Plum curculio (PC), Conotrachelus nenuphar (Herbst) (Coleoptera: Curculionidae), is a key pest of Southeastern US peaches. To facilitate the development of spatiotemporally targeted management approaches and improve the deployment and design of monitoring traps, we studied PC's vertical distribution within peach orchards and whether their dispersal patterns resulted in an orchard edge effect. Non-baited Whalon-modified Tedder's traps (black pyramid traps; ∼120 cm in height) deployed at 3 heights-0 (low), 120 (medium), and 240 (high) cm above the ground-revealed that PC were captured at all heights but predominantly in the low traps. Additionally, correlations among PC captures at different heights were often nonsignificant. Although we documented the presence of PC's edge effects in Georgia peaches for the first time, the occurrence of these effects was inconsistent across 2 yr, failing to regularly appear early in the season when PC entered the orchard from overwintering sites and late in the season when they departed to seek overwintering sites. Overall, our findings suggest that relying solely on ground-deployed pyramid traps for PC monitoring may not accurately reflect overall PC abundance in the field. Unlike in Northeastern apples, where PC consistently exhibits an edge effect, targeted management programs that focus insecticide applications on PC in perimeter tree rows rather than the entire orchard are not currently recommended for Southeastern peach production systems.

The pecan weevil, Curculio caryae (Horn) (Coleoptera: Curculionidae), is a direct pest of pecan nuts often causing economic injury. Larvae feed and develop within the pecan nut, mature fourth instars emerge from nuts during autumn, drop to the orchard floor and complete development underground. However, a proportion of pecan weevil larvae remain in nuts at harvest. We tested electron beam irradiation of pecan weevil larvae as a potential phytosanitary treatment against infested nuts being shipped to production regions free of pecan weevil. Irradiation doses of 0, 150, 400, 750, and 1,000 Gy were assayed against pecan weevil using different larval exposure methods (bare larvae [bare], larvae in microfuge tubes [tube], and larvae in microfuge tubes placed into empty pecan shells [nut]). After treatment application, larvae were held singly in Petri dishes at 15 °C and examined for 60 d to determine mortality. Results revealed that larval mortality increased with days after treatment for each irradiation dose, including 0 Gy, for the 3 exposure methods. Mortality was generally lower for larvae in the tube and nut at 400, 750, and 1,000 Gy than for bare larvae. Overall mortality was lower for lower irradiation doses but higher for higher doses, and over time no larvae survived 1,000 Gy. These results strongly suggest that irradiation is an effective method to control in-shell pecan weevil larvae.

In perennial agroecosystems, pest management outcomes are influenced by herbivore ecology and farming practices that shape arthropod activity. Yet, across many systems, information on taxonomic composition, spatiotemporal dynamics, and sensitivity of herbivore groups to crop management is sparse. In perennial tree crops, Auchenorrhyncha (Hemiptera) are abundant herbivores, notable for causing feeding damage and transmitting plant pathogens. Here, to strengthen the ecological understanding of Auchenorrhyncha activity in managed tree systems, we tracked the seasonal abundance and within-canopy distribution of Auchenorrhyncha in a mature pecan (Carya illinoinensis) orchard over two seasons and evaluated how these patterns interact with common canopy management interventions: hedge pruning and calendar-based pesticide applications of insecticide and fungicide. We collected 5882 Auchenorrhyncha, representing seven families. The assemblage was dominated by Cicadellidae, with over 95

