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Tropical soda apple (Solanum viarum), first detected in Australia in 2010, is a weed of agricultural significance as it reduces cattle stocking rates and limits stock movement. Gratiana boliviana (...

Earleaf acacia (Acacia auriculiformis A.Cunn. ex Benth) is a fast-growing, evergreen tree from Australia that was introduced into the United States as an ornamental plant, but it has become a serio...

Brazilian peppertree (Schinus terebinthifolia Raddi, Anacardiaceae) is an aggressive invasive species that occurs in peninsular Florida, USA. Current management techniques are expensive, require repeated application, and cause non-target damage in ecologically sensitive habitats. Calophya lutea Burckhardt and Calophya terebinthifolii Burckhardt & Basset (Hemiptera: Calophyidae) were found damaging Brazilian peppertree in Brazil. To determine if C. lutea and C. terebinthifolii are suitable biological control agents of Brazilian peppertree, host specificity testing was conducted in a quarantine laboratory. In total, 97 plant species were tested, and oviposition and gall initiation were evaluated under no-choice conditions. Calophya lutea and C. terebinthifolii oviposited on nine and five of the 97 plant species tested, respectively. The majority of the eggs were laid on Brazilian peppertree and complete immature development with adult emergence occurred only on Brazilian peppertree. Adult longevity and behavior were determined in a separated experiment on all non-target species on which Calophya oviposited during the host specificity experiment. Adult longevity was four to five times longer on Brazilian peppertree when compared to non-target species. Based on our results, we conclude that both C. lutea and C. terebinthifolii are host-specific and form galls and complete development only on Brazilian peppertree. Therefore, these agents are considered safe to release in Florida and should be incorporated into the ongoing biological control program.

Biological control is a sustainable method of weed management because agents can establish persistent and self-dispersing populations on a landscape scale. Strategic releases are often conducted to...

Lepidelphax pistiae Remes Lenicov (Hemiptera: Delphacidae) is monophagous on Pistia stratiotes L. (Araceae), an invasive floating plant in Florida. Temperature studies were conducted to determine the optimal temperature for development and reproduction for this potential biological control agent. Egg development time decreased as temperature increased from 17 degrees C to 30 degrees C. No eggs developed and no nymphs survived at 15 degrees C. Adult females survived the longest at 15 degrees C, indicating that they might be more resilient to cold temperatures. Optimal temperature for nymph development was 25 degrees C with 29% surviving to adulthood in 18.2 +/- 0.4 days. Public domain – authored by a U.S. government employee

Changes to the historical flow and nutrient levels of freshwater bodies in Florida have made control of waterhyacinth difficult. Biological control agents were introduced to augment herbicidal control of this plant. The newest insect agent, Megamelus scutellaris, was released in 2010, has established, and has been documented dispersing more than 6 kms away from release locations, across aquatic and terrestrial habitats. These insects were able to successfully disperse away from herbicide treated areas and across terrestrial habitats to reach new mats of waterhyacinth. Macropterous individuals were the first M. scutellaris documented at three non-release sites, indicating that the established wild populations are producing flighted individuals and are dispersing actively. Established populations appear to have reached an equilibrium density of 10.74 +/- 19.74 M. scutellaris/ m2 and this does not fluctuate with additional releases. Published version Public domain – authored by a U.S. government employee

Eichhornia crassipes (Martius) Solms Laubach (Liliales: Pontederiaceae) was introduced to Florida in the 1880s as an ornamental and it once infested thousands of square kilometers across the state. Megamelus scutellaris Berg (Hemiptera: Delphacidae) was developed as a classical biological control agent for this plant primarily because its free-living life stages allow it to better integrate with herbicides, which are currently used as the main control method for E. crassipes in Florida. Mass rearing and distribution programs can accelerate the benefits of biological control by augmenting natural dispersal, but an optimal release strategy must consider the entire system including the agent, the target weed, and the habitat. The effectiveness of various release strategies was evaluated using a tank experiment where single and multiple releases of either adult M. scutellaris only or E. crassipes infested with M. scutellaris eggs were compared to control treatments. The post-release dispersal capability of brachypterous M. scutellaris was evaluated using a linear transect of E. crassipes. Two density release treatments were tested and emerging nymphs were used as a proxy for female dispersal distances. All release treatments resulted in successful M. scutellaris population establishment and levels of M. scutellaris were not significantly different among them. The dispersal experiment indicated that adult females oviposit near the release point before dispersing. While the release experiment indicated that all treatments were similar, the continually fluctuating populations of E. crassipes makes establishment of populations difficult in the field. By releasing both adults and infested plants, additional propagule pressure can be attained from a single release event which can counter the tendency of adult M. scutellaris to disperse rapidly following release. Public domain – authored by a U.S. government employee

