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Addressing the risk from pests present in wood and wood products destined for international trade is an essential step towards minimizing the movement, introduction and establishment of invasive species. One method of managing the pest risk associated with wood commodities is the use of a systems approach that incorporates multiple independent measures applied along a production pathway. However, quantifying the reduction of risk can be difficult because the approach requires raw material infested with the pest of interest at a sufficient density to be able to quantify changes in pest abundance. We tested a systems approach for the production of sawn wood using green ash, Fraxinus pennsylvanica Marshall (Lamiales: Oleaceae), infested with emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), by quantifying the change in pest density during the milling process and the precise effect of heat treatment on insects in situ. Greater than 90% of emerald ash borer were removed at the first step of the milling process (debarking) and >99% were removed before the production of green sawn wood. No insects survived kilning or heat treatment. All life stages of emerald ash borer were killed at 56°C and above. Heat, however, had no sublethal effect on emerald ash borer performance. These results show that the application of a systems approach to mitigate emerald ash borer in heat-treated, sawn wood is effective. Moreover, the model-system approach developed in this study can be a template for investigating the effect of systems approaches for other phloem-feeding insects.

We examined the suitability of cultivated olive, Olea europaea L., as a host for emerald ash borer, Agrilus planipennis Fairmaire. In a bioassay using cut stems from a field-grown olive tree (cv. 'Manzanilla') we found that 45% of larvae that had emerged from eggs used to inoculate stems, were recovered alive, many as larvae or prepupae, during periodic debarking of a subset of stems. Three intact stems that 19 larvae successfully entered were exposed to a simulated overwintering treatment. Four live adults emerged afterwards, and an additional pupa and several prepupae were discovered after debarking these stems. Cultivated olive joins white fringetree as one of the two species outside of the genus Fraxinus capable of supporting the development of emerald ash borer from neonate to adult.

Palpita forficifera Munroe, 1959 (Lepidoptera: Crambidae) is the main pest of the olive tree (Olea europaea L. Oleaceae) in Brazil. This study investigated the biology of P. forficifera reared on different hosts and elaborated the corresponding fertility life table for a better understanding of its development. Biology of P. forficifera was studied using olive cultivars Arbequina, Arbosana and Koroneiki and the alternative host privet (Ligustrum lucidum Ait., Oleaceae), under controlled conditions of temperature (25 ± 2°C), relative humidity (60 ± 10%), and photophase (14 h). We evaluated duration and viability of egg, larva, and pupa stages; number and duration of instars; sex ratio; pupa weight; duration of preoviposition, oviposition, and postoviposition periods; fecundity and longevity. The fertility life table was elaborated from these parameters. Larvae fed with privet had longer larval stage, and consequently, egg-pupa period. Larva viability was lower in cv. Arbosana, which reflected in lower viability in the egg-pupa period. Larvae fed with cv. Koroneiki originated females with higher fecundity. From the joint assessment of the biological parameters and the fertility life tables, cv. Koroneiki provided the greatest population increase, while cv. Arbosana impaired P. forficifera development. Thus, in areas of high occurrence of this species, cv. Arbosana should be considered as the more indicated cultivar for the establishment of new olive groves.

Emerald ash borer (EAB), Agrilus planipennis (Fairmaire; Coleoptera: Buprestidae), is decimating ash trees (Fraxinus spp.) in North America. Combatting EAB includes the use of insecticides; however, reported insecticide efficacy varies among published studies. This study assessed the effects of season of application, insecticide active ingredient, and insecticide application rate on green ash (Fraxinus pennsylvanica Marsh.) (Lamiales: Oleaceae) canopy decline caused by EAB over a 5- to 7-yr interval. Data suggested that spring treatments were generally more effective in reducing canopy decline than fall treatments, but this difference was not statistically significant. Lowest rates of decline (

Emerald ash borer is an invasive Asian pest of ash species in North America. All North American species of ash tested so far are susceptible to it, but there are no published reports of this insect developing fully in non-ash hosts in the field in North America. I report here evidence that emerald ash borer can attack and complete development in white fringetree, Chionanthus virginicus L., a species native to the southeastern United States that is also planted ornamentally. Four of 20 mature ornamental white fringetrees examined in the Dayton, Ohio area showed external symptoms of emerald ash borer attack, including the presence of adult exit holes, canopy dieback, and bark splitting and other deformities. Removal of bark from one of these trees yielded evidence of at least three generations of usage by emerald ash borer larvae, several actively feeding live larvae, and a dead adult confirmed as emerald ash borer.

