November 2018
Texas Aquatic Plant Management Society Meeting Held in San Antonio

The Texas Aquatic Plant Management Society (TAPMS) annual meeting was held in San Antonio at the end of November. TAPMS consists of aquatic vegetation management professionals, companies, researchers, students, and Extension specialists dedicated to the aquatic vegetation management issues in Texas, and is the Texas sub-unit of the Aquatic Plant Management Society, Inc. The presentations were very informative. Their topics ranged from updates by Texas Parks and Wildlife Department personnel on integrated invasive aquatic plant management in Texas, to an overview and update on state and federal laws and regulations covering the use of herbicides in the management of aquatic plants, to results of research on various herbicides and on the management of various aquatic invasives, to tips on how to minimize drift when applying herbicide. Andrew Howell, a Ph.D. student from North Carolina State University, gave two very interesting presentations, one on the use of small Unmanned Aircraft Systems (sUAS) and one on the development of an unmanned autonomous boat that could both be used to map and treat invasive plants. He won the award for the best student research--congratulations! During the meeting, new officers were elected. The meeting next year will be held in the Fall in College Station, so plan ahead to attend.


How Invasive Earthworm Feces Is Altering US Soils

The earthworms you encounter in your garden or in natural areas are typically not native to North America, especially if you live in the northern United States. In those areas, earthworms were apparently pushed out by the last glaciation. Most U.S. earthworms are non-natives; that night crawler, Lumbricus terrestris, that you buy for your fishing line is from Europe. The non-native species compete with natives but especially they change the nutrient cycling in northern North American forests by processing detritus on the forest floor more quickly than would normally occur (see also here and here).

Recent research has begun to discover how Asian jumping earthworms (Amynthas agrestis, among others) are directly impacting soil. Geoscientist Jenelle Wempner of the University of Wisconsin in Madison has found that the earthworm's fecal material, which looks like "coffee grounds", "lock up nutrients and chemically alter the soil composition", making it more difficult for plants to access the nutrients.

Read more at In addition, here is a fact sheet on Asian jumping worms, and a video that illustrates why jumping worms potentially have a larger ecological impact than other non-native earthworms.

Asian jumping worm. Note the prominent whitish clitellum (ring near the head) that is flush with the body. They do not burrow very far into the soil, but instead are typically in the leaf and detritus layer of the soil. Credit: University of Wisconsin Arboretum

Senate Passes Bill to Help Keep Invasive Species Out of Great Lakes

The United States Senate recently passed the Vessel Incidental Discharge Act. This new law "establishes a framework for the EPA and the Coast Guard to establish national rules on ballast water and incidental discharge. Currently, discharges are regulated through different state permits under Section 402 of the Clean Water Act, creating a patchwork of state permit requirements in 26 states. Under the bill, the EPA will have the lead role in establishing national standards for discharges, while the Coast Guard will have the primary role for monitoring and enforcing these standards and ensuring vessel safety." Because many invasive species have spread by being carried in ballast water, standardizing the way ships are allowed to discharge ballast water could help to minimize the spread of invasive species. However, the bill also "preempts states from adopting standards that are stronger than federal law." This means it is very important that the states very carefully review the proposed national rules.


ship ballast illustration
Great Lakes map

New Boat Designs Could Help Stop Spread of Aquatic Invasive Species

Watercraft play a big role in spreading aquatic invasive species. When a boat is transported from a water body infested with invasive species, it could inadvertently carry some of those species to an uninfested water body. The common way to reduce the probability that a boat carries invasive species is to CLEAN-DRAIN-DRY. A graduate student from the Minnesota Aquatic Invasive Species Research Center, Adam Doll, is working on an additional approach: designing boats to reduce the spread of zebra mussels (Dreissena polymorpha). He has been looking for the microscopic zebra mussel larvae, called veligers, in samples of water he collected from compartments in watercraft, including motors, ballast tanks, and live wells. While he found that the veligers don't survive long in boats out of water, he did conclude that the number of veligers could be reduced by designing boats to drain better and with sealed compartments.


Drain Boat

Invasive Spotlight:
(Imperata cylindrica)

Cogongrass (Imperata cylindrica) was originally introduced from Southeast Asia to Southeastern United States in the early 20th century for soil stabilization. Parts of Alabama, Florida, Louisiana and Mississippi are now heavily infested, with the grass spreading as far west as Texas and as far north as North Carolina. It is ranked as one of the ten worst weeds in the world.

Cogongrass requires full to partial sun, which allows the grass to take over pastures, meadows and even wooded areas quickly. This perennial grass utilizes disturbed ecosystems such as rights of way as well. It spreads via white, scaly rhizomes that create dense circular mats. The stiff leaves grow up to 4 feet in height and an inch wide, have finely serrated margins and an off-centered white midrib (see picture at right), are covered in hairs on the upper surface at the base (see picture at right), and terminate in a sharp point. Silky white flowers form on a panicle that can reach up to 11 inches long.

Cogongrass produces thousands of tiny tufted seeds that resemble dandelion seeds and are carried by wind. Both rhizomes and seeds can be carried to new sites via contaminated soil and equipment.