Pistia stratiotes L. (Araceae) is a floating aquatic plant that has become invasive in Florida. It is primarily controlled with herbicides, but two biocontrol agents have previously been re...

The Brazilian peppertree thrips, Pseudophilothrips ichini (Hood) (Thysanoptera: Phlaeothripidae), is an insect native to Brazil (Figure 1). This species has been studied for the last 20+ years as a potential biological control agent of Brazilian peppertree, Schinus terebinthifolia Raddi (Sapindales: Anacardiaceae), in Florida (Cuda et al. 2008; Cuda et al. 2008; Manrique at al. 2014; Wheeler et al. 2016a, b). Host specificity experiments demonstrated that Pseudophilothrips ichini has a limited host range (Cuda et al. 2008; Cuda et al. 2009; Wheeler et al. 2017) and can cause a severe reduction of Brazilian peppertree biomass (Manrique at al. 2014).https://edis.ifas.ufl.edu/in1270

Lilioceris cheni is a successful biological control agent on the invasive yam, Dioscorea bulbifera in many areas in Florida, Georgia, Alabama and Louisiana. Two biotypes are available for release and come from significantly different centres of origin. The Nepalese biotype was collected at higher altitude and latitude sites, whereas the Chinese biotype was collected at slightly lower latitude and lower altitude. We hypothesised that Nepalese beetles would survive winter better in north Florida and that Chinese beetles would overwinter better in subtropical south Florida. We established sites in Homestead, Fort Pierce, Gainesville and Tallahassee, Florida to gauge the overwintering survival of each biotype. Beetles that overwintered in each site for one to three seasons were collected and followed to assess their reproductive capacity. In the final year of the experiment, we extracted fat bodies to determine effects of biotype and site. Nepalese beetles overwintered significantly better overall. Be...

Integrating classical biological control with other management techniques such as herbicide, fire, mechanical control, grazing, or plant competition, can be the most effective way to manage invasive weeds in natural areas and rangelands. Biological control agents can be protected from potential negative impacts of these weed control methods through untreated refugia or by applying the treatment at a time when the agent is not vulnerable. A literature review of experiments that integrated biological control with other management strategies from 1987 to 2017 yielded 39 terrestrial and 16 aquatic studies. The tactics most frequently integrated with biological control were herbicide applications and plant competition. Despite numerous examples of successful programs and calls for more widespread integration of biological control with other weed management strategies, there was no increase in the number of studies reported annually over time. Additional studies investigating the ecological and economic benefits of integrated weed management are needed.

Classical biological control of waterhyacinth is difficult to evaluate against the backdrop of active herbicide programs. Two experiments evaluated the additive impact of herbivory by two biological control agents with three different rates of 2,4-D on waterhyacinth growth and development in outdoor concrete mesocosms. The herbicide 2,4-D was applied at three rates: (1) control (no herbicide), (2) reduced (2.1 kg ai ha-1), and (3) operational (4.3 kg ai ha-1). Biomass of waterhyacinth populations was reduced by 16.9% by biological control only, 10.5% by the reduced rate of herbicide alone, 44.6% by the operational rate, and 97.3% and 99.9% by the combination of biological control and the reduced and operational rates of herbicides, respectively. These results quantified the relative contributions of both tactics to waterhyacinth management and posit the question of whether further reductions in 2,4-D rates are possible without sacrificing efficacy.Nomenclature: 2,4-D; waterhyacinth, Eichhornia crassipes (Mart.) Solms.

