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The boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae), is an infamous pest of commercially cultivated cotton, Gossypium hirsutum L. (Malvales: Malvaceae). Once the most important agricultural pest in the United States, the boll weevil spurred an unprecedented mobilization of federal support and cooperation among stakeholders, culminating in the eventual eradication of the species from 98% of its invasive range in the United States. The US Boll Weevil Eradication Program, a joint effort of local, state, and federal governments and agencies, university and agency researchers, and the cotton producers themselves, is a prime example of a successful implementation of a community-wide integrated pest management (IPM). The program also dramatically reduced the use of insecticides in cotton production which led to further positive economic outcomes for producers and reduced the non-target impacts from those chemicals. Though the boll weevil has been mostly eradicated in the United States, the insect remains one of the most important and impactful cotton pests in Central and South America. In this review, we will revisit the agro-economic history of the boll weevil and examine the success of the US Boll Weevil Eradication Program. In doing so, we will learn how we can apply those lessons to boll weevil management abroad and community-wide management of other agricultural or invasive pests. Finally, we will conclude with a brief summary of the ongoing science that continues in service of eradication today.

Since the success of the U.S. Boll Weevil Eradication Program and widespread adoption of genetically modified crops, the cotton fleahopper, Pseudatomoscelis seriatus (Reuter), has reemerged as a significant cotton pest. Current management strategies for the pest are based primarily on foliar applications of insecticides. A line of cotton that produces modified Bt Cry51Aa2 protein was developed for Lygus spp., but the protein has also shown activity against the cotton fleahopper. Consequently, before this new Bt line can be released commercially, refuge requirements and other Insect Resistance Management (IRM) strategies mandated by the Environmental Protection Agency need to be established to prevent or delay development of resistance by cotton fleahopper to the new toxin. In response, we provide and discuss relevant information on the biology and ecology of the cotton fleahopper, including life history, host preference, dispersal, and population genetic structure, that may be useful for developing IRM strategies for the pest.

Reduced insecticide use in cotton, Gossypium hirsutum L., as a consequence of the Boll Weevil Eradication Program and the broad adoption of Bt cotton, have helped make the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), a consistent pest of cotton each year in the mid-south. Maize, Zea mays L., has been implicated as having a role in the season-long dynamics of tarnished plant bug infestations in cotton. To date, no published information exists describing the quality of maize as a host for tarnished plant bug. No-choice field studies indicated that adult tarnished plant bug females oviposited into maize leaves, tassels, and ears. Laboratory studies showed that first-instar tarnished plant bugs could successfully develop to the adult stage when fed maize silks at the R1 growth stage, tassels before (VT) and during (R1) pollen shed, and milk stage (R3) kernels from the tip and base of the ear. The proportion of nymphs surviving to the adult stage on these tissues was often similar to that of broccoli, Brassica oleracea L. Nymphs did not develop to adults when fed V5 or R1 maize leaves. However, survival of first instars to the adult stage was improved when nymphs fed on tassels with pollen for 6 d and then moved to silks or leaves. Another field study showed that tarnished plant bugs reproduced in maize mainly during the tassel (VE and VT) and the R1-R3 ear growth stages, and a single new generation was produced in maize during these stages. The highest population recorded during the study (24 June 2005) consisted mostly of nymphs and was estimated to be 29,600/ha (12,000/acre). These studies showed that maize is a suitable host for tarnished plant bug reproduction and development, and its production plays a significant role in the population dynamics of the tarnished plant bug in the mid-south.