Using the age-stage, two-sex life table, the effects of three ligustrum species, Ligustrum x vicaryi Hort., Ligustrum quihoui Carriere, and Ligustrum lucidum Aiton, on the fitness of Problepsis superans (Butler, 1885) (Lepidoptera: Geometridae) were assayed by considering life table parameters of P. superans at 27 +/- 1 degrees C, 70 +/- 5% relative humidity, and a photoperiod of 16:8 (L: D) h. The means and SEs of population parameters were calculated using the jackknife and bootstrap methods. The total developmental time of larval stage of P. superans on L. x vicaryi was significantly shorter than that on L. x vicaryi and L. quihoui, whereas higher fecundity was observed on L. x vicaryi. The highest value of the finite rate of increase was observed on L. x vicaryi. The intrinsic rate of increase of P. superans on L. x vicaryi, L. quihoui, and L. lucidum, was 0.147 +/- 0.004, 0.130 +/- 0.004, and 0.112 +/- 0.005, respectively, which differed significantly among the three ligustrum species. The net reproductive rate varied from 122.8 +/- 24.7 female offspring on L. lucidum to 242.2 +/- 36.2 female offspring on L. x vicaryi. The lowest mean generation time was observed on L. x vicaryi. The gross reproductive rate of P. superans on the three ligustrum species did not significantly differ. Based on growth and population parameters, the suitability of the three ligustrum species to P. superans is ranked from high to low in the order as L. x vicaryi, L. quihoui, and L. lucidum.

We conducted field trials at five different locations over a period of 6 yr to investigate the efficacy of imidacloprid applied each spring as a basal soil drench for protection against emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae). Canopy thinning and emerald ash borer larval density were used to evaluate efficacy for 3-4 yr at each location while treatments continued. Test sites included small urban trees (5-15 cm diameter at breast height [dbh]), medium to large (15-65 cm dbh) trees at golf courses, and medium to large street trees. Annual basal drenches with imidacloprid gave complete protection of small ash trees for three years. At three sites where the size of trees ranged from 23 to 37 cm dbh, we successfully protected all ash trees beginning the test with60% canopy thinning. Regression analysis of data from two sites reveals that tree size explains 46% of the variation in efficacy of imidacloprid drenches. The smallest trees (30 cm dbh) remained in excellent condition for 3 yr, whereas most of the largest trees (38 cm dbh) declined to a weakened state and undesirable appearance. The five-fold increase in trunk and branch surface area of ash trees as the tree dbh doubles may account for reduced efficacy on larger trees, and suggests a need to increase treatment rates for larger trees.

Chinese privet, Ligustrum sinense Lour., is a perennial semi-evergreen shrub that is a serious invasive weed in the United States. Classical biological control offers the best hope for controlling it in an economic, effective, and persistent way. Host specificity of one of the most promising biological control agents of Chinese privet, a flea beetle, Argopistes tsekooni Chen (Coleoptera: Chrysomelidae), was evaluated in China by using laboratory no-choice and choice tests on 13 species of Oleaceae and eight species in other families that have important economic value. In adult no-choice survival and oviposition tests, the flea beetle fed and survived for 30 d on Syringa oblata Lindl., Jasminum nudiflorum Lindl., and three species in the genus Ligustrum. Females also oviposited on these species, but only larvae from eggs laid on S. oblata and Ligustrum spp. developed successfully. In addition, the beetles did not feed or oviposit on the species of economic importance. In choice tests, adults preferred L. sinense for feeding and oviposition. These results show that A. tsekooni is relatively host specific and warrants further testing as a biocontrol agent of Chinese privet in the United States.

The emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), a phloem-feeding insect from Asia, was identified in 2002 as the cause of widespread ash (Fraxinus sp.) mortality in southeastern Michigan and Essex County, Ontario. Most larvae overwinter as nonfeeding prepupae in the outer sapwood or thick bark of large trees. In a series of studies, we evaluated effects of grinding, chipping, and heat treatment on survival of A. planipennis prepupae in ash material. Heavily infested ash bolts containing roughly 8,700 prepupae were processed by a horizontal grinder with either a 2.5- or 10-cm screen. There was no evidence of A. planipennis survival in chips processed with the 2.5-cm screen, but eight viable prepupae were recovered from chips processed with the 10-cm screen. We chiseled additional sentinel chips with prepupae from ash logs and buried 45 in each chip pile. In total, six prepupae in sentinel chips survived the winter, but we found no sign of adult A. planipennis emerge...

The seasonal population abundance of Rhynchites cribripennis (Desbrochers) adults on olive trees was studied by collecting samples from an olive grove on the island of Zakynthos, Greece, from April 1994 to the end of July 1995. Moreover, the population abundance of larvae, pupae, and adults of R. cribripennis was recorded in soil samples from two soil depths (0-4 and 4-8 cm) from October 1994 to October 1995. Results showed that adult populations increased considerably on trees during May and June and peaked on 16 June (19.9 adults per twig) and 8 July (7.7 adults per twig) in 1994 and 1995, respectively. In 1994, no significant differences were found in the number of adults sampled from the different tree quadrants (northwest [NW], northeast [NE], southwest [SW], and southeast [SE]). However, in 1995, adult numbers in the NW quadrant of trees were significantly higher than those in the SE or SW quadrants. In soil samples, larvae were recorded throughout the sampling period with the highest numbers occurring in December, 2.4 larvae per soil sample, whereas pupae were found in lowest numbers in October and November. Adults were present in the soil samples from December to May, but the highest numbers were recorded in December, with a peak of one adult per sample. The number of adults was significantly higher, and that of larvae numerically higher, in the upper compared with lower soil layer, whereas pupae were found with similar numbers in both soil layers. Results of these studies suggest that this weevil exhibits a prolonged larval diapause and a 2-yr life cycle. The ecological implications of this behavior are discussed. Moreover, a prediction of the highest adult population on trees was estimated by taking into account the rate of increase of adult numbers in the early period of adult occurrence on trees.