Neochetina bruchi Hustache is commonly referred to as the chevroned water hyacinth weevil and is a weed biological control agent used to manage water hyacinth, Pontederia crassipes Mart. [formely Eichhornia crassipes (Mart.) Solms (Pellegrini et al. 2018)], in more than 30 countries (Winston et al. 2014). Imported from Argentina, the insect was first introduced into the United States in Florida in 1974 and released in Louisiana later in 1974 (Manning 1979), Texas 1980, and California 1982 to 1983 (Winston et al. 2014). Now Neochetina bruchi occurs throughout the Gulf Coast States (Winston et al. 2014). The target weed of Neochetina bruchi, water hyacinth, is an invasive aquatic plant in the United States and is included on Florida’s list of prohibited aquatic plants. Neochetina bruchi is among four species of insect biological control agents that have been introduced into the United States to manage water hyacinth. The other three species include a weevil, Neochetina eichhorniae; a moth, Niphograptaalbiguttalis; and a planthopper, Megamelus scutellaris, which were introduced into the United States in 1972, 1977, and 2010, respectively (Tipping et al. 2014). Although the larvae and pupae of Neochetina bruchi and Neochetina eichhorniae have similar appearance and behavior and can be difficult to differentiate by casual observation (Deloach and Cordo 1976), the adult stages of the two species of water hyacinth weevils can be distinguished relatively easily based on the color patterns on their elytra (hardened fore wings).

Includes: Introduction - Synonymy - Distribution - Description - Life Cycle - Hosts - Importance - Selected References This publication is also available on the Featured Creatures website at http://entnemdept.ufl.edu/Creatures/BENEFICIAL/alligatorweed_stem_borer.htm

Sometimes referred to as the ‘mottled water hyacinth weevil’, Neochetina eichhorniae Warner is a weevil that attacks the invasive, aquatic plant, water hyacinth, Eichhornia crassipes (Mart.) Solms. Water hyacinth is considered one of the most destructive plants in aquatic ecosystems in the United States and, as a result, is listed in both the federal noxious weed list and Florida’s list of prohibited aquatic plants. Neochetina eichhorniae is host specific and causes substantial damage to water hyacinth, making it a valuable biological control agent for this invasive weed in many parts of the world. The insect was first introduced into the United States from Argentina in 1972, when scientists released the insect in Broward County, Florida, to manage water hyacinth (Perkins 1973). Since then, the insect has been introduced in more than three dozen countries worldwide (Winston et al. 2014). Post-introduction studies indicate the insect substantially suppresses the growth of water hyacinth, significantly reducing biomass, flowers production, and water surface coverage (Grodowitz et al. 1991, Center et al. 1999, Tipping et al. 2014, Nesslage et al. 2016) and the need for herbicide applications (Haag 1986).

Brazilian peppertree is a nonnative invasive tree widely distributed in central and southern Florida. This fact sheet provides readers with the Brazilian peppertree history in Florida, habitats where found, identification, biology and control recommendations. The control recommendations in this fact sheet include traditional herbicide strategies as well as innovative new applications of biological control.

The Entomological Society of America's (ESA) Committee on Student Affairs organizes the student debate competition at the national meeting of ESA each year. The debate competition was specifically designed to increase the critical thinking skills in the student members of ESA, as well as to discuss contemporary issues about entomology that are of interest to people attending the annual meeting. The Entomology 2013 Student Debate Competition followed a slightly different format than that of previous years. Each topic was related to the theme of the meeting: “Science Impacting a Connected World.” Two of the topics were a traditional pro vs. condebate; the third posed a specific, globally significant problem and teams were challenged to describe and defend what they determined to be the most effective solution to ameliorate that problem. The topics were: Below, each of these topics is presented with an unbiased introduction followed by the solution-specific stances of each of the debating teams. ### Acknowledgements We thank Raghu Sathyamurthy, Richard Houseman, and Deborah Finke for their time and support, Anne Nielson for her guidance and support in organizing and running the debate competition, and Ivan Milosavljevic, Ashfaq Sial, Beth Choate, and George Hamilton for serving as judges for the competition. Unbiased introduction Jessica A. Hartshorn University of Arkansas Biodiversity is difficult to define, as it includes all genetic variation of all organisms, their communities, and their interactions. Biodiversity is being threatened in ways that have exceeded previous estimates. While the major debate is about the connectedness of the world causing threats to biodiversity, many would argue that it is our …