The survival of overwintering boll weevil, Anthonomus grandis grandis (Boheman), adults on non-cotton hosts in the Lower Rio Grande Valley (LRGV) of Texas was examined from 2001 to 2006. The success of the Boll Weevil Eradication Program, which was re- introduced into the LRGV in 2005, depends on controlling overwintering boll weevil populations. Laboratory studies were conducted using boll weevil adults that were captured in pheromone traps from September through March. The number of adults captured per trap declined significantly in the field from fall to the beginning of spring (3.5-7.0-fold). The proportion of trapped males and females did not differ significantly. The mean weight of boll weevil adults captured in September was 13.3 mg, while those of captured adults from November to February were significantly lower and ranged from 6.7 to 7.8 mg. Our results show that boll weevil adults can feed on different plant pollens. The highest longevity occurred when adults were fed almond pollen or mixed pollens (72.6 days and 69.2 days, respectively) and the lowest when they fed on citrus pollen or a non-food source (9.7 days or 7.4 days, respectively). The highest adult survival occurred on almond and mixed pollens (88.0%-97. 6% after 1st feeding period (10 days), 78.0%-90.8% after 3rd feeding period (10 days), 55. 0%-83.6% after 5th feeding period (10 days), and 15.2%-32.4% after 10th feeding period (10 days)). The lowest adult survival occurred on citrus pollen (52.0%-56.0% after 1st feeding period (10 days), 13.3% after 3rd and 5th feeding periods (10 days), and 0 after 6th feeding period (10 days)). Pollen feeding is not a behavior restricted to adult boll weevils of a specific sex or physiological state. Understanding how boll weevil adults survive in the absence of cotton is important to ensure ultimate success of eradicating this pest in the subtropics.

In the Lower Rio Grande Valley (LRGV) of Texas, cotton regrows and produces fruit from undestroyed stalks throughout the winter, and in spring weevils from such locations become a serious threat. The success of the boll weevil eradication program, which was reintroduced in the LRGV in 2005, will be dependent on thorough stalk destruction following harvest. However, adverse weather conditions and conservation tillage often impede immediate and complete stalk destruction using typical tool implements, and alternative stalk control methods are needed. This study provides an examination of the efficacy for cotton stalk destruction of different herbicides (thifensulfuron-methyl + tribenuron-methyl, dicamba-diolamine, 2,4-D-dimethylammonium, flumioxazin, 2,4- DB-dimethylammonium and carfentrazone-ethyl) and their rates, spray volumes and application timings on shredded or standing cotton stalks after stripper or picker harvest. None of the tested herbicides, except 2,4- D-dimethylammonium, stopped post-harvest cotton regrowth and fruiting. 2,4-D-dimethylammonium sprayed once (0 or 7days) after cotton was harvested at 1lb AE acre −1 (1.12kg ha −1 ), in a spray volume of 10gal water acre −1 (93.5L ha −1 )w ith 5mL L −1 surfactant, was highly effective in stalk destruction (72-90%). The best results were achieved when the herbicide was applied immediately after the cotton was shredded, followed by standing stripper-harvested and standing picker-harvested cotton. 2,4-D-dimethylammonium applied twice, 0 and 14 (or 21) days after cotton harvest, was 100% effective in killing stalks, regardless of whether they were shredded or standing, or whether harvest was by stripper or picker. These findings showed that 2,4-D-dimethylammonium cotton stalk destruction eliminated food and reproductive opportunities for managing overwintering boll weevils (Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae)). Published in 2007 by John Wiley & Sons, Ltd.

Several boll weevils, Anthonomus grandis Boheman, were captured in pheromone traps in 2004 near Tlahualilo, Durango, Mexico, an area where none had been reported for ≈10 yr. It is possible that they were from an endemic population normally too low in numbers to be detected but that increased in response to more favorable rainfall conditions in 2004. Alternatively, they may represent an influx of migrants or the immediate descendents of migrants. To identify the most likely origin of the boll weevils captured in this area, we characterized microsatellite variation of the Tlahualilo weevils and compared it with the variation from three other populations in northern Mexico and from one in southern Texas. Measures of gene flow and individual assignment tests suggest that the boll weevils captured near Tlahualilo were primarily from an endemic low-level population, but that this area also is receiving immigrants from a cotton growing region ≈200 km to the north, near Rosales, Chihuahua, which is currently under a boll weevil eradication program. Similarly, Rosales is receiving immigrants from Tlahualilo. This study shows that microsatellite markers and population assignment techniques will be practical tools for determining the most likely origins of boll weevils reintroduced to eradication zones in the United States and Mexico. Population assignment strategies based on genetic markers hold promise for replacing conventional, but spatially constrained, mark-recapture studies of insect dispersal. This relatively new and powerful analytical approach is widely used in conservation genetics and fisheries studies, but has been underused by entomologists.

