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The Nantucket pine tip moth (NPTM) (Rhyacionia frustrana Comstock) is a native, regeneration pest of young loblolly pines (Pinus taeda L.), causing shoot dieback, tree deformity, and growth and volume declines. Soil applications of systemic insecticides may be an effective strategy to suppress NPTM populations. The study objective was to assess the efficacy of four systemic insecticide treatments (chlorantraniliprole, dinotefuran, fipronil, and imidacloprid) for two growing seasons in outplanted bareroot and containerized seedling trials. Response variables included NPTM infestation rates, along with tree height, groundline diameter, volume index, and stem form. Infestation rates significantly decreased for each systemic insecticide treatment during the first year compared to controls, although dinotefuran and imidacloprid provided season-long control in one trial. Chlorantraniliprole reduced NPTM infestation rates for two growing seasons in both trials. While imidacloprid treatments did not alter growth metrics except for one comparison, fipronil and dinotefuran treatments improved several growth metrics. Chlorantraniliprole consistently improved growth metrics throughout the study. [ABSTRACT FROM AUTHOR]

Forest insect pest phenology and infestation pressure may shift as temperatures continue to warm due to climate change, resulting in greater challenges for sustainable forest management. The Nantucket pine tip moth (NPTM) (Rhyacionia frustrana Comstock) (Lepidoptera: Tortricidae) is a native forest regeneration pest in the southeastern U.S. with multiple generations per year. Changes in NPTM voltinism may result from temperature-induced shifts in NPTM phenology. Degree-day models have been used to develop optimal spray dates (OSDs) for NPTM. The 2000 Spray Timing Model (STM), based on temperature data from 1960 to 2000, provided generation-specific 5-d OSDs to effectively time applications of contact insecticides. An updated degree-day model, the 2019 STM, is based on temperature data from 2000 to 2019 and was used to detect changes in voltinism as well as shifts in phenology and OSDs. Based on the model, increased voltinism occurred at 6 of the 28 study locations (21%). Changes in voltinism occurred in the Piedmont and Coastal Plain of Georgia, U.S. with shifts from three to four or four to five generations a year, depending on location. The OSDs from the 2019 STM were compared to the 2000 STM OSDs. Over half (57%) of the OSDs differed by 5–15 d, with the majority (66%) resulting in earlier spray dates. The 2019 STM will help growers adapt NPTM control tactics to temperature-induced phenology shifts. NPTM serves as an example of temperature-induced changes attributed to climate change in a forest insect pest with important implications to forest management. [ABSTRACT FROM AUTHOR]

The Nantucket pine tip moth (NPTM) [ Rhyacionia frustrana (Comstock)], a native regeneration pest on young loblolly pines (Pinus taeda L.), negatively impacts pine growth. An emerging management approach is to apply systemic insecticides to seedlings to reduce NPTM damage. These systemic insecticide applications generally occur once, perhaps twice, during the first few years of loblolly pine growth. However, these applications could lead to unintended environmental consequences to nontarget organisms. The purpose of this study was to assess potential nontarget effects from four systemic insecticide applications by assessing ground-dwelling arthropod trap catch, with a focus on collembolan trap catch and genera richness. Loblolly seedlings (24 seedlings per plot) at three sites in southeast Georgia were treated with either chlorantraniliprole, dinotefuran, fipronil, or imidacloprid or left untreated as a control. Arthropods were collected with pitfall traps that were deployed for 5 d in July, August, and September 2019, 7–9 mo after treatment. Ground-dwelling arthropod trap catch, arthropod order trap catch, collembolan trap catch, and collembolan genera richness did not vary among insecticide treatments and the untreated control in this mid-term insecticide risk assessment. While no significant effects of insecticide treatment were observed, ground-dwelling arthropod trap catch, collembolan trap catch, and collembolan genera richness differed among collection times. This study was the first of its kind in a young pine stand setting and is an important first step to understanding risk in these settings. Information on nontarget risks of management practices informs growers of the level of environmental risk associated with systemic insecticides. [ABSTRACT FROM AUTHOR]

We determined the response of the small southern pine engraver, Ips avulsus (Eich- hoff); eastern fivespined ips, Ips grandicollis (Eichhoff); sixspined ips, Ips calligraphus (Germar); and pine engraver, ips pini (Say) to the pheromones (±) -ipsenol, (±) -ipsdienol, and lanierone in the southeastern United States. Catches of I. avulsus and I. grandicollis to baited multiple-funnel traps were increased by (±) -ipsenol and (±) -ipsdienol in Florida, Georgia, Louisiana, and North Carolina. In all four localities, the highest numbers of I. avulsus were caught in traps baited with the combination of (±) -ipsenol, (±) -ipsdienol, and lanierone. In Florida, the highest numbers of I. grandicollis were captured in traps baited with the combination of (±) -ipsenol and (±) -ipsdienol (with or without lanierone). In the remaining three localities, the largest catches of I. grandicollis occurred in traps baited with (±) -ipsenol alone or the combination of (±) -ipsenol and (±) -ipsdienol (with or without lanierone). (±) -Ipsdienol was the only consistent attractant for I. calligraphus and I. pini. Attraction of I. pini in North Carolina to (±) -ipsdienol-baited traps was synergized by lanierone but interrupted with (±) -ipsenol. The interruptive effect of (±) -ipsenol on attraction of I. pini to (±) -ipsdienol was negated by lanierone. (±) -Ipsdienol was attractive to black turpentine beetle, Dendroctonus terebraris (Olivier), in Florida but not North Carolina, whereas (±) -ipsdienol was attractive to L calligraphus in Louisiana, Georgia, and Florida. Both (±) -ipsenol and (±) -ipsdienol affected catches of Gnathotrichus materiarus (Fitch) in North Carolina. Trap catches of Hylurgops rugipennis pinifex (Fitch), Hylastes salebrosus Eichhoff, and Hylastes tenuis Eichhoff were unaffected by the pheromone treatments. The combination of (±) -ipsenol, (±) -ipsdienol, and lanierone may be a cost-effective general lure for I. avulsus, I. grandicollis, and I. pini. [ABSTRACT FROM AUTHOR]

We determined the responses of the southern pine sawyer, Monochamus titillator (F.) (Coleoptera: Cerambycidae), to the pheromones (ipsenol, ipsdienol, and lanierone) used by pine engraver beetles (Coleoptera: Scolytidae) in the southeastern United States. (±) -Ipsenol, (±) - ipsdienol, or a combination increased catches of M. titillator in Florida, Louisiana, Georgia, and North Carolina. Catches of Acanthocinus obsoletus (Olivier) (Cerambycidae) were increased by (±)-ipsenol and (±) -ipsdienol in Florida and North Carolina, whereas only (±) -ipsenol was attractive in Georgia (±) -Ipsenol and (±) -ipsdienol were attractive to Pachylobius picivorus (Germar) (Coleoptera: Curculionidae) in Florida, whereas only (±) -ipsdienol was active in Louisiana In Florida, catches of M. titillator, A. obsoletus, and P. picivorus were greatest in traps baited with both (±) -ipsenol and (±) -ipsdienol. In Louisiana, catches of the woodborer Chalcophora virginiensis (Drury) (Buprestidae) were increased by (±)-ipsenol. Lanierone did not affect trap catches of the aforementioned species. The combination of (±) -ipsenol and (±) -ipsdienol may be a cost-effective lure for these four species because we found no evidence of interruption in attraction to baited traps, and the cost of the lure combination is relatively low. [ABSTRACT FROM AUTHOR]