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During 2017 and 2018, gardeners at 36 locations across 21 Georgia counties volunteered to be part of the Georgia Pollinator Census project. The goals of the project were to generate a snapshot of pollinator population data while educating gardeners about the importance of pollinators and other beneficial insects and assisting schools with science, technology, engineering, art, and math programming. Effective insect identification training and on-going support were crucial parts of this citizen science project. Insect counting was conducted in September and October on an aster species and another plant species chosen by the participants. Twenty-eight plant taxa were chosen by participants to be frequently visited by pollinators. Analysis of the data indicates a higher number of sightings of bumble bees, Bombus spp. Latrelle (Hymenoptera: Apidae); honey bees, Apis mellifera L. (Hymenoptera: Apidae), and wasps (Hymenoptera: Vespidae) in rural areas and a higher number of sightings of carpenter bees, Xylocopa spp. Latrelle (Hymenoptera: Apidae); flies (Diptera); and “other insects” (e.g., those that did not fall into any of the other seven categories) in urban areas. We also saw an increase in entomological interest among the participants as well as an increase in insect knowledge. This pilot project was used to refine criteria for a larger state-wide census.

Insect nesting boxes and hotels have the potential to provide shelter and overwintering sites for beneficial insect communities such as pollinating bees, wasps, earwigs, and other predatory arthropods. This study evaluated beneficial arthropod visitation to consumer-ready, commercially available nesting boxes over a 2-yr period. Insect hotels were placed on mature river birch (Betula nigra L.) and crape myrtle (Lagerstroemia indica L.) in garden plots established with floral resources for pollinators and other beneficial insects. Paper and thread-waisted wasps, soldier flies, predatory ants, and spiders were observed visiting the boxes. Boxes located in garden plot treatments (with floral resources) had the greatest numbers and diversity of pollinator and beneficial insect taxa compared to control plot treatments (naturalized areas away from floral resources) in 2016. Insect hotels placed on B. nigra had a higher number of thread-waisted wasps in 2016 and spiders and total beneficial insects in 2017. Higher numbers of predatory ants and total beneficial arthropods were found in boxes placed on L. indica in 2016. During the study, bamboo stems and drilled tunnels in the insect boxes were evaluated for arthropod inhabitance. Largest counts of occupied stems and tunnels were observed in boxes placed in proximity to floral resources and on L. indica trees.

Growth and developmental parameters of the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), were evaluated on 41 new zoysiagrass taxa (Zoysia spp. Willd.), which belong to an increasingly popular group of warm-season turfgrasses, in comparison with 5 commercially available zoysiagrass taxa and 1 known susceptible Paspalum L. taxon. Results from two no-choice growth chamber trials indicated that the new Zoysia japonica Steud. taxa were unfavorable for the development of fall armyworm larvae in general compared with the susceptible Paspalum taxon. This was evidenced by significantly lower larval and pupal weights and survival and longer time to pupation and adult emergence, pointing to antibiosis in these zoysiagrass taxa. The new Zoysia matrella (L.) Merr., Zoysia macrostachya Franch. & Sav., and Zoysia sinica Hance taxa seemed more favorable than Z. japonica taxa, as evidenced by numerically higher larval and pupal weights and survival and shorter duration to pupation and adult emergence. Taxa that consistently showed low larval survival were identified for further testing.

Thesquash bug, Anasa tristis (DeGeer), is an indigenous pest of squash, Cucurbita pepo L., and other cucurbits. Geocoris punctipes (Say) adults were collected from stands of mixed grasses in Spalding County, GA, held without food for 24 h, and presented A. tristis eggs, first instars, or second instars in no-choice tests. Consumption of first and second instars was significantly greater by females than by males. Egg consumption was very low with no difference between males and females (P > 0.05). Male G. punctipes consumed a range of 0 to 3 first-instar squash bugs, 0 to 6 second-instar squash bugs, and 0 eggs during the 72-h exposure. Females consumed a range of 0 to 10 first-instar squash bugs, 0 to 10 second-instar squash bugs, and a range of 0 to 1 eggs. Male G. punctipes consumed on average 1.08 ± 0.24 first-instar squash bugs, 1.68 ± 0.41 second-instar squash bugs, and 0 eggs during the 72-h exposure. Females consumed on average 4.12 ± 0.56 first-instar squash bugs, 4.28 ± 0.56 second-instar squash bugs, and 0.12 ± 0.06 eggs. Background mortality for first and second instars was similar and exceeded that for eggs in control, male, and female trials. Previous research demonstrated seasonal overlap in squash bug nymphs and G. punctipes occurrence. These data suggest that G. punctipes can contribute to the suppression of early-season squash bug populations.

The native lace bug, Leptoypha mutica Say (Hemiptera: Tingidae), has demonstrated potential as an insect biological control agent of invasive Chinese privet (Ligustrum sinense Lour). To better evaluate its potential to establish on a new host, developmental biology on Chinese privet was studied at temperatures of 20°C, 24°C, 28°C, and 32°C. The complete duration of development of L. mutica from egg deposition through five instars on this previously unreported host ranged from 24.4 to 57.1 d. Estimated threshold temperatures and calculated thermal unit requirements for egg development were 11.0°C and 211.9 degree-days (DD); for nymphal development, 9.9°C and 326.8 DD; and for complete development, 10.5°C and 527.4 DD. Results of this study indicate that L. mutica will oviposit and can develop successfully on Chinese privet over a range of temperatures suggesting the potential for multiple generations to occur in a single season.

Exotic lace bugs (Hemiptera: Tingidae) have previously been evaluated for potential biocontrol of pervasive, exotic Chinese privet, Ligustrum sinense Lour. This study was conducted to determine if a native lace bug, Leptoypha mutica Say, could utilize Chinese privet and to determine the lace bug's preferred host plant. A no-choice test determined the lace bug's acceptance and utilization of three plant hosts: fringe tree (Chionanthus virginicus L.), swamp privet (Foresteria acuminata Michx), and Chinese privet, based on frass production, oviposition, and survival of lace bugs. Choice tests in the laboratory and the field evaluated lace bug preference among swamp privet, Chinese privet, and green ash (Fraxinus pennsylvanica Marsh). All plant hosts supported the lace bugs in laboratory assays, but fewer eggs were produced on Chinese privet. Green ash was the most preferred while Chinese and swamp privet were equally preferred. These laboratory results were consistent with a field choice test and f...

