July 2022
Alien Forest Pest Explorer

The Alien Forest Pest Explorer (AFPE) is a newly introduced interactive and customizable web tool developed by a group of researcher and developers at Purdue University, who partnered with the USDA Forestry Service. The AFPE offers maps of pest distributions, the growth, mortality and removal rates of host species, trends in host abundance, and information about the pests. The data will be updated annually to account for changes on the county level.

These dashboards are the first to overlay pest data with the status and health of the host tree species in the forest. It is designed to be user friendly for professionals and people of the public, so anyone can use it to determine if they have a pest infestation, how to identify them, and how to protect the trees and forest. It can be used to show the impact of different forest insect pests and diseases, and where there is potential for further damage. The AFPE has been integrated with the Northern Research Station's critical invasive species research with forest inventory and analysis data to enable users to view county-level data so the dashboards can be used for challenges posed by invasive insects at a local level.

The AFPE works by integrating two critical data sets and makes them available online with custom mapping options. The user can get information about the range of the invasive forest pest and the host, or hosts, in the forest. You can zoom in or out, draw an outline and isolate an area of interest, search by pest, see the amount of forest volume lost by a particular pest, and much more. The developers hope this dashboard will better assess the vulnerability of forests and lead to a better understanding of the relationship between pests and tree hosts.

Read more about the Alien Forest Pest Explorer.



 purdue-us-forest-servi-1The Alien Forest Pest Explorer interactive web tool shows the impact of different forest insects and diseases. Credit: Purdue University, Agricultural Communications.

forest damaged by forest pestsForest damaged by invasive forest pests. Credit: mapsweb.lib.purdue.edu

These Fish Hijack Sperm

The Prussian carp (Carassius gibelio), nicknamed the gibel carp, is considered one of the most successful invasive fish species in Europe. It is closely related to the goldfish and competes with the endangered native crucian carp. Prussian carp out compete other fish by reproducing asexually. The females use sperm of male crucian carps, or any other carp species, by intermingle with a swimming school where their laid eggs are fertilized by the males. The ‘hijacked’ sperm stimulates the Prussian carp egg cell to divide. The genetic material of the sperm is broken down in the egg cell without being used. This process is called sperm-dependent parthenogenesis. All offspring produced through this process are female clones of the mother. Males only occur rarely. Asexual, or unisexual, reproduction allows for rapid colonization, making this invasive species extremely successful at taking over new habitats.

A group of researchers studying the Prussian carp have been able to map out and describe the complete genome of the carp for the first time. They found the Prussian carp is hexaploid, meaning it has six sets of chromosomes. Four of these are believed to be from the crossing of unrelated fish, while two are added by crossing with closely related fish. The researchers propose that a problem occurred in the formation of the gametes at some point during these crossing, and this could be a trigger of unisexual reproduction. The reasoning for this is because in species that reproduce parthenogenetically, meiosis fails, and fusion of gametes is no longer necessary.

The analysis of the genome has provided a better understanding of where the peculiar reproductive method can form and provided additional research opportunities to answer questions regarding the invasive fish.

Read the research: Kuhl et al., 2022

Female Prussian carp. Kuhl et al 2022Female Prussian carp (Carassius gibelio). Credit: Kuhl et al 2022.

gibel carpUnisexual reproduction in Prussian, or gibel, carp. Credit: Fuad et al., 2021.

Battling Purple Loosestrife without Herbicide

Purple loosestrife (Lythrum salicaria) grows in dense patches of tall, angular stems crowded with pinkish-lavender flowers on top. These plants take over wetland habitats, easily outcompeting native grasses, sedges, and other flowering plants that provide a higher quality source of nutrition for the wildlife. Loosestrife has a long flowering season that utilizes pollinators to spread their many seeds. One mature flowering plant can have thirty flowering stems capable of producing upwards of three million seeds per year. Loosestrife also reproduces vegetatively through underground stems at a rate of about one foot per year. The highly invasive nature of these plants allows them to expand and establish quickly, forming dense stands that inhibit nesting sites by native wetland birds, as well as habitat formation for amphibians and turtles. It provides little to no viable habitat or food source for the wildlife.

