and cut and cut and spray and spray just to hold the line, or can you look for some solution that lasts for a long time?" said Dave Voegtlin of the Illinois Natural History Survey, which helped to introduce the loosestrife-eating beetle.

"Exotics continue to come in. Our water and soil are just full of them. They're changing the dynamics of our system."

Weed Science Society of America Invasive Plant Spotlight: Algae-Harboring Hydrilla Causing Bald Eagle Deaths in the Southeast

WSSA Press Release

The Weed Science Society of America brings awareness to the issues surrounding invasive plants. The aquatic invasive plant hydrilla (Hydrilla verticillata) harbors a blue-green algae which is potentially toxic to birds. Birds--namely waterfowl--eat the algae-harboring hydrilla, become poisoned and eventually die from a disease known as avian vacuolar myelinopathy. Eagles that prey on infected waterfowl contract the disease and perish as well. Hydrilla is most prevalent in the southeast but can be found in fresh water lakes and rivers in most coastal states

Lawrence, Kan. (PRWEB) April 1, 2008 -- The aquatic invasive plant hydrilla (Hydrilla verticillata) not only is a costly nuisance impeding waterways and recreational lakes, it also may have deadly impacts on eagles and waterfowl. Its invasive nature earned it a spot on the Federal Noxious Weed list in 1979 and it is the topic of this Invasive Plant Spotlight from the Weed Science Society of America.

Hydrilla is a quick growing, invasive plant that forms a dense mat in lakes, ponds and reservoirs. It is a safe haven for the fast-growing epiphytic cyanobacterial algae, a blue-green algae, which grows on top of the hydrilla and is potentially toxic to birds. It is suspected that when waterfowl, namely coots, eat the algae-harboring hydrilla, they become poisoned by the algae's neurotoxins and subsequently suffer from a neurological disease known as avian vacuolar myelinopathy. The eagles, in turn, eat the infected coots and succumb to the disease as well.

"According to the research, avian vacuolar myelinopathy was first documented in 1994 at DeGray Lake in Arkansas," says Susan B. Wilde, Ph.D., research professor at the University of South Carolina and member of the Weed Science Society of America. "Since then, more than one hundred bald eagle deaths are believed to be associated with the disease. And it is estimated that the numbers of deaths are much higher, but because of scavenging animals, it often is difficult to recover the carcasses of dead eagles soon enough to test for the disease. But in places where dead eagles are found, invasive aquatic vegetation---primarily hydrilla---and the blue-green algae are always present," says Wilde.

Hydrilla is an invasive plant that originated in India and Asia. It was first introduced into the United States as an aquarium plant back in the 1950s. Improper disposal of hydrilla from aquariums, distribution through animal contact and the plant's ability to "hitchhike" on boats that have been in multiple bodies of water and not cleaned underneath after each use, has lead to its voracious spread over the years. "Hydrilla is most prevalent in the southeast but can be found in fresh water lakes and rivers in most coastal states," says Wilde.

Hydrilla is just one example of a problematic invasive plant. The overall effects of invasive plants on the nation's agriculture, water quality, wildlife and recreation have been estimated to cost the U.S. $34.7 billion annually, according to a recent Cornell University report.

The Weed Science Society of America educates the public on the issues surrounding invasive plants. The information and awareness the Society provides about the destructive effects of invasive plants, assists researchers, scientists, land management professionals and the general public in limiting their spread.

For more information about invasive plants, contact Lee VanWychen, Director of Science Policy for the Weed Science Society of America, at 202-746-4686 or visit www.wssa.net.

About the Weed Science Society of America: The Weed Science Society of America, a non-profit professional society, was founded in 1956 to encourage and promote the development of knowledge concerning weeds and their impact on the environment. The Weed Science Society of America, promotes research, education and extension outreach activities related to weeds; provides science-based information to the public and policy makers; and fosters awareness of weeds and their impacts on managed and natural ecosystems.

Web Resource: Midwest Invasive Plant Network

I thought sharing some of my favorite resources would be beneficial to some people. You'll want to bookmark this one!

One reference I check frequently and has some great information is the Midwest Invasive Plant Network.

Thursday's Invasive Threat to Illinois: Giant Hogweed

Giant hogweed introduced into North America in the 1900’s. Previous to the positive identification in Illinois, this weed has been found in 14 other states including Connecticut, Indiana, Maine, Maryland, Massachusetts, Michigan, New Hampshire, New Jersey, New York, Oregon, Pennsylvania, Vermont, Washington, and Wisconsin. It is listed as a federal noxious weed and is illegal to bring into the United States or bring across state lines. It has been planted as an ornamental in the United States and may have also been brought into the counry for its fruit which is used as a spice (golmar) in Iranian cooking.

Identification
Giant hogweed is a biennial or perennial herbaceous plant which grows to a height between 8 and 15 feet tall. It can have a taproot or fibrous root system. Its stems are hollow, between 2 and 4 inches in diameter, with dark reddish-purple splotches and coarse white hairs. Leaves are compound, lobed, deeply incised and may grow up to 5 feet in width. Flowers appear in mid-May through July. Characteristic of the carrot family, the flower heads are umbrella-shaped, up to 2 ½ feet in diameter across a flat top with numerous small flowers. The plant produces flattened, oval shapes seeds about ⅜ inch long and tan with brown lines.

Giant hogweed is commonly confused with several other plants. Cow parsnip, poison hemlock, and angelica are commonly mistaken for giant hogweed. The two sites listed below offer descriptions and comparisons between giant hogweed and look-a-like plants.