Flowering ornamental plant species have the potential to support beneficial insect communities such as pollinating bees, wasps, and predatory plant bugs. We compared pan trap color, size, and placement height for sampling of insects in replicated conservation gardens planted with species selected to act as a conservation resource for pollinators and other beneficials. Of the 14 combinations of color, size, and height placement, yellow bowls (14.5-mm diam., 8.5 mm high) placed on the soil substrate captured the greatest numbers and diversity of pollinator and beneficial insect taxa. During the study, 16 species of bees were collected and identified, with Lasioglossum (Dialictus) imitatum Smith and Halictus ligatus Say (Hymenoptera: Halictidae) being the most abundant species collected, primarily in the yellow bowl pan traps at ground level.

Eastern hemlock, Tsuga canadensis (L.) Carriere, and Carolina hemlock, Tsuga caroliniana Engelmann, provide unique habitat that is threatened by the invasive hemlock woolly adelgid, Adelges tsugae Annand, which arrived in Georgia in 2003. In an attempt to conserve a portion of the mature hemlocks in north Georgia, the USDA Forest Service created over 100 Hemlock Conservation Areas throughout the Chattahoochee National Forest and designated them to receive chemical and/or biological control. Sasajiscymnus tsugae Sasaji and McClure, Laricobius nigrinus Fender, and Scymnus sinunodulus Yu and Yao are predatory beetles reared in the laboratory and released in these areas. To determine establishment of these predators, infested hemlock trees were sampled during spring 2010 - 2012 at some of these release sites. Additionally, nonrelease sites, 0.4 -1.6 km from release areas, were sampled in 2012 to evaluate predator spread from release trees. Five hundred ninety-two S. tsugae, 232 L. nigrinus, 262 nativ...

Warm season turf taxa of centipedegrass [Eremochloa ophiuroides (Munro) Hack], bermudagrass [Cynodon L.C. Rich, spp.], St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze], and zoysiagrass [Zoysia Willd. spp.] were evaluated for tolerance to adult twolined spittlebug (Prosapia bicincta Say) feeding in choice and no-choice experiments, and for their ability to support nymphal development (antibiosis potential). Among 133 selections evaluated, few showed evidence of potential antibiosis and/or improved tolerance over commercially available cultivars. Most of the centipedegrass taxa evaluated were susceptible to the spittlebug. However, some potential antibiosis among Chinese centipedegrass taxa was identified, and there was a gradient in the ability to tolerate spittlebug feeding. Among centipedegrasses, TC 358 and TC 362 showed moderate tolerance and recovery in no-choice and choice trials. The most tolerant bermudagrasses in no-choice trials were 00 - 23, 03 - 14, and 03 - 15. Centipedegra...

Twenty-one taxa of the warm-season perennial grass, Paspalum spp., were evaluated for response to the fall armyworm, Spodoptera frugiperda (J. E. Smith), an important pest of turfgrass. In studies using excised grass clippings conducted in a growth chamber and on whole plants in a greenhouse, the most resistant taxon was P. ionanthum Chase (PI 404,449) as measured by larval and pupal weights, days to develop to pupal stage, and survival. Paspalum notatum Fluegge var. saurae Parodi (PI 422,024), P. notatum Fluegge (PI 310,146), P. thunbergii Kunth ex Steud. (PI 286,486) and P. macrophyllum Kunth. (PI 282,807) showed moderate resistance, whereas the turf-type P. vaginatum Swartz taxa were highly susceptible. Identifying resistant Paspalum taxa can inform plant breeding programs in development of pest-resistant grasses, a foundational integrated pest management strategy.

The leafminer, Liriomyza trifolii (Burgess) is a key pest of gerbera daisies (Gerbera jamesonii Bolus), which are among the most preferred cut flowers in the world. While insecticides often fail to control this pest, parasitoids have proven to be effective. To maintain the parasitoids in the system, pesticide applications should be avoided. However, the influx of secondary pests like mites, thrips, whiteflies, and aphids during the growing season necessitates chemical sprays, which are effective in controlling the secondary pests, but are often toxic to the natural enemy and hence disrupt biological control. Since chemicals are not easily avoided in this system, an alternative method to avoid leafminers was sought, using host plant resistance, which can be an important component of integrated pest management (IPM) programs. Sixty gerbera cultivars were evaluated for potential resistance to L. trifolii. A range in susceptibility measured as leaf punctures and developing mines was evident for the first five weeks of a six-week exposure period. Gerberas ‘Jaguar Pink’, ‘Jaguar Rose Deep’, ‘Jaguar Salmon Pastel’, and ‘Revolution Spring Pastel’ were the least damaged, exhibiting less than 20% of the highest damage on at least two observation dates. However, consistent exposure to high numbers of leafminers resulted in similar expression of damage among all cultivars after five weeks. Differences among cultivars in force required to puncture leaves could not be consistently associated with damage due to leafminers

Pesticides commonly used in commercial greenhouse management were evaluated for compatibility with two biological control agents: a leafminer parasitoid (Diglyphus isaea [Walker]), and a predatory mite (Neoseiulus californicus [McGregor]). These natural enemies were exposed to miticides, fungicides, and insecticides targeting leafminers, thrips, and whiteflies, according to label directions in laboratory vial assays, after which mortality at 12, 24, and 48 h was recorded. Greater mortality of predatory mites than leafminer parasitoids was observed overall, illustrating that fewer pesticides were compatible with predatory mites compared with the parasitoid. However, some commonly used pesticides were found to cause high mortality to both the leafminer parasitoid and predatory mites. Twospotted spider mite (Tetranychus urticae Koch) infestations often disrupt leafminer (Liriomyza trifolii [Burgess]) biocontrol programs. Therefore, potentially compatible miticides (bifenazate, hexythiazox, spiromesifen, acequinocyl, etoxazole, and clofentezine) identified in laboratory trials were also evaluated in a greenhouse study and found to be compatible with leafminer biocontrol.

The squash bug, Anasa tristis (DeGeer) (Hemiptera: Coreidae), is an indigenous pest of squash and other cucurbits. Pesticides can control squash bug populations although many small-scale growers in the Southeast seek alternative methods of management. Cultural control methods, including varying the planting date and farmscaping, are not well understood under southeastern conditions. The goal of farmscaping is to increase natural ecosystem functions to aid in the control of pest populations. In the summers of 2014 and 2015, field plots of squash, separated by a minimum of 150 m were organized in a split-split plot design, with floral resources at the whole-plot level and varied planting date at the subplot level. Data were collected on squash bug abundance and fruit yield (kg), and abundance of potential natural enemies of A. tristis. Plots with added floral resources had fewer squash bug adults than plots without added floral resources in four of eight possible year × site × planting date combinations. Furthermore, the site in 2014 which had a reduction in squash bug adult abundance also had an increase in the abundance of potential enemies, including spiders, ground beetles, and predaceous Hemiptera. There were additional instances when potential natural enemy abundance was greater in resource-enhanced plots, but they were not associated with sites that had a reduction in yield loss or squash bug abundance. The use of floral resources to attract natural enemies and beneficial insects merits further investigation.