Cotton is the most important fiber crop in the world, and current U.S. lint production accounts for nearly one quarter of the world supply. The unique role of cotton in world and American history is profound. Primitive cottons have been used in Africa, Asia, and the Americas for millennia. Domestic and international demand for cotton fiber contributed greatly to the westward expansion of the United States, the American Civil War, and the industrial revolution (81). The land area devoted to cotton production in the United States peaked in 1926 with approximately 18 million hectares (Fig. 1). The advent of mechanized farming equipment and the availability of effective, relatively low-cost fertilizers, pesticides, and improved cotton cultivars after World War II allowed the production of significantly greater yields per unit of land area, and hectarage declined. U.S. production of cotton lint in the past 5 years has varied from 3.0 × 10 to 4.4 × 10 kg produced on about 5 million hectares (147). Additionally, cotton seed is a valuable source of vegetable oil and protein used in animal feed, with production of 4.9 × 10 to 5.9 × 10 kg of cotton seed annually. Since World War II, cotton cultivation was increasingly dependent on inputs of chemical pesticides for weed and insect control. Historically, the cotton boll weevil, Anthonomus grandis Boheman, was the most costly pest of cotton in the United States. The combination of crop loss due to this insect directly and the expense for insecticides that was incurred by cotton growers attempting to control it amounted to several billion dollars annually until recently (130). The successful establishment of the Boll Weevil Eradication Program coordinated by the U.S. Department of Agriculture in many states in the eastern half of the country has resulted in a reduction in insecticide usage, improved profitability for growers, and has led to a resurgence of cotton production in the Southeast (37). In addition, the current widespread use of transgenic cotton cultivars with resistance to herbicides and/or insects also has greatly reduced the need for inputs of pesticides. Currently, 71% of cotton grown in the United States is herbicide resistant, resistant to lepidopteran insects, or has resistance to both (3). Reductions in pest pressure from weeds and insects as a result of the deployment of transgenic resistance and the boll weevil eradication program have

Invasions of boll weevil ( Anthonomus grandis ) into the United States and sea lamprey ( Petromyzon marinus ) into the Great Lakes were similar in many ways. Important species (American cotton, Gossypium hirsutum , and lake trout, Salvelinus namaycush ) and the industries they supported were negatively affected. Initial control efforts were unsuccessful until pesticides and application technologies were developed. For boll weevils, controls relying on pesticides evolved into an integrated program that included recommended farming practices and poisoned baits. However, the discovery of a boll weevil sex pheromone in 1964 allowed adoption of an ongoing program of eradication. Despite opposition over concept and cost, insecticides, pheromone traps, poisoned baits, and approved farming practices were used to eradicate boll weevils from Virginia, North Carolina, South Carolina, Georgia, Florida, and Alabama by 1999. Using the working back approach along the path of the original invasion, eradication was nearly completed by 2002 in Mississippi and eradication programs were underway in Arkansas, Tennessee, Oklahoma, Louisiana, and parts of Texas. Insecticide use for cotton production decreased 50 to 90%, and cotton yields and farm income increased an average of 78 kg/ha and $190 U.S./ha in areas where boll weevils were eradicated. For sea lampreys, integrated management uses lampricides, barriers to migration, trapping, and release of sterilized males. Although sea lamprey eradication is not currently feasible, recent research on larval and sex pheromones might provide the tools to make it possible. A successful eradication program for sea lampreys starting in Lake Superior and expanding to the lower Great Lakes would ultimately provide huge ecological and economic benefits by eliminating lampricide applications, removing barriers that block teleost fishes, and facilitating the recovery of lake trout. Should the opportunity arise, the concept of sea lamprey eradication should not be rejected out of hand. The successful boll weevil eradication program shows that sea lamprey eradication might be achievable.

The body of King Cotton lies amouldering in the grave, but his soul has been metempsychosized. Cotton dominated the agriculture of the South in 1929, the peak year, when 1,719,165 farmers grew 42,579,522 acres of the crop. Few grew more than 15 acres, or produced more than one-third of a bale per acre. They grew it in small patches with backbreaking hand labor, especially for the tasks of chopping and picking. In 1997 only 24,860 farmers in the South grew cotton, but they grew 11,799,225 acres. They had consolidated the erstwhile patches into large open fields. They averaged 425 acres of cotton, and produced better than a bale per acre. Agrichemicals and machines had replaced hand labor, and one-fifth of the crop was irrigated. The boll weevil eradication program, which has spread outward from northeastern North Carolina, has decimated production costs, and the price had been favorable. Inadequate gin capacity has forced farmers to shift from field wagons to modules, and a new cotton landscape has been created in the South.