Spotted knapweed (Centaurea stoebe ssp. micranthos (Gugler) Hayek) is an invasive plant from Eurasia that degrades pastures and rangelands in the western United States and Canada. A biological control program for spotted and diffuse (C. diffusa Lamarck) knapweeds was initiated in the 1960s, with 13 species of insects introduced and established in the United States and Canada. The program has largely been considered a success and Larinus minutus Gyllenhal (Coleoptera: Curculionidae) is considered to be one of the key agents responsible for the reduction of knapweeds. Spotted knapweed expanded its range into the southeastern United States, but biological control was not used against the weed in this region until recently. Larinus minutus were released in 6 counties in Arkansas from 2008 through 2012. Weekly sweep-net sampling to monitor weevil activity showed establishment of the weevils in 5 counties. The numbers of L. minutus captured at each site increased from 2010 to 2012. Larinus minutus in Arkansas was univoltine and sex ratios were 1:1, except during flowering, when the proportion of females captured increased. Eggs were not present in females until 1 week after flowering of spotted knapweed.

Summary A native parasitoid, Kalopolynema ema (Schauff and Grissell) (Hymenoptera: Mymaridae), has begun utilizing a new host, Megamelus scutellaris Berg (Hemiptera: Delphacidae), the introduced biological control agent for waterhyacinth, Eichhornia crassipes (Mart.) Solms (Commelinales: Pontederiaceae). Parasitism rates varied between outdoor M. scutellaris rearing tanks and sentinel plants placed in the field, with parasitism rates in the tanks being higher.

Larinus minutus Gyllenhal (Coleoptera: Cur culionidae) is a univoltine weevil that feeds on the seeds of spotted and diffuse knapweeds Centau rea stoebe ssp. micranthos (Gugler) Hayek and C. diffusa Lamarck. After emerging from overwin tering sites in the leaf litter, adult weevils begin feeding on the vegetative portions of the plants. Adults, however, prefer to feed on flowers when they are available and development of beetle ova ries is dependent upon flower feeding (Groppe 1990). Females oviposit on newly opened flower heads (capitula). Two or 3 eggs can occur in each flower head, but only 1 larva usually develops in smaller capitula. Multiple larvae can survive in large spotted knapweed capitula (Groppe 1990). Under laboratory conditions (25°C), eggs hatch in 3-4 d (Groppe 1990). Larval development takes approximately 4 weeks and larvae go through 3 instars. Larvae feed on knapweed seeds and pu pate in the capitula, making a cocoon out of the seed head material (Kashefi & Sobhian 1998). Larvae can destroy up to 100% of the seeds in a capitulum (Kashefi & Sobhian 1998). In the West ern United States, adult weevils emerge in late Sep and feed on plants until winter, when the adults overwinter in leaf litter and emerge in the following Jun (Jordan 1995). Larinus minutus was first released into the United States in 1991 with collections from Greece and Romania (Story 2002). Although 12 other natural enemy species were introduced into the Western United States and Canada to control spotted and diffuse knapweeds, only recently has adequate suppression of some populations been seen (Myers 2004; Smith 2004). Myers (2007) sug gested that knapweed populations did not signif icantly decline until the establishment of L. minutus. Populations of L. minutus have been es tablished in Washington, Wyoming, Oregon, Mon tana, Minnesota, Colorado, and Indiana (Lang et al. 1996; Story 2002). No natural enemies of spotted knapweed have been released in Arkansas until the inception of this study. However, we found Urophora quadrifasciata (Meigen) (Diptera: Tephritidae) established throughout the range of spotted knapweed in the state in a survey in 2006 for knapweed natural ene mies. This seedhead galling fly was introduced from Russia into Canada in 1980 and has since been re distributed or spread on its own to several states in the northeastern and northwestern United States (Story 2002). Duguma (2008) found that U. quadri fasciata reduced the number of seeds produced by spotted knapweed by 44% late in the season (Aug), at a time when plants are more environmentally stressed. However, the fly did not significantly re duce the number of seeds produced earlier in the season, a time when knapweed is most robust (Du guma 2008). Thus, it is likely that U. quadrifasciata alone will not significantly suppress knapweed pop ulations in Arkansas, or stop its spread further into the southern United States.