The lace bug, Leptodictya plana Heidemann, was sampled in the field on Pennisetum purpureum Schumach. from May through late October during 2008 and 2009. Highest population levels occurred in late August, which corresponded to the warmest temperatures of the season. Adults overwintered in ground litter/mulch and contributed eggs to as many as 4 overlapping generations in central Georgia, USA. Damage ratings on P. purpureum ornamental grasses averaged 20% for the entire 2008 and 2009 summer seasons, although individual plants expressed injury as high as 90% during midseason. When 2 ornamental grass standards were compared with each other, ‘Princess’ was more heavily damaged than ‘Prince’ during both sampling years. Decreased abundance observed in 2009 may have resulted from an increase in the amount of precipitation at the site. Mean duration of development ranged from 23.3 days at 30°C to 40.5 days at 25°C. Eggs hatched at 20, 25, 30 and 35°C, but not at 10 or 15°C. Complete development (egg to a...

We studied the distribution of hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), within hemlock trees for three summer (progrediens) and two winter (sistens) generations in northern Georgia. Eastern hemlock, Tsuga canadensis (L.) Carrière, trees were treated with 0, 10, or 25% of 1.5 g of imidacloprid per 2.5 cm of tree diameter at breast height and fertilized or not in a factorial design. Adelgid ovisacs per centimeter of branch were more abundant from June 2007 to June 2008 in the upper tree crown of insecticide untreated trees and when all trees were combined and that was the general trend for most comparisons. However, ovisacs were more abundant in the lower crown of insecticide treated trees in June 2008. More sistens nymphs settled on the upper crown branches than on the lower branches in summers 2007 and 2008. Higher eggs per ovisac were observed in the upper crown in February 2008 and in both the winter and summer 2009. In contrast, adelgids were more fecund in the lower crown in June 2008. On fertilized trees, eggs laid per adult were higher in the upper crown in February 2008. In summer 2008, eggs per ovisac were higher in the lower crown, but this reversed again to the upper crown by summer 2009. New growth of branches also varied among sample dates. These data demonstrate the variable distribution of adelgid and hemlock growth within trees over time and suggest that sampling only one crown area will not provide accurate estimates of adelgid densities.

'Tift 8' (Reg. No. CV-259, PI 659801) is a trispecific ornamental hybrid of Pennisetum approved for release by the University of Georgia College of Agricultural and Environmental Sciences in 2010. It was produced from crosses between P. purpureum Schumach; P. squamulatum Fresen.; and P. glaucum (L.) R. Br. This trispecific hybrid is both pollen and seed sterile. Tift 8 is a vegetatively propagated cultivar that is perennial in USDA hardiness zones 8-10. It can be grown as a vigorous annual in more northern zones. Tift 8 is morphologically similar to 'Tift 17', but it is significantly taller and has a significantly smaller culm-leaf angle than Tift 17. Tift 8 is significantly more resistant to Helminthosporium leaf spot (caused by Helminthosporium ocel/um Faris) than 'Princess'. Mature leaves of Tift 8 have a reddish-purple color. The plant color of Tift 8 is equal to, and in some tests better than, that of Tift 17. Tift 8 flowers under short days; therefore, it will not produce inflorescences where winter temperatures reach freezing (O°C) or below, or before the daylength is 10.5 h. A plant patent application has been submitted for Tift 8.

Leptodictya plana Heidemann is an emerging pest on ornamental grasses in the southern United States. Thirty-two selections of commercially available ornamental grasses and sedges and five trial accessions of Pennisetum purpureum were evaluated for susceptibility to L. plana feeding and oviposition. No-choice studies were conducted in a greenhouse by securing four lace bugs to leaf blades of each plant using clip cages. Lace bugs stayed attached for five days. Damage and number eggs were recorded. Choice studies were conducted in the laboratory by placing leaf blades from each genus of plant species into a large petri dish in a spoke pattern. There were no plants tested that consistently received zero percent damage in either trial. Plants that sustained the least damage included Acorus spp., Cordyline spp., and Panicum spp. Pennisetum spp. entries exhibited the highest overall percent damage and were the only genera of plants that supported oviposition.

The influence of turfgrass genotype (bermudagrass, Cynodon dactylon (L.), centipedegrass Eremochloa ophiuroides Munro Hack, St. Augustinegrass Stenotaphrum secundatum [Walt.] Kuntze, zoysiagrass, Zoysia spp., and tall fescue, Festuca arundinacea Schreb) on occurrence of hymenopteran parasitoids was evaluated in residential turf during May, June and July in 2005. Most wasps belonged to Chalcidoidea (55%) and Platygastroidea (29%). Adult wasps representing Mymaridae, Platygastridae, Scelionidae and Braconidae were captured in all turfgrasses. Among all wasps, 26.5% were mymarids and included Gonatocerus sp. and Mymar sp. Eulophidae, Aprostocetus and Pnigalio sp. were less abundant in centipedegrass compared with other turfgrasses. Trichogrammatids (18.2% of total wasps) were more abundant in St. Augustinegrass or tall fescue than in zoysiagrass. Platygastrid wasps, Allotropa and Fidiobia sp., were most often collected from zoysiagrass and St. Augustinegrass. Scelionids represented 23% of the total parasitoi...

Predatory potential and performance of the predaceous heteropterans, Geocoris punctipes (Say), G. uliginosus (Say) (Geocoridae), and Onus insidiosus (Say) (Anthocoridae), were evaluated using fall army worm, Spodoptera frugiperda (J. E. Smith), as prey on different turfgrass taxa (resistant zoysiagrasses, ‘Cavalier’ and ‘Palisades’; moderately resistant Bermuda grass, ‘TifSport’; and susceptible seashore paspalum, ‘Sea Isle 1’) through laboratory and field studies. When background mortality was taken into account, in small arena trials in the laboratory, the greatest mortality by predators occurred on TifSport. The predator impact on TifSport by O. insidiosus was 92.6% above the mortality in the no-predator treatment on that grass. Predator induced mortality was rarely significant on the highly resistant zoysiagrass cultivar Cavalier because mortality, even in the absence of predators, was so high. Survival of larvae on TifSport Bermuda grass was significantly reduced by the addition of just two ...