An adaptive regression model is employed for estimating pre- and post-boll weevil eradication cotton-acreage response. Results indicate cotton acreage becoming more inelastic to own- and cross-price changes. As a result of this shift in acreage response and yield increases from eradication, net producer benefits on average are $88.73 per acre.

The effect of early-season flower bud damage on yield, quality, and maturity of cotton, Gossypium hirsutum L., was determined at Florence and Blackville, SC, from 1989 to 1994. From 1989 to 1991, yields from insecticide-treated plots for Heliothis virescens (F.) during June were compared with plots left untreated during June. In all cases from 1989 to 1991, no significant differences in yield were observed between treated and untreated plots. From 1992 to 1994, H. virescens damage was simulated by hand-removal of flower buds. In 1992, no significant differences were observed in yield, maturity, or lint quality following removals as high as 100% for 4 consecutive weeks. In 1993, a 1-wk delay in maturity was observed in 'DES 119' and 'Deltapine 90' at both locations following removals of 100% for 3 and 4 wk, and in 1994 at Blackville following removals of 100% for 3 wk. From 1992 to 1994, there were no significant yield effects following any flower bud removal level or duration, but in 1993 at Blackville, there were significant removal X planting date and removal X planting date X cultivar interactions. In this instance, DES 119 planted late (28 May) and grown under irrigated and dryland conditions experienced yield reductions of 30-45% after 100% removal for 3 or 4 wk that extended into mid-July. No other significant interactions with removal occurred, and no differences in lint quality were observed. Our data indicate that cotton compensates adequately for flower bud loss in June in South Carolina, and that insecticides for H. virescens seldom are needed early in the season. Opportunities to ameliorate traditional insecticide approaches for cotton insect management are discussed by considering our data in conjunction with the expansion of the Boll Weevil Eradication Program and the deployment of cotton cultivars that contain genes for expression of the delta-endotoxin of Bacillus thuringiensis in other areas of the Cotton Belt.

Concerns have been expressed about the potential insecticide contamination of regional water resources from a boll weevil eradication program in Oklahoma. A mathematical model and geographic information system techniques were utilized to evaluate the potential of insecticide leaching and runoff from a major proposed program area in the state. Different but equally likely weather patterns were generated, and potential insecticide losses associated with each pattern were predicted. Soil types and their locations within cotton areas were identified, and potential chemical losses from each soil were delineated. Model simulations indicated that azinphos-methyl and diflubenzuron could leach from some porous soils and that all insecticides suggested for use in the program could be lost to runoff. The predicted chemical movements with runoff were significantly higher on irrigated land than from non-irrigated land. Malathion demonstrated no leaching and low potential of runoff losses among the insecticides evaluated.

Although the economic benefits of boll weevil eradication programs have been theoretically and empirically documented, a history of failed initial referendums can be attributed to concerns about relative program costs and benefits, changes in the pest management property rights of producers, and the lack of landowner cooperation with producers. Because little is known about the role of knowledge, opinion, and landowners in the success or failure of any cooperative pest management program, problems arise when attempting to design and promote a boll weevil eradication program. This study examined the factors that played a role in the defeat of the March 1995 Louisiana boll weevil eradication referendum and characterizes the actions that could be taken to successfully promote coordinated pest management programs like boll weevil eradication. Accurate knowledge of past program successes was important to developing support for boll weevil eradication, but knowledge of program specifics led to opposition, particularly in production regions with relatively low boll weevil infestations. These results suggest that program development, education, and promotion need to address regional differences in pest control demand. Although landowners were not different from producers in terms of their willingness to support the boll weevil eradication program, they appear more open to targeted education programs that increase their level of knowledge concerning the boll weevil eradication program and the concept of coordinated pest management. Overall, this study suggests that the development of a clientele knowledge base is important to the successful implementation of coordinated pest management, but that this task may require long-term, broadly targeted educational efforts.