After six years of research and intensive studies, Galerucella beetles (Galerucella calmariensis and G. pusilla) were introduced to North America as part of a purple loosestrife control program. This beetle is native to Eurasia and has presented a preference to purple loosestrife as a host plant over any other native wetland plant, making it a valuable biological control agent. A single female Galerucella beetle can lay up to 400 eggs in a lifetime. Over time with a large enough population of beetle, a whole stand of purple loosestrife can become defoliated. The larvae feed on the underside of leaves, eating the photosynthetic tissue creating a ‘window-pane’ effect, while adults eat straight through the leaves and shoot tips.

It generally takes 3-5 years after Galerucella beetles are introduced before a significant difference can be seen in the purple loosestrife populations. Complete eradication generally cannot be achieved; however, maintaining a population of Galerucella beetles can prevent purple loosestrife from spreading and overtaking large areas. This biocontrol can offer an option of control without herbicides.

Purple loosestrife (<em>Lythrum salicaria</em>). Leslie J. Mehrhoff. University of Connecticut
Purple loosestrife (Lythrum salicaria). Credit: Leslie J. Mehrhoff, University of Connecticut, bugwood.org.

golden loosestrife beetle (Galerucella pusilla). Agriculture and Agri-Food Canada
Golden loosestrife beetle (Galerucella pusilla). Credit: Agriculture and Agri-Food Canada, bugwood.org.

black-margined loosestrife beetle (Galerucella calmariensis) damage to purple loosestrife. Bernd Blossey. Cornell University
Damage to purple loosestrife by black-margined loosestrife beetle (Galerucella calmariensis). Credit: Bernd Blossey, Cornell University, bugwood.org.

Invasive Algae at Jones Lake

Over the past two years, the City of Lufkin has struggled with the removal of several species of invasive algae from Jones Lake. The warm summer months create the ideal growing conditions for the algae, allowing it to grow faster than it can be removed. The city has initiated many different removal techniques, but none have worked as well as hoped. They first tried hiring a company to physically remove the algae and treat the water to prevent it from growing back as quickly. When this didn’t work, they introduced algae-eating tilapia and added aerators. The tilapia did not eat the algae faster than it grew. The algae returned and clogged the aerators. The Lufkin Parks and Recreation is struggling to keep them going. The city now plans to partner with scientists from Stephen F. Austin University, who will run additional water tests and strive to identify the specific species of algae. The city hopes this new information will lead to the implementation of a new removal technique that will beautify their lake.

algae in jones lake. city of lufkin
Invasive algae in Jones Lake. Credit: City of Lufkin.

Drought Affects Lake Travis

The recent high temperatures and low rainfall have caused the water level to drop in many central Texas lakes, including Lake Travis. Lake Travis has been infested with invasive zebra mussels (Dreissena polymorpha) since 2017. These drought conditions are both good and bad for the zebra mussel infestation. Good news: as the water level declines, many of the mussels stranded on the dry areas are left to die. Although the shells of dead mussels are sharp and potentially hazardous to the public, once exposed, they can be scraped off, removed, placed in black trash bags and properly exposed of. Bad news: the remaining zebra mussel population has access to new areas to colonize now that the water levels in the lake have changed. The mussels that were lower along the water shed are not affected and will continue to propagate and spread as usual. Higher temperature, lower water levels, and drought conditions will not rid the lake of mussels. While there is nothing officials can do to rid the lake of invasive mussels, locals can work together to clear the shores of dead mussels, keeps docks and boats clean to slow the spread through Lake Travis, and Clean, Drain, Dry to prevent spread to other water ways.

  zebra mussels in lake travis. abc news
Zebra mussels in Lake Travis. Credit: abc news.

Emerald Ash Borer Watch

The presence of the invasive emerald ash borer (EAB, Agrilus planipennis) has been confirmed in two new Texas counties, Morris and Rusk County. EAB is now confirmed in 11 Texas counties: Bowie, Cass, Dallas, Denton, Harrison, Marion, Morris, Rusk, Wise, Parker, and Tarrant.