Phony peach disease (PPD), caused by Xylella fastidiosa subsp. multiplex (Xfm), poses a significant threat to commercial peach orchards in Georgia. Early and accurate detection is essential for effective disease management, yet visual assessment remains the primary approach for diagnosing PPD symptoms due to the high cost and logistical challenges of qPCR-based detection of Xfm. We evaluated the accuracy of visual PPD assessment and examined the factors influencing rater performance, symptom reliability, and optimal survey deployment strategies with classification and regression trees/random forest analyses and simulations. Internode length was the most reliable symptom for PPD identification in two peach cultivars, consistently outperforming other physical traits, such as canopy flatness and shape. Primer pair C06Xf-bamA had the greatest relative sensitivity, making it the preferred choice for qPCR confirmation. Principal component analysis suggested that rater experience significantly improved agreement with qPCR results, and repeated assessments of the same orchards further enhanced consistency for raters. Simulation results suggested that deploying two experienced raters may provide the highest detection diagnostic accuracy for survey purposes, particularly when qPCR-based pathogen detection is unavailable. Finally, PPD-affected trees, through PCR verification and visual identification, exhibited higher mortality rates than Xfm-negative trees, reinforcing the need for early detection and removal to limit disease spread. These findings underscore the importance of strategic rater deployment, targeted symptom selection, and integrating molecular diagnostics when feasible.

The ambrosia beetles Xylosandrus crassiusculus (Motschulsky) and Xylosandrus germanus (Blandford) (Coleoptera: Curculionidae) are major pests in fruit, nut, and ornamental tree nurseries. Adult females tunnel into stressed trees, creating galleries in the sapwood and heartwood to cultivate their nutritional fungal mutualists, which are associated with branch dieback and tree death. The current management approach relies on trunk applications of permethrin and bifenthrin to decrease infestation risk in the United States. However, the efficacy of other insecticides has not been thoroughly evaluated. Fourteen trials were conducted in Virginia, South and North Carolina, Tennessee, and Georgia to evaluate the efficacy of various synthetic and biological or microbial insecticides as potential management tools in tree fruits, pecans, and ornamentals. Of the 24 active ingredients tested, only 5 pyrethroids (permethrin, bifenthrin, lambda-cyhalothrin, deltamethrin, and cypermethrin) reduced the numbers of entry holes in ethanol-infused bolts. The effectiveness of permethrin and bifenthrin against ambrosia beetles was consistent and superior to that of lambda-cyhalothrin, deltamethrin, and cypermethrin. Dinotefuran significantly reduced ambrosia beetle attacks in one trial. Spinosad, sulfoxaflor + spinetoram, chlorantraniliprole, cyantraniliprole, cyclaniliprole, tetraniliprole, tolfenpyrad, indoxacarb, isocycloseram, carbaryl, Burkholderia spp., Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae), Chromobacterium subtsugae PRAA4-1T (Neisseriales: Neisseriaceae), and Paecilomyces fumosoroseus (Wize) Kepler, B. Shrestha & Spatafora (Hypocreales: Cordycipitaceae) did not reduce beetle attacks. Thus, among insecticidal and biological products, only pyrethroid insecticides protect vulnerable trees by reducing entry holes from Xylosandrus spp. and remain a reliable tool for preventing their infestation in tree fruits, pecans, and ornamentals.

The invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is a significant insect pest in agricultural systems, including pecan orchards. Natural enemies, such as stink bug egg parasitoids, may help control H. halys outbreaks in pecan. The addition of a floral resources, such as crimson clover, which attract and support parasitoids, may further increase rates of parasitism as well as parasitoid abundance. We tested whether parasitoid abundance and attack on H. halys egg masses differed in tree canopies or on the ground next to trees in pecan orchards with and without crimson clover. We monitored presence of parasitism with H. halys sentinel egg masses and parasitoid abundance with yellow sticky cards. Overall, parasitism of sentinel egg masses was greater in orchards with crimson clover than without and greater at ground level compared to the canopy. Parasitoid abundance in orchards was similar whether crimson clover was present or not. However, we detected more parasitoids at ground level, a pattern driven by high numbers of Telenomus podisi (Ashmead). Despite similar parasitoid abundance, increased parasitism of sentinel egg masses suggests that crimson clover improves biological control of H. halys in pecan orchards. Importantly, planting crimson clover in pecan orchards is a simple, sustainable approach for growers to better control H. halys.

