Predators attracted to combination of bark beetle pheromones and host kairomones in pine forests of southeastern United States.

In 2006, we evaluated the effects of combining lures releasing pine host kairomones (ethanol + α-pinene) with lures releasing bark beetle pheromones (ipsenol + ipsdienol) on trap catches of predators associated with bark and woodboring beetles in Florida, Georgia, Louisiana, and Virginia. Catches in traps baited with all 4 compounds were greater than those in traps baited with either binary blend for the common predators Thanasimus dubius (F.) (Coleoptera: Cleridae), Temnoscheila virescens (F.) (Coleoptera: Trogossitidae), Aulonium tuberculatum LeConte (Coleoptera: Zopheridae), and Lasconotus spp. (Coleoptera: Zopheridae). The same was true for: Enoclerus nigripes (Say) (Coleoptera: Cleridae) at 2 of 3 locations; Platysoma cylindricum (Paykull) (Coleoptera: Histeridae) at 3 of 4 locations; and Corticeus spp. (Coleoptera: Tenebrionidae) at 2 of 6 locations. In contrast, the addition of ethanol + α-pinene to traps baited with ipsenol + ipsdienol reduced catches of Platysoma attenuatum LeConte (Coleoptera: Histeridae) at 2 of 4 locations.

Denser forests across the USA experience more damage from insects and pathogens.

Forests across much of the United States are becoming denser. Trees growing in denser stands experience more competition for essential resources, which can make them more vulnerable to disturbances. Forest density can be expressed in terms of basal area, a metric that has been used to assess vulnerability of some forests to damage by certain insects or pathogens. A raster map of total tree basal area (TBA) for the conterminous United States was compared with annual (2000-2019) survey maps of forest damage due to insects and pathogens. Across each of four regions, median TBA was significantly higher within forest areas defoliated or killed by insects or pathogens than in areas without recorded damage. Therefore, TBA may serve as a regional-scale indicator of forest health and a first filter for identifying areas that merit finer-scale analysis of forest conditions.

Past and present individual-tree damage assessments of the US national forest inventory.

Identifying the signs and symptoms of pathogens, insects, and other biotic and abiotic agents provides valuable information about the absolute and relative impacts of different types of damage across the forest landscape. In the USA, damage collection protocols have been included in various forms since the initiation of state-level forest surveys in the early twentieth century; however, changes in the protocols over time have made it difficult for the data to be used to its full potential. This article outlines differences in protocols across inventory regions, changes in protocols over time, and limitations and utility of the data so that those interested in using the US national forest inventory database will better understand what data are available and how they have been and can be used.

Matsucoccus macrocicatrices (Hemiptera: Matsucoccidae): first report, distribution, and association with symptomatic eastern white pine in the southeastern United States.

We provide the first report of Matsucoccus macrocicatrices Richards (Hemiptera: Matsucoccidae) feeding and reproducing on eastern white pine, Pinus strobus L., in the southeastern United States. Until now, M. macrocicatrices had been reported only from the Canadian Atlantic Maritimes, New Hampshire, and Massachusetts. Entomological holdings of 27 major museums in eastern North America have no historical records for M. macrocicatrices from the southeastern region. However, our field surveys and molecular analyses (DNA barcoding) have resulted in the collection and positive identification of M. macrocicatrices in Georgia, North Carolina, South Carolina, Tennessee, Virginia, and West Virginia In addition to the new geographic range, M. macrocicatrices is also being associated with dieback and mortality of all diameter classes of P. strobus leading to concern about a potential shift from its historically nonpestiferous presence on the host tree. On P. strobus, M. macrocicatrices was found embedded in cankers or present on top of the bark with necrotic tissue under their feeding area, indicating that they may be creating wounds for opportunistic pathogenic fungi to infest. Further, we found M. macrocicatrices living outside of the epiphytic mats of its symbiotic fungus, Septobasidium pinicola Snell. This study shows that M. macrocicatrices is now widespread in the southeastern United States, with implications for the future survival and regeneration of P. strobus in eastern North America.

Use of systemic fipronil and imidacloprid to control regeneration pests of loblolly pine.

Regeneration pests of loblolly pine (Pinus taeda L.) threaten growth and survival in intensively managed loblolly pine plantations throughout the southeastern United States. The Nantucket pine tip moth, Rhyacionia frustrana (Comstock), in particular, often reduces growth of loblolly pine but has been difficult to control with traditional insecticides due to multiple annual generations and multi-year infestations which are difficult to predict in timing and location. Relatively new systemic insecticide products offer a solution in that their efficacy persists through multiple generations and years after a single application. Efficacy of systemic imidacloprid and fipronil were evaluated side by side across multiple sites in Virginia. Significant reductions in Nantucket pine tip moth damage were noted in trees treated with either the imidacloprid or fipronil product compared with check trees. After 2 yr, growth improvement of treated trees relative to controls was modest and not significant at all sites, but per acre volume indices were significantly greater in treated blocks as a result of higher tree survival. Reduced seedling mortality was attributed primarily to prevention of damage by pales weevil, Hylobius pales Herbst (Coleoptera: Curculionidae), by both insecticide treatments. Control of pales weevil in addition to pine tip moth suggests that systemic insecticide products with a long window of efficacy might control additional nontargeted pests.

Dose and enantiospecific responses of white pine cone beetles, Conophthorus coniperda, to alpha-Pinene in an eastern white pine seed orchard.

The white pine cone beetle, Conophthorus coniperda, exhibited dose and enantiospecific responses to alpha-pinene in stands of mature eastern white pine, Pinus strobus, in a seed orchard near Murphy, North Carolina, USA. (-)-alpha-Pinene significantly increased catches of cone beetles to traps baited with (+/-)-trans-pityol. (+)-alpha-Pinene did not increase catches of beetles to pityol-baited traps and interrupted the response of beetles to traps baited with (+/-)-trans-pityol and (-)-alpha-pinene. Maximal attraction of cone beetles to pityol-baited traps was obtained with lures releasing (-)-alpha-pinene at a rate of 103 mg/day at 23 degrees C. Lures releasing (-)-alpha-pinene at rates lower or higher than 103 mg/day resulted in reduced catches to traps baited with (+/-)-trans-pityol. The sex ratio in all catches was heavily male biased. Attraction of the clerid predator, Thanasimus dubius, to traps baited with (+/-)-trans-pityol increased significantly with the presence of alpha-pinene, irrespective of enantiomeric composition. Maximal attraction of T. dubius to pityol-baited traps occurred with devices releasing (-)-alpha-pinene at the highest rate tested, 579 mg/d at 23 degrees C, a sub optimal rate for cone beetles.