Morris and Rusk County, as well as all counties with a confirmed EAB presence, have been added to the list of Texas jurisdictions under quarantine by the Texas Department of Agriculture. These quarantines are designed to restrict the movement of any woody ash material leaving the quarantine area in order to limit or slow the spread of the invasive pest insect. The rapid spread of EAB is detrimental to ash tree populations and can result in the death of millions of trees.

The emerald ash borer is a metallic emerald-green beetle with an iridescence coppery or reddish reflection. The adult beetle is bullet shaped (10-13 mm) and has a characteristically bright red to purple coloration on its abdominal surface under its wings (elytra). One external sign of EAB infestation is the distinctive D-shaped hole adult EABs leave in the trees upon emergence. The larvae are white, and slightly flattened, with a pair of brown pincher-like appendages on the last abdominal segment. The larvae (1.5 in) feed on the phloem and outer sapwood of ash trees, leaving S-shaped galleries that cut off the circulation of phloem to the tree, resulting in tree death.

If you believe you have seen an emerald ash borer, please take a picture and REPORT IT! here.

 EAB Watch 
Kylee N. Kleiner, TRIES.

North American Invasive Species Management Association Training Webinars

This program is designed to provide the education needed for professionals and students who are managing or learning to manage invasive species. The courses include the most current invasive species identification, control, and management techniques, and how to comply with local and federal regulations.

Participants may register and enroll at any time, and will receive a certificate of invasive species management from NAISMA upon completion of the program.

All live webinars are open to the public. Recorded webinars are available to members of NAISMA.

NAISMA 2020 Webinar Schedule:

  • August 17, 1pm- How to get your project funded. REGISTER.
  • September 20, 1pm- Utilizing fire and grazing to manage invasive perennial grasses. REGISTER.
  • October 19, 1pm- Invasive plant management on non-industrial forest lands in the panhandle, FL after hurricane Michael. REGISTER
  • November 16, 1pm- Invasive mussel collaborative tools and accomplishments. REGISTER.



The North American Invasive Species Management Association (NAISMA) is excited to announce the launch of InvasivesU, an exclusive online learning library intended to provide professionals, students, and individuals with the knowledge and tools necessary to prevent and manage invasive species in North America. The different courses consist of video presentations contributed by experts, along with supplemental materials for learning and assessment. Available online courses are available for a small fee or free for members. More information about InvasivesU.

InvasivesU. Credit: NAISMA.com

Invasive Spotlight:

Sirex Woodwasp
(Sirex noctilio)

The sirex woodwasp (Sirex noctilio) is a species of horntail, named for the spear-shaped plate (cornus) at the tail end. It is a large, robust insect, usually 1.0 to 1.5 inches long. In general, its body is a dark metallic blue or black, although in males the middle segments of the abdomen are orange. Its legs are reddish-yellow, its feet black, however, the hindlegs of males are thickened and black. Its antennae are entirely black. Females have a long ovipositor under the cornus. There are many native woodwasps, so positive identification of S. noctilio needs to be confirmed by an insect taxonomist. Larvae are creamy white, legless, and have a distinctive dark spine at the rear of the abdomen. They create tunnels, or galleries, in the wood under the bark. When adults emerge after pupating in the wood, they chew round exit holes that are from 3 to 8 mm (1/8 to 3/8 in) wide.

The sirex woodwasp feeds on healthy pine trees. Females drill holes through the bark to lay their eggs in the wood. While drilling, they inject a toxic mucus and a symbiotic fungus (Amylostereum areolatum), which together kill the tree while creating an environment in which the larvae can thrive. It has the potential to cause extensive damage across North America. The sirex woodwasp attack live trees, while native woodwasps only attack stressed, dying and dead trees. Foliage of infested trees initially wilt, and change colors from dark green to yellow, and finally to red during the 3-6 months following an attack. Infested trees may have resin beads or seep at the egg laying sites.