The dense mats of cogongrass prohibit the growth of other plant species and create a serious fire hazard as they alter the normal fire regime of a landscape. Fires burn hotter and occur more frequently where cogongrass is present, which can destroy native plant species, displacing native animal and insect species by eliminating food sources, shelter and nesting sites.

Because cogongrass infestations pose a serious risk to ecosystems as well as community safety, it is currently on the Federal noxious weed list and is either classified as a noxious weed, quarantined or prohibited in the states of AL, CA, FL, HI, MN, MS, NC, OR, SC and VT. It is also one of the “Dirty Dozen” pest species identified by the Texas Invasive Plant and Pest Council. Therefore, it is one of the “Report It!” alert species on the website and reporting app.

If you believe you have found cogongrass, please report this species using the website or the mobile app.

Follow this link, this link (pdf), or this link for more information on cogongrass, including its identfying characteristics.


Photographer: Charles T. Bryson
Source: USDA Agricultural Research Service,

cogongrass leaf stripe

Credit: Mark Atwater, Weed Control Unlimited, Inc.,

cogongrass leafhairs

Credit: Chris Evans, University of Illinois,

cogongrass plant  cogongrass seedhead
Left: Karan A. Rawlins, University of Georgia,
Right: John D. Byrd, Mississippi State University,

cogongrass map

More News

Floating Machine Removes Invasive Aquatic Plant in San Francisco Lake
San Francisco Recreation and Parks Department is using a new specialized piece of equipment, called an Aquamog, to clear out the invasive aquatic plant water primrose (Ludwigia spp.). "With the treads and claw you might think it's a backhoe but then it pushes off and starts floating out into North Lake in Golden Gate Park, it's claw pulling huge clumps of the invasive plant out by the root." Read more and see a video at

Group Develops Plan to Combat Invasive Species Along Hudson River
Here is another example of a number of stakeholders forming a group to combat invasive species, in this case along the Lower Hudson River. They will develop an action plan for management of aquatic invasive species. Read more at

Chicago River Advocates Get Grant to Clear Invasive Species
Friends of the Chicago River received a grant of over $240,000 to remove invasive species and plant native grasses along a creek near Chicago. Read more at

Understanding Issues in Enforcing Invasive Species Laws
The 2018 Montana Invasive Species Summit convened in Helena this week bringing together policy makers and enforcers to examine success and potential improvements in Montana’s effort to combat invasive animals and plants. Among the programs Friday was a panel featuring law enforcement and legal experts discussing the role officers and courts play in levying punishments for violating invasive species’ laws. Read more at Click here to visit the Summit website, which includes links to the presentations.

Goats Help to Control Invasive Plants
Goats (Capra aegagrus hircus) are being used in Arkansas to manage invasive plants. [Note that the article is incorrect when it says that goats are "the best way" to remove invasive species (they won’t control invasive animals!), since many plants will simply resprout. Goats are a tool in the management toolbox.] Read more at

Indiana Bans Sale of Two Aquatic Invasive Species
Indiana has banned the sale and distribution of two invasive aquatic plant species: starry stonewort (Nitellopsis obtusa), which is causing problems problems already, and water soldier (Stratiotes aloides), which is not found in the state yet. Read more at

South Africa’s Invasive Species Guzzle Water and Hurt the Economy
"The country’s pioneering first report on its biological invaders paints a dire picture for resources and biodiversity… The invaders … cost the country approximately … US$450 million a year and are responsible for about a quarter of its biodiversity loss… Invasive species also guzzle a substantial amount of South Africa’s water, a serious problem in a country suffering from a prolonged and catastrophic drought that is expected to worsen as the climate changes." Read more at For more on the report itself, see this webpage.

New Tool to Predict Which Plants Will Become Invasive
"New research provides insight to help predict which plants are likely to become invasive in a particular community. The results showed that non-native plants are more likely to become invasive when they possess biological traits that are different from the native community and that plant height can be a competitive advantage. " Read more at

Australian Mammals at Greatest Risk From Cats and Foxes
Introduced fox (Vulpes vulpes) and feral cats (Felis catus) are threatening Australian native mammals with extinction. New research has revealed which Australian mammals are most vulnerable. Read more at


If you would like to highlight a successful invasive species project or nominate a special person to be highlighted in an upcoming iWire, please send the details to

Sentinel Pest Network and Invaders of Texas Workshops

Invaders of Texas workshops train volunteers to become citizen scientists to detect and report invasive species. Workshops, which are free, include information on the Sentinel Pest Network, which serves to increase the awareness and early detection of the Emerald Ash Borer, Cactus Moth, Asian Longhorned Beetle, and other pests of regulatory significance.

Workshops are tailored to meet the interests of your volunteer group, and supplementary session examples include an introduction to the TX Invaders mobile application and the Eradicator Calculator, a feature on designed to help organize and track volunteer-based eradication efforts.

Upcoming Workshops:

Sentinel Pest Network Workshop
Saturday, January 19, 2019

Location: AgriLIfe Extension Office, 607 North Vandeveer Street #100 (Burnet, TX)
Contact: Susan Montgomery

Saturday, February 2, 2019
Location: Mabee Library Auditorium, Headwaters of the Incarnate Word (San Antonio, TX)
Contact: Pamela Ball

For more information or to register to attend a free workshop, please visit the Workshop Page.