The effect of taxa [common Bermuda grass, Cynodon dactylon (L.); centipedegrass, Eremochloa ophiuroides Munro Hack; St. Augustinegrass, Stenotaphrum secundatum [Walt.] Kuntze; and zoysiagrass, Zoysia spp.], density, height, and weed density on abundance of natural enemies, and their potential prey were evaluated in residential turf. Total predatory Heteroptera were most abundant in St. Augustinegrass and zoysiagrass and included Anthocoridae, Lasiochilidae, Geocoridae, and Miridae. Anthocoridae and Lasiochilidae were most common in St. Augustinegrass, and their abundance correlated positively with species of Blissidae and Delphacidae. Chinch bugs were present in all turf taxa, but were 23-47 times more abundant in St. Augustinegrass. Anthocorids/lasiochilids were more numerous on taller grasses, as were Blissidae, Delphacidae, Cicadellidae, and Cercopidae. Geocoridae and Miridae were most common in zoysiagrass and were collected in higher numbers with increasing weed density. However, no predatory Heteroptera were affected by grass density. Other beneficial insects such as staphylinids and parasitic Hymenoptera were captured most often in St. Augustinegrass and zoysiagrass. These differences in abundance could be in response to primary or alternate prey, or reflect the influence of turf microenvironmental characteristics. In this study, Simpson's diversity index for predatory Heteroptera showed the greatest diversity and evenness in centipedegrass, whereas the herbivores and detritivores were most diverse in St. Augustinegrass lawns. These results demonstrate the complex role of plant taxa in structuring arthropod communities in turf. An increased understanding of how turf species and cultivars help shape pest and beneficial arthropod communities will enhance predictive abilities and further pest management objectives.

Prosapia bicincta (Say) (Hemiptera: Cercopidae), the twolined spittlebug, is an economic pest of turfgrass in the southeastern United States. No data concerning natural enemies of P. bicincta in turfgrass have been reported previously. We compared predation of spittlebug eggs, nymphs, and adults in the laboratory by potential generalist predators commonly found in turfgrass: bigeyed bugs Geocoris uliginosus Say and Geocoris punctipes Say; red imported fire ant, Solenopsis invicta Buren; wolf spiders (Lycosa sp. Walckenaer); carabid beetles Harpalaus pensylvanicus DeGeer and Calosoma sayi Dejean; and tiger beetles Megacephala carolina carolina L. Eggs were readily consumed by generalist predators. S. invicta consumed 100% of the eggs offered. H. pensylvanicus and C. sayi were also significant predators of P. bicincta eggs. Nymphs live in spittlemasses that protect them from attack by predators, but exposed nymphs were susceptible to attack when mechanically removed from their spittlemasses. S. invicta and M. carolina carolina caused significant mortality of exposed nymphs. P. bicincta adults are aposematic and have the ability to reflex bleed; however, reflex bleeding did not prevent attack by predators. S. invicta and M. carolina carolina killed 100% of the adult spittlebugs offered in laboratory bioassays. Lycosa sp. are less voracious predators of adults. Sound background knowledge about P. bicincta and its potential natural enemy complex is important for the development and implementation of a detailed, site-specific, biologically based pest management program in turfgrass.

The functional response of the tiger beetle Megacephala carolina carolina L. (Coleoptera: Carabidae) was determined on adult twolined spittlebug, Prosapia bicincta (Say) (Hemiptera: Cercopidae), and fourth instars of fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), in single-prey and two-prey systems. In the laboratory, M. carolina carolina demonstrated a type II functional response for P. bicincta and S. frugiperda in both single- and two-prey systems. Search efficiency of M. carolina declined for both prey as the initial number of prey increased. Of the total prey consumed, M. carolina carolina killed significantly more S. frugiperda than P. bicincta in the single-prey system (8.0 and 4.5, respectively) and the two-prey system (5.0 and 2.0, respectively). Estimates of attack coefficient, a, were not significantly different for P. bicincta and S. frugiperda in the single-prey (0.07 and 0.02) and two-prey systems (0.04 and 0.06), respectively. The handling time, T(h), was significantly greater for P. bicincta (5.02 and 10.64 h) than for S. frugiperda (2.66 and 4.41 h) in single- and two-prey systems, respectively. Estimations of attack coefficient and handling time in the single-prey system were used to predict prey preference of M. carolina carolina. No strong prey switching response was observed. M. carolina carolina showed no preference for either prey. However, in the presence of S. frugiperda, the functional response of the predator for P. bicincta was reduced. M. carolina carolina is a potential predator of one or more turfgrass pests and should be considered in conservation efforts.

Columbine, Aquilegia spp., are regularly attacked by agromyzid leafminers, Phytomyza spp. Effects of columbine species and cultivars on infestation by the leafminer Phytomyza aquilegivora Spencer, and subsequent parasitism by hymenopterous parasitoids was evaluated in two-year field trials at four locations in central and north Georgia. Among 20 columbine taxa planted in non-irrigated, wooded sites in central and north Georgia, two selections (A. flabellata and A. caerulea ‘Dwarf Fantasy Mix’) were comparable to the moderately resistant native species A. canadensis. In irrigated sites in central and north Georgia, all cultivars were equally infested by the leaf miner. The most heavily attacked selections among all sites were A. alpina, A. chrysantha ‘Yellow Star’, A. caerulea, A. caerulea ‘McKana mix’, A. caerulea ‘Music hybrid’, A. skinneri, and A. x hybrida ‘Ruby Port’. The variegated selection, A. vervaeneana ‘Woodside’, sustained intermediate infestation levels as did A. vulgaris ‘Winkie Blue & White’. Cultivar influences on parasitism of leafminers was quantified at two sites. Eleven species of hymenopteran parasitoids representing three families were recovered. Leafminers infesting A. chrysantha ‘Yellow Star’ were most heavily parasitized at both locations. Chrysocharis pentheus Walker was the most abundant parasitoid, representing 41% of all parasitoids collected and 48.4% of the species reared from leafminers in central Georgia. Seladerma sp. was the only parasitoid reared from leafminers collected in north Georgia and represented 22.1% of all parasitoids obtained.