To learn more about the sirex woodwasp, visit the TexasInvasives info page. Because of its potential negative impact in Texas, the sirex woodwasp has been listed as a Report It! species as part of the Sentinel Pest Network. If you believe you have found a sirex woodwasp, please REPORT IT! here. There are many native horntail wasps that can be confused with the sirex woodwasp. Please provide a specimen with your report to aid in identification. Don't worry, they don't sting.

Sirex woodwasp (Sirex noctilio). female on left. male on right. Vicky Klasmer
Sirex woodwasp (Sirex noctilio). Female on left, male on right. Credit: Vicky Klasmer, bugwood.org

 Resin dribbles from oviposition wounds in 14 yr old tree. Dennis Haugen. 
Resin dribbles from sirex oviposition wounds in 14 yr old tree. Credit: Dennis Haugen, bugwood.org

Larval galleries in board sawn from a sirex-infested tree. Dennis Haugen
Larval galleries in board from sirex-infested tree. Credit: Dennis Haugen, bugwood.org

Get Involved Today!!

The Texas Invasive Species Institute (TISI) and The Texas Research Institute for Environmental Studies (TRIES) has many surveys and projects underway. These facilities strive to provide yearly invasive species presence and absence data to the authorities. Pre-screening is one of the first lines of defense in the war against invasives. However, sometimes it is hard to do it alone.

With the aid of the public and citizen scientist, we could cover a much wider area, and gather a more substantial amounts of data. When it comes to protecting our environment, there is an opportunity for everyone! Together we can make a difference, one research project at a time.

See how you can get involved by reading the projects listed below or see all the available projects on the Texas Invasives website HERE.

Citrus Greening Workshops

We need your help to safeguard Texas Citrus, and it can start in your backyard!

TISI is offering educational workshops focused on the Asian citrus psyllid and the pathogen Citrus Greening. The Asian citrus psyllid and the Citrus Greening pathogen is threatening citrus in multiple Texas counties, and we need your help to monitor the spread. The workshop will highlight what you need to look out for, address USDA-APHIS Citrus Quarantines, and offer diagnostic services if you suspect your backyard citrus has either the psyllid pest or Citrus Greening pathogen. This includes providing trapping materials, assisting with management strategies, and more.

Please contact invasives@shsu.edu so we can schedule a workshop (virtual or in-person) for you or your group this year!

Aquarium Watch: Looking for Prohibited Invasive Aquatic Species

Please help texasinvasives.org and natural habitats by looking for 14 prohibited invasive aquatic species being sold in your local aquarium store. With just one photo you can assist us in finding and documenting which stores are selling prohibited species. Texasinvasives.org will contact the appropriate Texas institutions to remove the species for sale.

If you would like more information please email invasives@shsu.edu, and mention you want to assist with our Aquarium Watch.

Air Potato Survey

Help Texas Research Institute for Environmental Studies conduct an air potato survey by actively reporting any infestations seen in your area. The air potato (Dioscorea bulbifera) is a fast growing, high climbing vine. Potato-like tubers are the primary means of reproduction for this vine. They can be as small as a marble or as large as a softball. Native yams are often confused for air potatoes, to avoid this confusion please refer to the key below:

- Plants rhizomatous; bulbils never produced in leaf axils; petiole base never clasping the stem; Native D. villosa
- Plants tuberous; bulbils produced in leaf axils; petiole base sometimes clasping the stem; Invasive D. bulbifera

For additional information, please refer to the TexasInvasives information page.

If you believe you have identified an air potato vine, please email invasives@shsu.edu and include the following information: an image, an approximate number of vines present, the location (including whether it is on public or private land), and if bulbils are present (the potato-like tubers that emerge from the stem).

Participation opportunities
Participation Opportunities. Credit: KNKleiner, TRIES.

Citrus greening. JM Bove
Leaf mottle on grapefruit, a characteristic symptom caused by citrus greening bacterium but also seen on trees infected by Spiroplasma citri. Credit: J.M. Bove.

Armorded catfish. Photographer United States Geological Survey
Armored catfish (Hypostomus plecostomus). Credit: United States Geological Survey.

air-potato (Dioscorea bulbifera)2 bulbil. credit Karen Brown
Air-potato (Dioscorea bulbifera), bulbil emerging from leaf axil. Credit: Karen Brown.