The plant growth regulator ethephon, Prep ([2-chloroethyl] phosphonic acid), and the desiccant arsenic acid, Desiccant L-10, were evaluated for their effects on late-season squares, green bolls, and yield of the cotton, Gossypium hirsutum , cultivars, ‘Lankart 511’, ‘Lankart Sel. 611’, and ‘TAMCOT CAB-CS’, in a dryland cotton production system in 1990 and 1991. Damage to squares and bolls by the boll weevil, Anthonomus grandis grandis Boheman, was evaluated in 1991. All cotton cultivars treated with Prep (1.26 kg(AI)/ha) and Desiccant L-10 (2.63 1(AI)/ha) in September had reduced numbers of squares in October and November compared with untreated cotton. Plots were harvested in early December after a killing freeze. Both Prep and Desiccant L-10 reduced the number of green bolls and cotton squares damaged by boll weevils in all cultivars in October. Yield was not significantly reduced by either chemical in 1990 or in 1991. The late-maturing ‘Lankart Sel. 611’ had lower yields across treatments in 1990 and in 1991 than the intermediate-maturing ‘Lankart 511’ and the early-maturing ‘TAMCOT CAB-CS’. A single late-season application of a harvest aid chemical for reduction of fall food may help control boll weevils and reduce the need for fall insecticide applications in dryland cotton. Relevance of this research to the Texas Boll Weevil Eradication Program is discussed.

The boll weevil, Anthonomus grandis (Boheman), has been a major insect pest of cotton production in the US, accounting for yield losses and control costs on the order of several billion US dollars since the introduction of the pest in 1892. Boll weevil eradication programs have eliminated reproducing populations in nearly 94%, and progressed toward eradication within the remaining 6%, of cotton production areas. However, the ability of weevils to disperse and reinfest eradicated zones threatens to undermine the previous investment toward eradication of this pest. In this study, the HYSPLIT atmospheric dispersion model was used to simulate daily wind-aided dispersal of weevils from the Lower Rio Grande Valley (LRGV) of southern Texas and northeastern Mexico. Simulated weevil dispersal was compared with weekly capture of weevils in pheromone traps along highway trap lines between the LRGV and the South Texas / Winter Garden zone of the Texas Boll Weevil Eradication Program. A logistic regression model was fit to the probability of capturing at least one weevil in individual pheromone traps relative to specific values of simulated weevil dispersal, which resulted in 60.4% concordance, 21.3% discordance, and 18.3% ties in estimating captures and non-captures. During the first full year of active eradication with widespread insecticide applications in 2006, the dispersal model accurately estimated 71.8%, erroneously estimated 12.5%, and tied 15.7% of capture and non-capture events. Model simulations provide a temporal risk assessment over large areas of weevil reinfestation resulting from dispersal by prevailing winds. Eradication program managers can use the model risk assessment information to effectively schedule and target enhanced trapping, crop scouting, and insecticide applications.

The success of the Boll Weevil Eradication (BWE) Program is believed to be one factor underlying the recent increase in cotton acreage in the Southeast. We find weak evidence that the initial, eradication phase of the BWE program decreases cotton acreage, and strong evidence that the second, maintenance phase of the program increases acreage. The full benefits associated with a BWE program may not become apparent until acreage adjustments occur, four to five years after program initiation. Our results indicate that for a representative sample county neglecting acreage effects may lead to underestimation of BWE program net benefits by 9 percent-12 percent.

The success of the Boll Weevil Eradication (BWE) Program is believed to be one factor underlying the recent increase in cotton acreage in the Southeast. We find weak evidence that the initial, eradication phase of the BWE program decreases cotton acreage, and strong evidence that the second, maintenance phase of the program increases acreage. The full benefits associated with a BWE program may not become apparent until acreage adjustments occur, four to five years after program initiation. Our results indicate that for a representative sample county neglecting acreage effects may lead to underestimation of BWE program net benefits by 9 percent-12 percent.

Five-year, 0-1 mixed integer programming models of two representative Alabama farms were developed for analyzing the effects of the Boll Weevil Eradication (BWE) program on farm program participation and crop-mix decisions by Alabama cotton farmers. In previous research the BWE program was found to increase yields by approximately 100 pounds per acre in Georgia and southern Alabama where the program has been in effect for several years. In this study, these increased yields are shown to be an important factor contributing to the expanded cotton acreage in southern Alabama. For northern Alabama, gains to producers are also possible, but not to the extent realized in the southern part of the state.