Invasive species can significantly alter ecosystems, often through competitive dominance and indirect ecological effects. The harlequin ladybird (Harmonia axyridis) has become a widespread invasive species that, after a period without natural enemies, became parasitized by different organisms in the invaded range, including the microfungus Hesperomyces harmoniae. These parasite-host interactions remain understudied. Here, we investigated how temperature and humidity influence parasitism of He. harmoniae on Ha. axyridis using controlled laboratory experiments. We tested different environmental conditions: low versus high relative humidity and low versus high temperature. We assessed parasite prevalence (proportion of infected ladybirds), rate of development (time to maturity of fungal thalli) and parasite load (average number of thalli per host). High humidity increased both parasite prevalence and rate of development. High temperature had a slight negative effect on both measures, whereas low humidity and low temperature had a strong negative effect. Hesperomyces harmoniae thrives best under moderately warm and humid conditions and its prevalence may be constrained in drier or cooler environments. Understanding the environmental factors influencing He. harmoniae dynamics provides insights into the role of abiotic conditions in shaping parasite-host interactions. Our findings have implications for the population ecology of Ha. axyridis in different climatic regions.

Advances in molecular ecology can overcome many challenges in understanding host-parasitoid interactions. Genetic characterization of the key-players in systems helps to confirm species and identify trophic linkages essential for ecological service delivery by biological control agents; however, relatively few agroecosystems have been explored using this approach. Pecan production consists of a large tree perennial system containing an assortment of seasonal pests and natural enemies. As a first step to characterizing host-parasitoid associations in pecan food webs, we focus on aphid species and their parasitoids. Based on DNA barcoding of field-collected and reared specimens, we confirmed the presence of 3 species of aphid, one family of primary parasitoids, and 5 species of hyperparasitoids. By applying metabarcoding to field-collected aphid mummies, we were able to identify multiple species within each aphid mummy to unravel a complex food web of 3 aphids, 2 primary parasitoids, and upward of 8 hyperparasitoid species. The results of this study demonstrate that multiple hyperparasitoid species attack a single primary parasitoid of pecan aphids, which may have negative consequences for successful aphid biological control. Although further research is needed on a broader spatial scale, our results suggest multiple species exist in this system and may suggest a complex set of interactions between parasitoids, hyperparasitoids, and the 3 aphid species. This was the first time that many of these species have been characterized and demonstrates the application of novel approaches to analyze the aphid-parasitoid food webs in pecans and other tree crop systems.

The brown marmorated stink bug, Halyomorpha halys (St & aring;l) (Hemiptera: Pentatomidae), is an invasive, polyphagous pest known to disperse between non-crop host plants and crops searching for food. Sugarberry (Celtis laevigata Willdenow; Cannabaceae) is commonly found in woodland habitats in the southeastern USA and may serve as a non-crop host for H. halys. Therefore, the main objective of this two-year study was to determine if 1) sugarberry serves as a host tree and 2) whether natural enemies attack H. halys sentinel egg masses in the tree canopy. We monitored H. halys in sugarberry trees in woodlands bordering field crops in Prattville, Alabama during 2022 and similarly for orchard crops in Byron, Georgia during 2023. Each year pheromone-baited stink bug traps were deployed in the canopy of trees to capture H. halys. We evaluated parasitism and predation of H. halys by placing sentinel egg masses in tree canopies. H. halys males and females and 2nd through 5th instars were captured in tree traps over the season for each location. Trissolcus euschisti (Ashmead) (Hymenoptera: Scelionidae) was the only parasitoid species that emerged from H. halys eggs. Chewing and stylet sucking were the primary types of predation on sentinel egg masses. We conclude that sugarberry is a reproductive host for H. halys, and native natural enemies provide biological control services of H. halys eggs on this host.

Leptoglossus (Hemiptera: Coreidae) are a diverse genus of phytophagous insects. Literature regarding Leptoglossus has increased as species are identified as emerging agricultural pests or reported outside of their native range. Within Leptoglossus, five species dominate the literature and are known pests and vectors of plant pathogenic microbes in several major crops. Despite the increasing profile of Leptoglossus, current monitoring and management methods rely primarily on visual inspection, and semiochemical tools have yet to be developed. This Perspective identifies and discusses gaps in the Leptoglossus literature as well as areas of research needed for the development of effective tools for monitoring insect populations and enabling informed pest-management practices.