Interactions between host plant resistance and biological control may beneÞt or hinder pest management efforts. Turfgrass cultivars have rarely been tested for extrinsic resistance charac- teristics such as occurrence and performance of beneÞcial arthropods on plant genotypes with resistance to known turf pests. Parasitism of fall armyworm,Spodopterafrugiperda (J.E. Smith), among six turfgrass genotypes was evaluated. The six grasses tested (Sea Isle-1 and 561-79 seashore paspalum, Paspalum vaginatum Swartz; TifSport and TifEagle hybrid Bermuda grass, Cynodon dactylon (L.) C.transvaalensis (Burtt-Davy); and Cavalier and Palisades zoysiagrass,Zoysiajaponica von Steudel and Z. matrella (L.) Merrill, respectively) represented a range in resistance to S. frugiperda. Differential recovery of larvae released as Þrst instars resected this gradient in resistance of Cavalier Palisades TifSport TifEagle 561- Sea Isle-1 Larval recovery (percentage of initial number released) was greatest in May, less in July and August, and least in October, probably resecting the increase in activity of on-site predators and disease pressure. Parasitism of the fall armyworm by the braconid Aleiodes laphygmae Viereck varied among turfgrass genotypes. Parasitism was greatest during July. In total, 20,400 Þrst instars were placed in the Þeld; 2,368 were recovered; 468 parasitoids were subsequently reared; 92.2% were A. laphygmae. In the Þeld, the greatest percentage of reduction in S. frugiperda larvae by A. laphygmae occurred on the armyworm-susceptible seashore paspalums (51.9% on Sea Isle-1 in July). Cotesia marginiventris Cresson and Meteorus sp. also were reared from collected larvae. No parasitoids were reared from larvae collected from resistant Cavalier zoysiagrass.A.laphygmae and C. marginiventris were reared from larvae collected from the other Þve grass cultivars. No parasitoids of older larvae or pupae were observed.

The residual activity of six concentrations of chlorpyrifos, spinosad, and halofenozide on fall armyworm, Spodoptera frugiperda (J. E. Smith), as mediated by five warm-season turfgrass cultivars expressing varying levels of genetic resistance was evaluated in greenhouse trials. Similarly, varying concentrations of halofenozide were applied to six turfgrass cultivars in the field; mortality of neonate and third-instar fall armyworms was assessed. Reduced rates of chlorpyrifos resulted in lower fall armyworm survival on resistant zoysiagrass cultivars relative to that on bermudagrass or paspalum. In a separate trial when treated with spinosad, survival on the same zoysiagrasses was equal to or greater than that on more susceptible bermuda or paspalum. Reduced rates of halofenozide in another greenhouse trial resulted in lower survival on resistant zoysiagrasses at some concentrations at 7, but not at 14, days exposure compared to more susceptible grasses. In the field, at the full labeled rate of halofenozide, 100% mortality was observed regardless of turfgrass cultivar. Larval survival on the most susceptible turf, “TifEagle”, was higher than that on the remaining turf cultivars at the intermediate rate applied. Larvae exposed to treated turf as third instars displayed a trend toward greater survival at intermediate rates on the two paspalums, “Sea Isle 1” and 561-79, while a trend toward lower survival was observed on “Palisades” and “Cavalier” zoysiagrasses. Factors potentially contributing to the variation in responses observed in the present study include different modes of action of insecticides, host plant resistance mechanisms, differential foliar consumption rates and insecticide dose in relation to body weight. Development of management guidelines for pest management practitioners must address the complexity of potential interactions and may require “case by case” evaluation.

Proper timing of pesticide applications is paramount when attempting to control scale insects (Hemiptera: Diaspididae, Coccidae) that are important pests of landscape plantings. Use of degree-days and phenological indicators can better time the applications and reduce the number of treatments. Seasonal appearance of five species of scale insects in the urban landscape along with flowering phenology of 40 plant species were systematically monitored during 1997, 1998, 1999 and 2000 in Athens, GA. Degree-day calculations for predicting first-generation crawler emergence were attained by two methods: use of standard-base or an experimentally determined base temperature. Predictions using a standard temperature resulted in high year-to-year variance. Use of a model-derived base temperature reduced the variance for degree-days needed for first crawler emergence. Mean base temperatures for European fruit lecanium, Indian wax scale, obscure scale, euonymus scale, and tea scale were, respectively, 12.78, 12.78, 5.0, 3.89, and 5.0°C. The range in degree-days required for first crawler emergence of each species using first the experimentally derived base, or the standard base temperature of 10.56 were 1184 to 1296 or 1064 to 1622 for European fruit lecanium; 846 to 1014 or 1150 to 1380 for Indian wax scale; 1246 to 1268 or 515 to 566 for obscure scale; 1366 to 1492 or 313 to 597 for euonymus scale; and 526 to 1502 or 202 to 776 for tea scale. Natural enemy complexes observed in association with each of the scale species are discussed.

Interactions between host plant resistance and biological control may be advantageous or disadvantageous for pest management. Turfgrass cultivars have rarely been tested for extrinsic resistance characteristics such as occurrence and performance of beneÞcial arthropods on plants with resistance to known turf pests. Among six turfgrass cultivars tested, the bigeyed bug, Geocorisuliginosus (Say) nymphs varied in ability to reduce numbers of fall armyworm, Spodoptera frugiperda (J. E. Smith), larvae. The six grasses tested (Sea Isle 1 and 561-79 seashore paspalum, Paspalum vaginatum Swartz; TifSport and TifEagle bermudagrass, Cynodon dactylon (L.) x C. transvaalensis (Burtt-Davy); and Cavalier and Palisades zoysiagrass Zoysia japonica von Steudel and Z. matrella (L.) Merrill) represented a range in resistance to S. frugiperda. In the laboratory, the greatest reduction in S. frugiperda larvae by a low density of G. uliginosus occurred on the resistant Cavalier zoysiagrass. A 7-fold difference in weight of 10-d-old larvae between those feeding on susceptible versus resistant grasses suggested that on the resistant grass larvae remained for a longer period in a size range susceptible to predation. Results of laboratory studies were not directly translated to the Þeld, in which a diverse predatory arthropod community varied in composition depending on turfgras cultivar. In the Þeld, the greatest reduction in S. frugiperda larvae by a low density of G. uliginosus occurred on Sea Isle 1 and 561-79 seashore paspalum grass. In the Þeld, vacuum samples indicated that predaceous Heteroptera were most abundant in paspalum grasses and bermudagrasses, while Carabidae, Staphylinidae, and Araneae were more common in zoysiagrasses. In contrast, pitfall traps indicated that carabids were more common in bermudagrasses, Araneae and Staphylinids were similar among grass taxa, and Cicindellidae were most common in paspalum grasses and bermudagrasses. Predation was never signiÞcantly decreased on resistant turfgrass cultivars in any of the experiments described in this work, indicating no negative tritrophic interactions.