More News

Dallas Park Department Finds Poisonous Water Hemlock at White Rock Lake
Toxic water hemlock (Conium maculatum) has been found in one of Dallas’s local parks. The recreation department has made it their top priority to eradicate all signs of this invasive plant by applying pesticide. dallas.culturemap.com

The Stages of Invasion: How Does a Nonnative Species Transition to An Invader?
A research paper that uses Florida as an example to explain how nonnative species can become established invasive species by moving through five stages of human-aided biological invasion. edis.ifas.ufl.edu

Peter Dykstra: American Invasive Species Hall of Fame, Part 1 And Part 2
Here are two lists that make up one man’s opinion of the flora and fauna that have left their mark on North Americas natural ecosystems to such a degree that they have made it to the “invasive species hall of fame”. Part 1. Part 2.

A Florida County Is Quarantining After Discovery of Invasive Giant African Land Snail
The New Port Richey area of Pasco County is under quarantine due to the discovery of a population of invasive giant African land snails (Lissachatina fulica). The snails pose a public health risk, populate quickly, and are fast growing. cnn.com

Concerned About Native Biodiversity, Volunteers Join the Fight Against Invasive Alien Species
Researchers investigated the motivations behind committed volunteers engaged in invasive species eradication programs. They looked at how motivation changes over time and how this could be used to find volunteers and strengthen teams for programs in the future. phys.org

A Successful 'Copi' Rebrand of Invasive Asian Carp Promises Economic and Ecological Benefits for The Peoria Region
Illinois officials are rebranding four invasive species of Asian carp by renaming them “copi”. The hope is that the new branding will help make the fish more desirable to eat, bulk up processing and distribution. This fish is quickly out competing native fish populations in local waterways and increased processing and consumption could reduce some environmental stress. wcbu.org

Artist Teaches How to Turn Invasive Japanese Knotweed into Crafting Material
Local man teaches how to turn invasive trees and plants like Japanese knotweed (Fallopia japonica) in to crafting items, like paper. He explains how knotweed is also edible and can be turned into a delicious honey or eaten as is. triblive.com

New Disease Strikes Michigan Trees. Arborists Don't Know How to Treat It
Beech leaf disease, an invasive disease associated with the nematode Litylenchus crenatae mccannii, has hit a stand of southeast Michigan trees, adding to a long list of threats faced by state forests. phys.org

Catching Invasive Species in Hawaii, Why It Matters
Most accidently introduced animals become detrimental to Hawaii’s environment. Officials said a new species of pest is found every month and while they are mostly insects, reptiles are also a point of focus. khon2.com

Genetically-Enhanced Biocontrols Can Help Fight Large Invasive Mammals, Study Finds
Genome engineering using CRISPR may offer a novel solution for controlling invasive species, but its efficiency for eradicating harmful vertebrates is still untested. In a new study, researchers confirm that genetic biocontrols could rapidly eradicate animals like rats, mice and rabbits, but larger vertebrates would take a very long time. sciencedaily.com


Sentinel Pest Network and Invaders of Texas Workshops

Invaders of Texas workshops train volunteers to detect and report invasive species as citizen scientists. Workshops, which are free, are designed to introduce participants to invasive species and the problems they cause, cover aspects of invasive species management, teach identification of local invasive plants, and train participants to report invasive plants using the TX Invaders mobile application. The workshop is 7 hours long (usually on a Saturday, but scheduling is arranged with each individual host group). The workshop satisfies Master Naturalist training requirements.

Sentinel Pest Network workshops serve to increase the awareness and early detection of a set of particularly important invasive species to help prevent their spread into Texas or their further spread within Texas. Participants learn to identify species such as the Emerald Ash Borer, Cactus Moth, Asian Longhorned Beetle, and other pests of regulatory significance, and to report them. The workshop is 3.5 hours long. The workshop satisfies Master Naturalist training requirements.

Upcoming Workshops: