February 2016
6th Texas Invasive Plant and Pest Conference - Reminder!

Early-bird registration is closed but you can still register for the conference! The schedule will be available soon.

To register and for more information on the Conference, Call for Papers, Abstract Submission, Sponsors and Exhibitors, Lodging, Continuing Education Credit, Student Travel, etc., please visit the Conference website.



Texas Gulf Region CWMA Brazilian Peppertree Removal

The Texas Gulf Region Cooperative Weed Management Area (TGR-CWMA) held a work party on February 24 to remove the invasive Brazilian peppertree (Schinus terebinthifolius) from the University of Texas Marine Sciences Institute (MSI) property. Over 20 people from the City of Port Aransas, the MSI, Texas Parks and Wildlife Department, Texas A&M Forest Service, the UT-Lady Bird Johnson Wildflower Center, among other organizations and volunteers, worked to clear several trailer-loads of trees. What was most impressive was the bare ground exposed by removing the trees, illustrating how much they crowd out the native coastal prairie plants.

The TGR-CWMA also held its biannual meeting to discuss, among other things, the draft 5-year management plan, funding, and accomplishments.

For more information on the Brazilian peppertree, go to Texasinvasives.org.

TGR-CWMA BP removal1

TGR-CWMA BP removal2

Photo credit: Hans Landel, LBJWC

Texas Envirothon Competition - Reminder!

The Texas Envirothon will be held April 2-4. Deadline for registration is March 4, 2016.
Please go to the Texas Envirothon website for complete information.

Envirothon logo


UHCL logo

Invasive Spotlight:
Asphodelus fistulosus)

Onionweed is a perennial herbaceous plant with leaves that resemble, as its name implies, onions or scallions: long, smooth, cylindrical, and hollow. However, they neither smell nor taste like onions. The numerous leaves are dark green and grow 12 to 30 inches tall from the base of the plant and spread to 15 inches wide. Onionweed produces one to several stiff upright, branched flower stem(s) up to 2 1/2 feet tall. The flowers alternate along the branches and are about three-fourths of an inch across with six petal parts, each white to pink with a brown or reddish stripe along the center. Fruits are spherical capsules divided into three segments. Seeds are brown or black, triangular, one-eighth inch long, wrinkled, pitted and three or six per fruit. The thick root crowns have many fibrous roots and no developed bulb.

Onionweed is native to the Mediterranean area and from western Asia to India. It was introduced in the United States as an ornamental. It is an aggressive invasive, seeding prolifically and spreading relatively rapidly. It excludes grasses and desirable forbs.

Because onionweed infestations pose a serious risk to ecosystems as well as agriculture, it is currently on the Federal and the Texas Department of Agriculture noxious weed lists. 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 Texasinvasives.org website and reporting app.

Onionweed has occasionally been found in Texas, but there have not been any reported infestations. Let's keep it that way! If you believe you have found onionweed, please report this species.

Follow this link for more information on onionweed.


Source: USDA APHIS PPQ - Oxford, North Carolina , USDA APHIS PPQ, Bugwood.org

onionweed flowers

Credit: John Ruter, University of Georgia, Bugwood.org

onionweed_map 5

More News

Carrizo Cane, a Threat to National Security, Controlled with Biocontrol
The invasive, aggressive Carrizo cane not only displaces natural plant communities and habitat along the Rio Grande, it also creates a headache for border patrol agents trying to stem the flow of illegal contraband and immigration along the river. However, with the help of the USDA-ARS, a wasp (Tetramesa romana) now holds promise as a tool for controlling the cane. Learn more about how the Carizzo cane acts as a hideout and how the wasp controls the cane's growth at Texasstandard.org.

Texas Researchers Use Flies in Attempt to Control Fire Ants
Researchers from UT, with the help of the USDA and Quilmes University in Argentina, are using the invasive South American fire ant’s natural predator, phorid flies (Pseudacteon species), in an attempt to control the ant (Solenopsis invicta) in Texas. A phorid fly will lay an egg inside a single ant, which will then isolate itself and die as the larva develops and then emerges as an adult. While singling out a few individuals from a colony will not reduce the population directly, one phorid fly is all it takes to affect the feeding behavior of an entire colony. The researchers are hopeful that over time this will reduce the number of fire ant colonies and allow native species to recover. Learn more about the control efforts.

US Forest Service Releases Findings on the Effects of Drought on Forests, Rangelands
The US Forest Service has released a new report that provides a national assessment of peer-reviewed scientific research on the impacts of drought on US forests and rangelands. Among the topics discussed are the effects of invasive species. “Droughts are predicted to accelerate the pace of invasion by some nonnative plant species into rangelands and grasslands” both directly and indirectly, including through the effects of drought on wildfire. This report will help the Forest Service better manage forests and grasslands impacted by climate change.