Pyramid-shaped traps were evaluated in Georgia for capturing potentially harmful coleopterans in ornamental plant nurseries. Beetle response to two colors and four bait types was compared. Four species of Buprestidae, 22 species of Cerambycidae, and three species of Curculionidae were captured in sufficient numbers for analysis during the 2-yr study. Coccinellidae, Carabidae, Trogositidae, Cleridae, and Chrysomelidae were also captured with frequency. Trap color did not have a significant effect on capture of pine-infesting weevils, although these weevil species were as much as five times more abundant in traps containing turpentine alone or a 1:1 mixture of turpentine: ethanol than ethanol alone or unbaited traps. Odontopus calceatus (Say), however, a weevil that attacks the foliage of tuliptree, sassafras and magnolia, was captured five times more frequently in yellow than in gray traps, although no influence of bait was observed for this species. Cerambycidae in general were not affected by trap color or bait. However, the banded hickory borer, Knulliana cincta (Drury), a cerambycid, was captured more frequently in gray traps as were buprestids in the genus Chrysobothris. Buprestis lineata was more commonly captured in traps baited with turpentine or ethanol/turpentine mixture. Chrysomelids (Altica sp.) were not affected by trap color or bait type. Timing of occurrence of adult beetles of 23 species of beetles are presented. The beneficial Coleoptera captured in the traps were either not affected by color or bait type (Carabidae) or were primarily attracted by yellow traps (Coccinellidae). Traps of the type used in this study can be easily constructed or may be purchased commercially and offer the nursery grower a practical monitoring tool for a variety of Coleoptera that attack woody plants.

Conservation and augmentation of indigenous natural enemies are promising strategies for biologically based pest management in outdoor urban environments. This research sought to determine whether the addition of wildflower plantings would enhance the occurrence, abundance and impact of beneficial arthropods in the landscape, and to determine the potential compatibility of pest-resistant turfgrass and natural control of Japanese beetle, Popillia japonica Newman, and fall armyworm, Spodoptera frugiperda (J.E. Smith). A bermudagrass cultivar (susceptible to fall armyworm), a zoysiagrass cultivar (resistant to fall armyworm), and two different commercially available wildflower mixes all harbored a diverse array of beneficial arthropods in both large and small plot evaluations. A wildflower mix containing 15 species of flowers provided significant, season-long increases in foliar-dwelling spiders and bigeyed bugs during 1-yr of a 2-yr study in large (1,512 m2) plots. Ground-dwelling spiders were more...

The effects of azalea lace bug, Stephanitis pyrioides (Scott), feeding injury on azalea growth and development were investigated using 'Girard's Rose' azaleas during a 2-yr field study in Georgia Low, medium, and high injury treatments, which corresponded to 6, 8, and 14% maximum canopy area injury, were compared with control azaleas that received no lace bug infestation. Flower number, whole-shrub leaf and stem dry mass, and dry mass and size of new growth tissues were unaffected by treatments. In contrast, growth index measurements, a general measure of variability frequently used for horticultural differentiation, showed significant reductions for all treatments in comparison to control azaleas after 20 wk. Though not directly quantified, this apparent discrepancy may be explained as an artifact of lace bug feeding-induced leaf abscission. Growth index measurements had considerable variability and may not be the most reliable measurement of size. In July 1998, plant canopy densities among azaleas maintained in the high injury treatments were approximately 15% less full than the canopies of control shrubs. Predaceous insects had a significant negative association with azalea lace bug number during the 2-yr study. Flower and new tissue production, measured destructively during two growing seasons, revealed azalea tolerance to 14% of maximum canopy area lace bug feeding-injury levels.

Intensity and type of management, the cultural variable shade, and the combination of woody and herbaceous annual and perennial plants were evaluated for their effect on key landscape arthropod pests. Azalea lace bugs, Stephanitis pyrioides (Scott), and twolined spittlebugs, Prosapia bicincta (Say), were most effectively suppressed in landscape designed with resistant plant species of woody ornamentals and turf. Landscapes containing susceptible plant counterparts were heavily infested by these two insect species in untreated control plots. A traditional management program of prescribed herbicide, insecticide, and fungicide applications effectively suppressed azalea lace bug and produced a high-quality landscape. Targeted integrated pest management with solely horticultural oils resulted in intermediate levels of azalea lace bug. Neither program completely controlled twolined spittlebug on hollies or turf. Carabidae, Staphylinidae, Formicidae, and Araneae were not reduced by any management strategy. Lace bugs (Stephanitis) were more common in plots with 50% shade than those in full sun. Spittlebugs (Prosapia) were more common in the shade during 1996 and in the sun during 1997. Spiders and ants were more often collected in full sun plots. Carabids, staphylinids, and spiders were more commonly collected from pitfall traps in turf than in wood-chip mulched plant beds, whereas ants were equally common in both locations. The addition of herbaceous plants to the landscape beds had little effect on pest insect abundance.

Bermudagrass (Cynodon sp.) and paspalum (Paspalum vaginatum) genotypes were evaluated in laboratory, greenhouse, and field experiments for potential resistance to the common turfgrass pests, tawny mole cricket (Scapteriscus vicinus Scudder) and southern mole cricket (Scapteriscus borellii Giglio-tos). Potential resistance among 21 seashore paspalums to both insects in an environmental chamber at 27 °C, 85% relative humidity, and 15 hours light/9 hours dark) revealed that Glenn Oaks `Adalayd' was least tolerant of cricket injury, while 561-79, HI-1, and `Excalibur' were most tolerant. Nymphal survival was not influenced by turfgrass type. Plant selections that maintained the highest percentage of their normal growth after 4 weeks of feeding by tawny mole crickets over three separate greenhouse trials were 561-79, HI-1, HI-2, PI-509018, `Excalibur', SIPV-1 paspalums, and `Tifeagle' and `Tifsport' bermudagrasses. Although none of the tested genotypes was highly resistant to tawny mole cricket injury, `TifSport' bermudagrass and 561-79 (Argentine) seashore paspalum were most tolerant.