Hogweed Look-Alikes
Giant Hogweed and Similar Species


Environmental and Public Health Hazards
Due to its highly competitive and aggressive nature, giant hogweed is likely to naturalize in many areas where it was first introduced. Plants do well in many habitats can quickly dominate an area.

This plant poses not only an environmental, but also a public health hazard. Its clear, watery sap is capable of causing photodermatitis. The plant sap produces painful, burning blisters or even painless red blotches that may turn purple over time and persist for a year or more. For an adverse reaction to occur, the skin must come in contact with the sap, must be moist (perspiration), and then exposed to sunlight.



Control
Mowing, cutting, or weed whacking are not recommended control strategies due to the plants large perennial roots system and its ability to set new growth. These measures also increase the chance of homeowners coming in contact with the plant’s sap.

Digging up the plants is one of the most effective non-chemical methods of control of giant hogweed. Protective clothing should be worn when working near this plant, including protective eye gear, rubber clothes, long sleeves, and pants. Multiple efforts may be required to completely control hogweed with this method. Cut the plants below the ground and try to remove tap roots to prevent regrowth. Continue to monitor the area for emerging plants.

Applying glyphosate is an option for chemical control. This is a systemic herbicide that is absorbed by the leaves and will move into the root system to prevent regrowth the following year. This is a broadspectrum herbicide, be careful to avoid spraying any desirable plants. The optimum time for application is during the summer months when the plant is green and actively growing. The herbicide will take time to work, so it may take up to a week for symptoms to appear. Repeated applications may be necessary. There are several home-use glyphosate products available. Please follow all label instructions.

For more information and photos

Invasive Species.Org Fact Sheet
Species Profile from InvasiveSpeciesInfo.Gov
Giant Hogweed in Connecticut
Giant Hogweed in Massachusetts

Photos are property of www.invasive.org

River to River Cooperative Weed Management Area

FOR IMMEDIATE RELEASE
July 12, 2007

IDNR Joins Partnership to Address Growing Invasive Species Issues

World trade and travel moves plants around the globe, resulting in the unwanted spread of non-native, potentially harmful plants across the United States including Southern Illinois.

SPRINGFIELD, IL - The Illinois Department of Natural Resources is joining a unique local partnership of 13 state and federal agencies, The Nature Conservancy and Southern Illinois University, called the River to River Cooperative Weed Management Area (CWMA), are working together to coordinate efforts against invasive species in Southern Illinois.

The CWMA’s mission is to establish a framework for cooperatively addressing the short and long term effects of non-native invasive plants across jurisdictional boundaries within eleven counties: Alexander, Gallatin, Hardin, Jackson, Johnson, Massac, Pope, Pulaski, Saline, Williamson and Union.

Numerous non-native invasive species have been identified in Southern Illinois. Plants, like bush honeysuckle, invade woodlands and forests. As a result, they can displace native species, reduce the habitat for native wildlife to thrive, and even prevent tree seedlings from establishing, potentially harming future generations of Southern Illinois oak and hickory forests.

Other species can invade aquatic habitats. The curly-leaved pondweed, for example, is invading lakes and streams, choking out native species and making it difficult for anglers to fish through the thick mats of vegetation. Exotic invasive species are reported to cause over $137 billion of environmental damages and economic losses every year in the United States.

“Most people aren’t aware of the impacts invasive plants are inflicting on our wildlife habitat, fisheries, and native plants,” said IDNR Acting Director Sam Flood. “These plants are choking out and out-competing with our native species. This is a serious problem and probably the greatest conservation challenge of our time.”

The Cooperative Weed Management Area was formed to try to stop this tide of invaders.

“Previously, managers were limited to controlling invasive species on their own property and if the infestation spread to an adjacent land, you had to stop controlling at the boundary,” said IDNR regional administrator Jody Shimp. “Now, through the River to River CWMA partnership, we can work together to take the steps necessary to get the invaders under control, on both sides of the fence.”

The CWMA is trying to reach out to everyone in Southern Illinois.

“Many people recognize the problem of invasive species, but don’t realize that they can help out,” says CWMA Coordinator Chris Evans. “We want to work with these folks and anyone else in the area on how best to battle these invasive plants.”

What are some ways to help with the fight against invasive species? Here are a few suggestions from the CWMA:

Control invasive species on your land. Begin as soon as you find an invader. Controlling small infestations is more effective and economical than trying to control a well-established, rapidly spreading infestation.

Know your plants. Find out which plants cause problems in parks or natural areas in your region to know which species to avoid.

Use non-invasive alternatives. Many of the worst invaders are still being sold at nurseries. Ask a nursery about non-invasive plant alternatives. Native plants often have similar characteristics to invasives without the damaging ecological side effects.

Don’t spread invasive species. The tiny seeds of many invaders can hitch a ride on hiker’s shoes, angler’s boats, or even the tires of your bicycle. If you go into an area with invasive species, clean off all soil or plant matter from your equipment and clothes before leaving.

Don’t empty aquariums or dump houseplants into the wild. Some of the worst invaders started off as exotic ornamental plants.

Volunteer with local natural resource agencies to control invasive species. The time and services generously donated by volunteers are an important part of the fight against invasive species.
Spread the word! Tell a neighbor about invasive species.

To find out more about invasive species or the Cooperative Weed Management Area, contact Chris Evans at 618-998-5920 or RivertoRiver@gmail.com