Plum curculio, Conotrachelus nenuphar (Herbst) (Coleoptera: Curculionidae), is a key pest in Southeastern peach production by infesting fruit and decreasing yield. In Northeastern apples, plum curculio was found to have an "edge effect," where more plum curculio are present next to a forested border than in the center of an orchard, and their propensity to fly or walk depended on air temperature. We conducted field studies over 3 seasons (2019-2021) to investigate whether plum curculio in small Southeastern peach plots exhibits the edge effect and to determine its primary mode of movement (flying or walking). Our results revealed that plum curculio did not exhibit the edge effect in Southeastern peaches. Thus, unlike Northeastern apples where plum curculio exhibits the edge effect, the reduced-input application program where insecticide sprays mainly target a few perimeter-row trees instead of the whole orchard for plum curculio management is not recommended for Southeastern peaches. Additionally, we observed that plum curculio in Southeastern peaches did not exhibit a primary mode of movement, and in most of the sampling weeks, the numbers of flying and walking plum curculio were not significantly correlated in the field. These results emphasize that using plum curculio sampling tools that only capture flying or walking plum curculio is not ideal for monitoring plum curculio activity in the Southeast. Overall, our findings indicate that plum curculio in Southeastern small peach plots and Northeastern apples does not exhibit the same behavior (i.e., edge effect and propensity to fly or walk).