A comparison of whole-plant and individual-leaf gas exchange measurements was undertaken among azaleas, Rhododendron spp., treated with insecticides used to control the azalea lace bug, Stephanitis pyrioides (Scott). Azaleas in individual-leaf trials received 3 insecticide treatments during three 21-day trials. The whole-plant study included 2 insecticide treatments and was conducted during a 21-day trial. Individual-leaf studies indicated that insecticidal soap and acephate application at higher than recommended rates caused short-term reductions in gas exchange. However, variability among individual-leaf measurements prevented consistent conclusions. Whole-plant gas exchange measurements provided consistent results and confirmed that insectidical soap caused short-term reductions in P net and R dark . Additionally, whole-plant gas exchange measurements enabled growth analyses and demonstrated a reduction in carbon use efficiency attributed to insecticidal soap treatments. Neither acephate nor horticultural oil significantly affected whole-plant gas exchange. Gas exchange parameters for treatments in all trials were not significantly different from the controls by Day 21.

Questionnaires on pesticide use and other aspects of integrated pest management (IPM) were mailed to 1678 lawn care and landscape maintenance firms in the 20 county metropolitan Atlanta area. The survey return rate adjusted for nonapplicable addresses and undeliverable mailings was 25.4%, yielding a total of 350 usable surveys. Responding lawn care and landscape maintenance professionals purchased a total active ingredient of 250,527 lb (93,447 kg) of herbicide, 35,416 lb (13,210 kg) of insecticide and 10,367 lb (3,867 kg) of fungicide during 1993. Most insecticides and fungicides were applied during June, July, and August. About one-third of herbicides were applied during March to May, one-third during June to August, and one-third during September to February. Key pests and plants were identified by survey respondents. Opportunities and impediments to implementation of IPM in the landscape as reported by respondents are discussed.

Lawn care and landscape maintenance (LCLM) firms in the Atlanta metro area were surveyed to determine industry pest management practices. Factor analysis is used to determine pest management systems in the LCLM industry. Primary factors include preventive applications, chemical intensive management, growth regulators and traps, beneficial insects, and bio-intensive management. Independently owned and small firms tend to have lower degrees of adoption of integrated pest management (IPM) factors than corporate and large firms. Comparison of pest management factors in the LCLM industry with those in agriculture suggest that similar IPM systems exist in both industries.

Feeding injury caused by nymphs, males and females of the azalea lace bug, Stephanitis pyrioides (Scott), reduced rates of photosynthesis and transpiration in ‘Delaware Valley White’ azalea, Rhododendron mucronatum leaves. Females caused substantially more leaf feeding injury than males or nymphs. S. pyrioides was observed to insert stylets through stomata on the lower leaf surface and to feed almost entirely on upper palisade parenchyma tissue by piercing and removing cell contents. Lace bug feeding increased leaf stomatal resistance which indicated that gas exchange was restricted by stomatal closure. Feeding injury also reduced leaf chlorophyll content and photosynthetic capacity of remaining chlorophyll, but did not consistently affect chlorophyll a:b or specific leaf weight. Net leaf photosynthesis was negatively correlated with stomatal resistance and positively correlated with both chlorophyll content per unit leaf area and photosynthetic rate of remaining chlorophyll. These results indicated that S. pyrioides reduced leaf photosynthesis in azalea by damaging palisade parenchyma which restricted gas exchange through stomata and reduced leaf chlorophyll content and photosynthetic capacity of remaining chlorophyll.

Thrips inhabiting leaf galls on noncultivated Vaccinium species were surveyed throughout Georgia. Frankliniella caudiseta Sakimura & O'Neill was present on V. tenellum Aiton, and V. myrsinites Lam. Blueberry thrips, Frankliniella vaccinii Morgan, was only collected from V. arboreum Marsh. Catinathrips similis Nakahara occurred on V. tenellum and V. myrsinites . However, C. vaccinicola Nakahara was collected only on V. arboreum. Haplothrips rectipennis Hood, a predaceous species, was found on all Vacciniurn species. F. vaccinii and C. vaccinicola were both capable of initiating gall formation on plants in the spring. Both species may coexist in the same gall and are univoltine on mature growth during a season. However, in cutover areas where new plant growth was generated during the summer, 1 additional generation was produced. Adult terebrantians became active during April. Larvae were abundant during May and June. On 2nd-growth plants, larvae were abundant during July and August and adults were collected in October. The predator H. rectipennis colonized galls during May. Larvae of this species became abundant during May and June. One generation was produced. Adults remained in the galls until leaves dropped from the plants, usually in October. Thrips significantly reduced shootlength, bud formation, and fruit production of both V. arboreurn and V. myrsinites . These observations have implications for blueberry plant improvement efforts.

Healthy hemlock trees, Tsuga canadensis (L.) Carriere, and hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), populations should favor retention and population growth of adelgid predators such as Laricobius nigrinus Fender (Coleoptera: Derodontidae) and Sasajiscymnus tsugae (Sasaji & McClure) (Coleoptera: Coccinellidae). Eastern hemlock trees between 15 and 38 cm diameter at breast height (dbh) were treated with 0, 10, or 25% of 1.5 g imidacloprid (Merit 75 WP) per 2.5 cm dbh and were either fertilized or not, in a 3 by 2 factorial design. After 2 yr, imidacloprid reduced the numbers of ovisacs and eggs found on trees in a dosage-dependent manner, while enhancing tree growth parameters such as new shoots or needles and the length of new shoots. Fertilized trees had greater adelgid fecundity, which was positively correlated with total foliar N in both winter generations. In February 2009 (27 mo after imidacloprid treatment), higher imidacloprid dosages to unfertilized trees resulted in reduced adelgid fecundity. Concentrations of N, P, and K were higher in the foliage of trees treated with insecticide, whereas foliar aluminum concentrations were consistently lower in trees with higher insecticide dosages. Trees treated with low rates of imidacloprid were healthier than untreated trees, but only trees treated with the 0.1× dosage had sufficient adelgids to possibly sustain predators over extended periods.