The economic viability of the Boll Weevil Eradication Program in Alabama, Florida, and Georgia is assessed based on a five-year survey of producers. Results indicate the program increases yield 100 pounds per acre. This implies a 19 percent internal rate of return for producers over a ten-year period.

This paper is a historical and philosphical reconstruction of how U.S. entomologists attempted to mitigate the depradations of the boll weevil on cotton, the world's most important natural fiber. The boll weevil caused severe losses in the U.S. after 1892. Early control methods were based on altering the cultural practices of cotton growers. The discovery in 1917 that calcium arsenate was an effective insecticide for boll weevils eventually allowed some farmers to rely on chemical control. Development of synthetic, organic insecticides allowed many U.S. growers after 1945 to rely heavily on insecticides for boll weevils. By the 1960s, resistance of boll weevils to insecticides, induction of secondary pest outbreaks, and environmental health hazards threatened cotton production practices based on insecticides. U.S. entomologists devised two new strategies to rescue cotton production from its insecticide crisis: integrated pest management (IPM) and total population management (TPM). Eradication of key insect pests such as boll weevils was envisaged by TPM entomologists with adequate technology. E.F. Knipling, the USDA entomologist who designed TPM, gave 1968 as a target for possible boll weevil eradication. The pilot boll weevil eradication experiment (PBWEE) was conducted in 1971–1973. IPM entomologists argued the futility of attempting to eradicate the boll weevil from the U.S.A., but TPM adherents argued for a second test, which was held in Virginia, North Carolina and South Carolina (1978–1980). A new controversy erupted over how to interpret the fact that a few boll weevils were found at the end of the second test. IPM and TPM entomologists were once again pitted against one another on three major issues: defining eradication; explaining secondary pest behavior; and drawing conclusions about the wisdom of a national boll weevil eradication program. Currently, entomologists have reached a stalemate over boll weevil eradication in the U.S. Some entomologists are attempting to synthesize opposing views in the hope of reaching a professional consensus on appropriate boll weevil suppression methods. Significant distinctions separate IPM and TPM and will make it difficult to achieve an agreement. Budgetary problems in the U.S.A. argue for a management rather than eradication stance against boll weevils. The split in the U.S. entomological profession could have adverse effects on efforts to develop insect-control science outside of the U.S.

Throughout the southern states and at the federal level, much attention is being focused on the appropriate strategy for controlling cotton insect pests, particularly the boll weevil. This paper presents estimated economic impacts to farmers, regions and consumers of implementing three alternative boll weevil control strategies. One strategy evaluated is a proposed boll weevil eradication program which involves integrating many controls including insecticides, reproduction-diapause control by early season stalk destruction, pheromone-baited traps, trap crops, early season control with insecticide, and massive releases of sterile boll weevils. The plan is to eradicate the boll weevil in the U.S., and then indefinitely maintain a barrier at the U.S.-Mexico border to prevent future weevil immigration to the U.S.

In field cage and isolated field tests the response of virgin female boll weevils, Anthonomus grandis Boheman, to male-baited traps was from 2 to 9 times greater than that of mated females. Females that had mated as long as 1 wk prior to release were still not as responsive as were virgins. The interval after the last mating may be important in determining whether or not a mated female will remate. Response of mated females is also influenced by male density. The fact that some mated native females will respond to males a second time should be beneficial to a boll weevil eradication program. In field cage tests the response of sterile female boll weevils to male-baited traps was approximately the same as that of fertile females. If eradication of the boll weevil is attempted, the release of sterile females along with the sterile males may contribute to premature sperm depletion of the sterile males, unless an effective pheromone trapping system is devised to remove these females from the field after release.

The grandlure-baited boll weevil trap is an essential component of most, if not all, boll weevil control programs. While there are other minor uses of grandlure, the major use is as an attractant for the boll weevil trap. The Southeastern Boll Weevil Eradication Program uses the grandlure-baited boll weevil trap to determine areawide distribution of boll weevils, field-by-field presence of boll weevils, where and when to apply insecticide treatments and suppress very low populations of boll weevils.