The pecan leafroll mite, Aceria caryae (Keifer) (Acari: Eriophyidae), is a small cigar-shaped mite, normally measuring 0.1–0.2 mm long. The mite uses a ventral sucker located on its caudal end for attachment to the host plant while it feeds using piercing mouthparts that are short and thus limiting feeding to the epidermal cells (Grasswitz 2012, USDA Forest Service Proceedings, New Mexico). There are nearly 2,000 species of eriophyid mites (Davis and Beddes 2011, Utah Pests Fact Sheet, ENT-149-11) and most are host specific, which makes some species ideal for biological control of weed species (Skoracka et al. 2010, In E.D. Uekermann [ed.], Eriphyoid Mites: Progress and Prognoses, Springer, NY). Feeding symptoms vary, but can include galls, stunting, blisters, leaf curl, rust, silvering, fruit russeting, witches' broom, stunting and deformities of seedlings.On pecan, Carya illinoinensis (Wangenheim) Koch, the adult pecan leafroll mite feeds on the lateral edge of the adaxial surface of young, expanding leaflets during the early spring (Davis and Beddes 2011). Feeding along the leaf edge causes cells on the adaxial surface to grow slower than those cells on the abaxial side, hence forming a gall-like deformation along the lateral leaf margin and causing the leaf edge to curl up in a tight roll. Although this distortion to the leaf occasionally turns brown, defoliation does not occur. For many host plant species, damage is generally cosmetic and not a significant problem, allowing control by pruning infested branches or removing damaged leaves (Grasswitz 2012). However, the large size of many infested pecan trees precludes this as an option.During migration between plant tissues, the eriophyid mites are more exposed and vulnerable to natural enemies such as predaceous mite species (Stigmaeidae and Phytoseiidae), spider mite destroyer lady beetle, Stethorus punctum (LeConte) (Coleoptera: Coccinellidae), and predaceous midge larvae (Diptera: Cecidomyiidae) (Skoracka et al. 2010). In addition, plant defense mechanisms such as dense setae on leaves or buds, thicker plant cell walls, or secondary plant compounds may protect against mites feeding on the host plant (Skoracka et al. 2010). The objective of the study was to assess whether foliar feeding by the pecan leafroll mite negatively affects leaf area and leaf chlorophyll content and gas exchange parameters.The experiment was conducted from July to September 2022 in an approximately 25-yr-old pecan orchard of cv. Desirable near Fort Valley, GA (32.55559 N, −83.82753 W). Three trees were randomly selected for data collection. Compound leaves, with or without pecan leafroll mite injury, were selected for examination of gas exchange parameters and leaf area. Leaf readings were taken from attached leaves with and without leafroll injury by using a LI-6800 portable meter (LI-COR, Lincoln, NE) and included net carbon assimilation rate (A), transpiration rate (E), and stomatal conductance to water vapor (gsw). These measurements were taken between 9:00 a.m. and 12 p.m. under field conditions at 1,860 µmol·m−2·s−1 photosynthetic photon flux density and ambient atmospheric CO2 levels (385 ± 23 µmol·mol−1). Gas exchange treatment effects were analyzed using full factorial analysis of variance (ANOVA) using PROC GLM procedure followed by a multiple comparison of means using Tukey's protected honestly significant difference at P = 0.05 (SAS Institute Inc., Cary, NC). Leaf chlorophyll content was determined on attached leaves by using a portable SPAD-502Plus meter (Konica Minolta, Tokyo, Japan) on three leaflets for each of three compound leaves with and without pecan leafroll mite injury. Additional compound leaves with and without pecan leafroll mite injury were collected and taken to the lab for leaf area analysis. On three trees, three compound leaves with pecan leafroll mite injury were collected from three terminals having compound leaves with pecan leafroll mite injury (n = 27 leaves). On the same three trees, compound leaves without pecan leafroll mite injury were similarly collected from terminals without pecan leafroll mite injury (n = 27 leaves). The total number of leaflets per compound leaf was recorded because the number of leaflets per compound leaf varies. Because all leaflets on a compound leaf may not exhibit mite injury, the number of leaflets with pecan leafroll mite damage on those compound leaves with pecan leafroll mite injury was documented. The area of each leaflet on all compound leaves was measured using image analysis software (Image-Pro Premier v.9.3.1, Media Cybernetics, Rockville, MD). Leaflet area for compound leaves with and without pecan leafroll mite injury was analyzed using a one-way ANOVA (JMP 1989–2021). On compound leaves with pecan leafroll mite injury, leaflets with and without injury were analyzed using one-way ANOVA (JMP 1989–2021).SPAD readings are a nondestructive measure of leaf chlorophyll concentrations in which the value is proportional to amount of chlorophyll in the leaf. In this study, leaves with pecan leafroll mite damage had higher SPAD values, but no significant differences in chlorophyll content were observed between healthy leaflets and leaflets with mite damage (P = 0.2146). Differences in net carbon A were not observed between treatments among the three sampling periods. However, significance was observed among dates and treatments for E and gsw (Table 1). Because gsw is a measure of the degree of stomatal opening, it can be used as an indicator of plant water status. A reduced gsw on leaves with pecan leafroll mite damage may indicate water stress and hence lower E, or water movement through the plant as the stomates close to preserve water.Upon visual inspection, pecan leaf roll mite damage on individual leaflets appears to decrease leaflet area, which could affect net photosynthesis and in turn nut development, quality, and yield (Lombardini 2006, HortScience 41: 1469–1473). A comparison of mean leaflet area from compound leaves with pecan leafroll mite injury compared with compound leaves without this injury did not reveal a significant difference in leaflet area for 28 July (F = 12.31; df = 1, 5; P = 0.0725), 29 August (F = 11.69; df = 1, 5; P = 0.0759), or 27 September (F = 1.47; df = 1, 5; P = 0.3487). However, on compound leaves with mite injury, those leaflets with mite injury had lower leaflet area than those leaflets without mite injury and the difference was significant on 28 July (F = 123.68; df = 1, 5; P = 0.0080) and 27 September (F = 51.58; df = 1, 5; P = 0.0188) (Fig. 1).Pecan leafroll mite-damaged compound leaves remain on trees through the season. These damaged leaves are photosynthetically active, and the overall reduction in leaflet area is not different between compound leaves with or without pecan leafroll mite injury. Thus, the leaf parameters measured during this study indicated that the level of damage was cosmetic and would not require treatment. These results suggest, however, that pecan leafroll mite damage may increase leaflet water stress. Severe outbreaks of pecan leafroll mite may cause injury at an economic level and so future studies should investigate the relationship of irrigation on tree health and incidence of pecan leafroll mites on pecan canopies.We thank K. Moncrief, R. Hartley, S. Burrell, and M. Bacon (USDA-ARS, Southeastern Fruit and Tree Nut Research Laboratory) for technical assistance. The findings and conclusions in this publication are those of the authors and should not be construed to represent any official USDA or U.S. Government determination or policy.