Understanding how fertilization affects host resistance to hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), is important because fertilizers are often used to grow resistant selections to a suitable size for testing. We evaluated four hemlock species (Tsuga) under three different fertilizer regimes to assess whether fertility affected resistance to the adelgid and to determine whether it affected feeding preferences of the adelgid predators Laricobius nigrinus Fender and Sasajiscymnus tsugae (Sasaji & McClure). Treatments were long-term fertilization (from June 2008 to June 2009), short-term fertilization (from March to June 2009), and no fertilizer. Fertilizer was applied biweekly with 240 ppm N by using water-soluble fertilizer (N-P-K, 20:20:20). Plants (>1 yr old) were artificially infested with adelgids on 31 March 2009. Among unfertilized hemlocks (n=10 per species), foliar N was highest in Tsuga mertensiana (Bong.) CarriBre and lowest in T. chinensis (Franch.) E. Pritz. Significantly more progredien ovisacs or sisten eggs were present on T. mertensiana than on the other hemlock species with none on unfertilized T. chinensis. A. tsugae adults on T. heterophylla (Raf.) Sarg. were unaffected by fertility, but densities of developing A. tsugae nymphs were higher on unfertilized T. heterophylla plants than on fertilized T. heterophylla plants regardless of fertilizer treatment. Both L. nigrinus and S. tsugae consumed more adelgid eggs that developed on fertilized T. canadensis than from unfertilized plants. The predators did not exhibit this preference for adelgid eggs from females that developed on T. heterophylla or T. mertensiana.

Turfgrass selections including 21 paspalums (Paspalum vaginatum Swartz) and 12 zoysiagrasses (Zoysia sp.) were compared with susceptible `KY31' tall fescue (Festuca arundinacea Schreb.) and more resistant common bermudagrass (Cynodon dactylon Pers.) and common centipedegrass [Eremochloa ophiuroides (Munro.) Hack] for potential resistance to fall armyworm [Spodoptera frugiperda (J.E. Smith)], an occasionally serious pest of managed turf. Turfgrass and pasture grasses annually suffer sporadic damage by this pest, often severe in the Gulf Coast states. Resistant grasses offer an alternative management tool for the fall armyworm, reducing the need for pesticide use. Laboratory evaluations assessed the degree of antibiosis and nonpreference present among more than 30 turfgrass genotypes to first and third instar fall armyworms, respectively. Zoysiagrasses exhibiting high levels of antibiosis included `Cavalier', `Emerald', DALZ8501, DALZ8508, `Royal', and `Palisades'. Paspalum selections demonstrating reduced larval or pupal weights or prolonged development times of fall armyworm included 561-79, Temple-2, PI-509021, and PI-509022.

Predatory potential and performance of the predaceous heteropterans, Geocoris punctipes (Say), G. uliginosus (Say) (Geocoridae), and Orius insidiosus (Say) (Anthocoridae), were evaluated using fall armyworm, Spodoptera frugiperda (J. E. Smith), as prey on different turfgrass taxa (resistant zoysiagrasses, 'Cavalier' and 'Palisades'; moderately resistant Bermuda grass, 'TifSport'; and susceptible seashore paspalum, 'Sea Isle 1') through laboratory and field studies. When background mortality was taken into account, in small arena trials in the laboratory, the greatest mortality by predators occurred on TifSport. The predator impact on TifSport by O. insidiosus was 92.6% above the mortality in the no-predator treatment on that grass. Predator induced mortality was rarely significant on the highly resistant zoysiagrass cultivar Cavalier because mortality, even in the absence of predators, was so high. Survival of larvae on TifSport Bermuda grass was significantly reduced by the addition of just two O. insidiosus per pot in laboratory pot trials. An increase in predator density to 4, 6, 8, or 10 further suppressed larval survival. O. insidiosus reduced larval survival on Sea Isle 1 at all densities. On Sea Isle 1, a density of two O. insidiosus resulted in50% reduction in live fall armyworms compared with the no predator treatment in laboratory trials. However, addition of O. insidiosus did not significantly reduce survival of fall armyworm larvae on this cultivar in the field in the presence of alternative prey and predators. O. insidiosus densities of six or higher per 181.4 cm2 did significantly reduce larval survival on TifSport Bermuda grass by as much as 80% during a 5-d trial period in the field. Predator-induced mortality among all trials was most consistent on a grass of intermediate resistance, TifSport Bermuda grass.

Cotesia marginiventris (Cresson), Diolcogaster facetosa (Weed), and Rogas nolophanae Ashmead, which respectively parasitize progressively older green cloverworm, Plathypena scabra (F.) larvae, produced (x ± SE) 362.7 ± 24.1, 83.2 ± 11.4, 66.3 ± 6.1 offspring, respectively, during their lifetimes. Adult female longevity at 24°C averaged lS.l ± O.S, ~3.0 ± 0.9, and 29.9 ± 2.7 d for these species, respectively. Numbers of mature eggs from dissections of 2-d-old females were 105 ± 7.1,57 ± 5.9, and 5.2 ± 0.9. Primary braconid and tachinid parasitoids of the green cloverworm exhibited decreasing observed or estimated fecundities with respect to increasing age of host larvae attacked. Decreasing fecundities of these parasitoid species may reflect increasing potential for survival until time of parasitoid emergence of the progressively older host larvae which these species attack. Other factors suggested as influencing fecundity are breadth of host range and complexity of host location, capture, and oviposition behaviors.

The critical photoperiod for diapause induction was determined in the laboratory and validated in the field for Diolcogaster facetosa (Weed), a parasite of the green cloverworm. In the laboratory at constant 24°C, as well as in the field under natural conditions, the critical photoperiod for diapause induction is between 13:11 and 14:10 (L:D). Second instars are sensitive to diapause-inducing photoperiods, and diapause occurs in the final instar after it has emerged from the host and spun a cocoon. Study of diapausing individuals from the field during autumn and winter indicated that photoperiod has only a minor role, if any, in diapause maintenance or termination. The date of diapause termination was not determined, but the combination of diapause development and postdiapause development had not been completed in the field by the spring equinox.

The seasonal abundance and phenology of three Nabis species and their parasitoids were studied in alfalfa (Medicago sativa L.) and soybean (Glycine max (L.) Merrill). Although all three species were present in both crops, differences were noted in composition of the Nabis complex between the two systems. Nabis americoferus (Carayon) was numerically dominant in alfalfa, a crop in which this species produced three generations per year in central Kentucky. In soybean. where one generation is produced, N. roseipennis Reuter rather than N. americo/eros or N. rufusculus Reuter produced the greatest number of nymphs for the three consecutive years of study. Sweep sampling recovered fewer nymphal nabids in comparison with suction or shake sampling and, thus, was less satisfactory in assessing population trends. Parasitoids reared from nabids that had been collected as adults or nymphs in alfalfa or soybean included the tachinid Leucostoma simplex (Fallen) and the braconid Wesmaelia pendula Foerster. Parasitism by the mymarid egg parasitoid Polynema boreum Girault was much higher in alfalfa than in soybean (50% versus 5%).