Signal Crayfish Threaten Crater Lake
The crystal clear waters of Crater Lake, the deepest lake in the United States, are under threat from the signal crayfish (Pacifastacus leniusculus). Although the National Park Service brought the crayfish in to feed the introduced bass and trout populations in 1915, it wasn’t until 2014 that surveys started in 2008 showed a boom in population. The crayfish feed on everything from snails to caddisflies and are threatening the lake’s once keystone predator, the Mazama newt (Taricha granulosa mazamae). Conservationists are left searching for ways to defend the newts and Crater Lake’s other denizens from the advancing signal crayfish. Learn more about the Mazama newt, Crater Lake and conservation efforts.

Using Math to Understand White-nose Mortality
Mathematical modeling has shown that bat mortality rates linked to white-nose syndrome can be affected by hibernation site conditions. The study compared mortality rates of North American bats with continental European bat populations. It also noted that bats using caves or hibernation sites that were cold and dry fared better than species relegated to warmer and moister hibernation sites. The practical implications of this research may permit predicting which populations and species are at risk of decline. Learn more about the study.

Dogs, Drones and DNA
From cutting-edge technologies like drones and phone apps to highly accurate dog noses and the use of environmental DNA, a recent invasive species forum held in Richmond, B.C., showcased novel techniques empowering experts in the battle against invasive species. These new approaches to invasive species management are fast becoming “game changers”. Read more about the forum and how these new approaches are helping experts in the field.

Stopping the Asian Toad Before It's Too Late
Scientists are warning Madagascar to eradicate the Asian toad (Duttaphrynus melanostictus), a recent invasive species, before it's too late. The Asian toad, a rapidly reproducing toad native to Southeast Asia that is compared to the cane toad (Rhinella marina), is toxic to birds, mammals, and snakes and has the potential to disrupt the island food chain. Currently the toad population is confined to the port city of Toamasina but if it reaches the Pangalanes canal system, eradication would become impossible. Learn more about current eradication efforts.

Rainforest Logging Expands Black Rat Territory
Inadvertently spread around the world by Europeans, the black rat (Rattus rattus) has been a common invasive species since the 1600's. Researchers have begun studying the effects of rainforest logging on the movements of the invasive rat. While the rats have long become residents of the urban centers of Borneo, the study shows that the black rat is now making its way into rainforest habitat where recent logging activity has created optimal black rat "micro-environments". Read more about the effects of logging on forest structure and the creation of black rat habitat.

Ancient Parasite Poses Huge Risk to Freshwater Fish
The Asian gudgeon (Pseudorasbora parva) hides an ancient parasite called Sphaerothecum destruens, a relict from an age when animal and fungal organisms began to differentiate. The Asian gudgeon is a healthy vector for S. destruens, which has an 80-90% mortality rate among other freshwater fish species. The Asian gudgeon has devastated European and North African rivers and has been found in some North American salmon. More alarmingly, the parasite has been found in a brackish aquaculture farm in Turkey that is used to cultivate bass. Read more about the gudgeon and the ancient, devastating parasite it carries.

Human Trade Key in the Spread of Bee Pandemic
New research has shown that Deformed Wing Disease and the Varroa mite (Varroa destructo), which have decimated honey bee populations around the world, are mainly spread by human trade. Genetic sampling of the virus and the mite have shown the pandemic originated in Europe and then spread to North America, Australia and New Zealand. DNA sampling between regions and other related species are pointing to human trade rather than natural dispersal as the main mode of pandemic transmission. Learn more about the honeybee pandemic and the evidence for manmade transmission.

The Ecology of Climate Change
Using herbarium specimens from 35 herbaria throughout California, researchers are creating a picture of how climate change is affecting native California plants. They are finding that a combination of factors such as seed size, obstacles like human development, changing bird migration and the presence of invasive species are all playing a role in how plant communities are moving. Ecological communities are "breaking down and disassembling"; as these factors compound with climate change. Invasive species are able to move at a faster rate and may be colonizing new territories before native species can arrive. Read more about the ecology of climate change.

If you would like your invasive species event or news listed in the next iWire, please send the details to iwire@texasinvasives.org


Sentinel Pest Network and Invaders of Texas Species 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 Texasinvasives.org designed to help organize and track volunteer-based eradication efforts.

Upcoming Workshops:

Saturday, April 2, 2016
Location: Jesse H. Jones Park & Nature Center (Humble, TX)
Contact: Rosanne Belzung

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