Xylosandrus crassiusculus (Motschulsky) and Xylosandrus germanus (Blandford) (Coleoptera: Curculionidae: Scolytinae) are major ambrosia beetle pests in tree nut and fruit orchards and ornamental nurseries in the eastern United States (USA). Ethanol-baited bottle traps and ethanol-infused tree stem sections (i.e., bolts) have been used to monitor ambrosia beetles, but limited studies exist on the influence of ethanol-lure release rate on ambrosia beetle trap captures and bolt attacks. We designed this study to compare low-release (LR) and high-release (HR) ethanol lures in bottle traps for capturing invasive ambrosia beetles. We also compared beetle attacks among bolts pre-soaked in ethanol solutions of low (10%) and high (90%) concentrations and bolts cored and filled with the same low and high ethanol concentrations. In 2022, experiments were conducted in ornamental nurseries and apple, peach, or pecan orchards in five USA states. Higher numbers of X. crassiusculus and X. germanus were captured in bottle traps baited with the HR ethanol lure compared to the LR lure at most of the study sites. More attacks per bolt by X. crassiusculus and X. germanus were observed at most sites on pre-soaked and filled bolts with 90% compared to 10% solutions of ethanol. Bolts soaked in low (10%) ethanol solutions sustained more attacks from both X. crassiusculus and X. germanus than cored bolts filled with low ethanol. These results will assist with monitoring the flight activity of invasive ambrosia beetles within nut, fruit, and ornamental tree crops.

The polyphagous pest, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), damages fruit in orchards and field crops and is often found within nearby woodlands. Pheromone-baited traps can be used to monitor H. halys. However, the efficiency of trapping H. halys may vary depending on trapping strategy (live vs. dead capture), location (ground or canopy), and diel periodicity of captures. We compared H. halys capture within fruiting hosts for: (i) live and kill traps on the ground vs. traps in the canopy of black cherry (Prunus serotina Ehrh.) (Rosales: Rosaceae), sugarberry (Celtis laevigata Willdenow) (Rosales: Cannabaceae), and pecan (Carya illinoinensis (Wangenh.) K. Koch) (Fagales: Juglandaceae) trees, (ii) ground and canopy-live traps in sassafras (Sassafras albidum (Nutt.) Nees) (Laurales: Lauraceae), and (iii) whether diel periodicity was detected for live capture in sassafras and cotton. More H. halys adults and nymphs were captured in kill traps than in live traps. More nymphs were captured in kill traps in black cherry and sugarberry on the ground than in the canopy. Live adult capture was significantly greater in sassafras and pecan canopies than on the ground. In cotton and sassafras, more live adults were captured from 8 PM—noon, with the fewest captured from noon—6 PM. A better understanding of stink bug activity in the field allows for improved trapping and, possibly, improved timing of treatment applications.

The pecan nut casebearer, Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae), is a monophagous pest attacking pecan, Carya illinoinensis (Wangenh.) Koch. Pheromone traps attractive to adult males are used to monitor this pest in orchards by placing them in the lower canopy. However, some insects exhibit vertical stratification in tree canopies as does occur for some beneficial and pest species associated with pecan. The objective of this study was to assess vertical stratification of the pecan nut casebearer in the canopy of tall pecan trees when sampling with pheromone traps. Traps were placed at three heights in orchards (1.5, 7.6, and 13.7 m) above ground. In one experiment, only one trap was placed at one of the three heights at a tree. In the other experiment, three traps, one at each height, were placed in the canopy of the same tree. Results from both experiments reveal that the pecan nut casebearer does stratify within the pecan canopy. Significantly more moths were captured in the highest trap than in the traps at the other heights. These results provide information useful for developing pecan nut casebearer management strategies such as mating disruption in pecan orchards with tall trees.