The moth Lymantria mathura Moore is a polyphagous defoliator of forest and fruit trees in the Russian Far East, Japan, India, and China, and it would cause serious economic consequences if established in North America. To project the host range of this insect if accidentally introduced into North America, we examined survival and development of 1st instars of L. mathura on 24 broadleafed and conifer tree species from North America, Europe, and Asia. L. mathura performed well on hosts in the family Fagaceae regardless of the species origin. Survival and rate of development on European beech, Fagus grandifolia Ehrh., and American beech, Fagus syLvatica L., was equivalent to survival on oriental oak, QlIercus variabilis Blume. Performance of larvae was also high on white oak, Quercus alba L., and chestnut oak, Quercus prinus L. Suitability of other oaks, such as red oak, Quercus rubra L., black oak, Quercus velutina Lamarck, and pin oak, Quercus palustris Muenchh., was intermediate and equivalent to suitability of species from the families Juglandaceae, Betulaceae, and Oleaceae. Survival was poor on hosts from Aceraceae and Pinaceae. Comparison of host preferences and larval survival of L. mathura and of the gypsy moth, Lymantria dispar (L.), indicates differences between these species when tested on the same or congeneric host plants.

The amount of olive surface waxes obtained from fruits belonging to 5 Greek cultivars ranged from 11.6 to 152.9 mg/100 g fruit. It varied significantly among varieties during fruit growth and maturation throughout the season, with 2 peaks around mid-August and the end of September up to mid-October. The 2 pentacyclic triterpene acids, oleanolic and maslinic, constituted the highest percentage of the total surface wax composition and were present in comparable amounts. The number of eggs oviposited varied significantly under treatments with different wax solutions compared with controls, which showed the highest mean in egg number (6.4 eggs per fruit). Highly significant negative correlations were detected among the concentrations of the oleanene acids and the number of eggs oviposited; the correlation factor (R) was -0.76 for oleanolic acid and -0.62 for maslinic acid. Oleanolic acid had a dominant effect over maslinic acid. Choice experiments showed that the degree of infestation of olive fruits by B. oleae was affected by the type of cultivar and the degree of olive fruit maturation. The size of olive fruit was not significant in determining the preference of B. oleae for ovipositing.

The key to an effective pest management program for the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera Buprestidae), is a survey program equipped with tools for detecting and delimiting populations. We studied the effects of trap design, color, and placement on the efficacy of sticky traps for capturing the emerald ash borer. There were significant differences in trap catch along a transect gradient from wooded to open field conditions, with most beetles being caught along the edge, or in open fields, 15-25 m outside an ash (Fraxinus spp. L.) (Oleaceae) woodlot. Greater emerald ash borer catch occurred on purple traps than on red or white traps. Traps placed in the mid-canopy of ash trees (13 m) caught significantly more beetles than those placed at ground level. We also describe a new trap design, a three-sided prism trap, which is relatively easy to assemble and deploy.

The olive fruit fly, Bactrocera oleae (Gmelin) (Diptera: Tephritidae), is an invasive pest of olives (Olea spp.) in the United States. The objectives of this study were to determine whether B. oleae exhibits ovipositional preference under California field conditions similar to that demonstrated in European populations and whether the resulting larvae fare better in preferred varieties. Female B. oleae exhibited strong ovipositional preference for certain varieties of the domesticated olive, Olea europaea L, and the resulting larvae performed better by some measures in preferred varieties than in lesser preferred varieties. Ovipositional preference was observed in the field from 2003 to 2005, and laboratory assays were conducted to evaluate larval performance in 2005 and 2006. Among the olive varieties tested, Sevillano, Manzanillo, and Mission olives were the most heavily infested during three consecutive years. The larval performance measurements used were pupal yield, pupal weight, larval developmental time, and pupal emergence time. Ovipositional preference and pupal yield do not seem associated. There were significant differences in pupal emergence time, but these also measures did not reflect ovipositional preference. Two measures on performance did seem related to ovipositional preference; there were significant effects of variety on pupal weight and larval developmental time. Pupae developing in Manzanillo and Sevillano olives were heavier than those developing in less preferred varieties, and larval developmental time was significantly shorter in Sevillano olives relative to the other varieties. Oviposition preference and enhanced larval performance has implications for the pest status of this invasive insect in California.