Pecan (Carya illinoinensis) is an important specialty crop in the U.S.A., but yield is limited by several diseases and pests. In mature-tree pecan orchards, large air-blast sprayers are commonly used to apply the pesticides to control these diseases and pests. The spray coverage, deposition and profiles are poorly defined under the range of application scenarios, limiting the recommendations that can be provided to growers to maximize control while minimizing input costs. To explore effects of sprayer setting parameters such as travel speed and spray volume rate on spray coverage on tall targets we set up a system (a simple vertical patternator) using a 19-m-tall pole with cards attached at eight height levels from 5 to 19 m above ground, allowing to determine the vertical distribution pattern of two air-blast sprayers with different air discharge systems. Spray was applied with a standard radial-flow air-blast sprayer during six treatments being combinations of two travel speeds: 2.4 and 3.2 km/h, and three spray volume rates: 470, 940 and 1970 L/ha, as well as with a focused air-flow system (a volute) sprayer during four treatments being combinations of two travel speeds: 2.4 and 3.2 km/h, and two spray volume rates: 470 and 940 L/ha. Results show that using a standard radial air-flow sprayer, application volume affected coverage at heights <= 17 m (higher volumes resulting in more coverage). Higher speed using a standard radial air-flow sprayer resulted in greater spray coverage, but was inconsistent with the focused air-flow system. Using a focused air-flow system more spray coverage occurred at >17 m compared to a standard radial air-flow sprayer. Spray coverage profiles affirmed the rapid decline in coverage with height using a standard radial air-flow sprayer. The results may help guide decisions on volute use, spray volume, and spray partitioning to different parts of the canopy to improve spray profile characteristics for applying more uniform spray coverage to mature pecan tree canopies.

In many agroecosystems, brown marmorated stink bugs (Halyomorpha halys) (Hemiptera: Pentatomidae) are polyphagous pests that cause significant economic losses to numerous crops every year. Insectivorous birds may provide a means of sustainable predation of invasive pests, such as H. halys. In forest margins surrounding peach, pecan, and interplanted peach–pecan orchards, we monitored H. halys populations with pheromone-baited traps, mist-netted birds, and collected avian fecal samples for molecular gut content analysis. We screened 257 fecal samples from 19 bird species for the presence of H. halys DNA to determine whether birds provide the biological control of this pest. Overall, we found evidence that four birds from three species consumed H. halys, including Northern cardinal (Cardinalis cardinalisis), Tufted titmouse (Baeolophus bicolor), and Carolina wren (Thryothorus ludovicianus). Halyomorpha halys captured in traps increased over time but did not vary by orchard type. Although incidence of predation was low, this may be an underestimate as a result of our current avian fecal sampling methodology. Because birds are members of the broader food web, future studies are needed to understand avian ecosystem services, especially in terms of pest control, including H. halys and other pest species.

Stink bugs, including Halyomorpha halys (Stål) and Nezara viridula (L.), are agricultural pests that feed on fruit in a variety of crops. Monitoring predation and parasitism of stink bug egg masses furthers our understanding of potential biological control tactics. However, best practices for laboratory and field assessments of parasitism and predation of egg masses require further attention. We carried out a series of laboratory and field experiments to test whether parasitism and predation for three types of sentinel H. halys egg masses, fresh, frozen, and refrigerated, varied in agricultural commodities. In addition, we asked if predation and parasitism differed between sentinel and naturally occurring H. halys and N. viridula egg masses in soybean. In the laboratory, more H. halys eggs were parasitized by Trissolcus euschisti (Ashmead) (Hymenoptera: Scelionidae) if they were frozen or refrigerated compared to fresh eggs. Similarly, in the field, parasitism was higher for frozen egg masses than fresh. In 2018 and 2019, H. halys natural egg masses had higher parasitism and lower predation compared to sentinel egg masses in soybean. In a paired field test during 2020 and 2021, there was no difference in parasitism between H. halys natural and sentinel eggs, but much higher incidence of parasitism was detected in natural N. viridula egg masses than sentinel eggs. Collecting natural egg masses is the best methodology for field assessment of parasitism of stink bug egg masses; however, if natural egg masses are not easily available, deploying refrigerated sentinel egg masses is a good alternative.