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Root-feeding grubs (Coleoptera: Scarabaeidae) were sampled from damaged areas of 61 irrigated roughs on 32 Kentucky golf courses to determine species composition and natural enemy incidence, the first such survey in the United States' transitional turfgrass climatic zone. Masked chafers (Cyclocephala lurida Bland and C. borealis Arrow) and Japanese beetle (Popillia japonica Newman) accounted for ≈73 and 26% of grubs found in an autumn survey, with Cyclocephala spp. predominating at most sites, although mixed infestations were common. Only a few Phyllophaga spp., and no exotic species other than P. japonica were found. Cyclocephala spp. also predominated in seasonal and statewide surveys regardless of whether a course had cool- or warm-season grass fairways. Pathogenic bacteria, Paenibacillus and Serratia spp., and the autumn-active parasitoid Tiphia pygidialis Allen were the main enemies associated with Cyclocephala spp. Predominant enemies of P. japonica were Paenibacillus, Serratia, and Metarhizium spp. in autumn, and eugregarines, Stictospora sp. (probably S. villani Hays and Clopton) and Tiphia vernalis Rohwer in spring. Entomopathogenic nematodes and the microsporidian Ovavesicula popilliae Andreadis & Hanula were nearly absent in our samples. No predictive relationships were found between soil parameters and proportionate abundance of Cyclocephala or P. japonica, or with natural enemy incidence at particular sites. Although incidence of individual enemies was generally low (

The Japanese beetle, Popillia japonica Newman, has an unusually broad host range among deciduous woody plants, yet it feeds only sparingly, or not at all, on certain species in the field. We evaluated beetles' preference, survival over time and fecundity on eight woody plant species historically rated as susceptible or resistant and, after verifying those ratings, tested whether resistance is correlated with so-called quantitative defense traits including leaf toughness, low nutrient content (water, nitrogen, and sugars), and relatively high amounts of tannins or saponins, traditionally associated with such plants. We further tested whether species unsuitable for Japanese beetles are also rejected by fall webworms, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), the expected outcome if the aforementioned traits serve as broad-based defenses against generalists. Choice tests supported historical resistance ratings for the selected species: tuliptree, lilac, dogwood, and Bradford callery pear were rejected by Japanese beetles, whereas sassafras, cherry plum, Virginia creeper, and littleleaf linden were readily eaten. Rejected species also were unsuitable for survival over time, or egg-laying, indicating beetles' inability to overcome the resistance factors through habituation, compensatory feeding, or detoxification. None of the aforementioned leaf traits was consistently higher or lower in the resistant or susceptible plants, and plant species rejected by Japanese beetles often were not rejected by fall webworms. Specialized secondary chemistry, not quantitative defenses, likely determines the Japanese beetle's dietary range among deciduous woody plant species it may encounter.

We investigated the biology of Tiphia pygidialis Allen, a previously unstudied native parasitoid of masked chafer, Cyclocephala spp. grubs, in central Kentucky and the seasonal dynamics of Tiphia vernalis Rohwer, an introduced parasitoid of Japanese beetle, Popillia japonica Newman. T. pygidialis was active from mid-August to early October, parasitizing third-instar masked chafers, whereas T. vernalis attacked overwintered third-instar P. japonica from mid-April to early June. Adult T. vernalis were attracted to modified Japanese beetle traps and yellow pan traps and to 10% sugar water sprayed on tree foliage. Spraying sugar water directly on turf most effectively monitored T. pygidialis wasps. Parasitism rates as high as 33 and 58% were observed for T. pygidialis and T. vernalis, respectively. In the laboratory, T. pygidialis larvae progressed through five instars to cocoon formation in ≈22 d. They overwinter as prepupae. Field-collected female wasps lived 32 ± 4 d, parasitizing 22 ± 6 grubs. In...

We examined the effects of supplemental food sources on parasitism of turf-infesting white grubs (Coleoptera: Scarabaeidae) by tiphiid wasps (Hymenoptera: Tiphiidae). Survival of spring active Tiphia vernalis Rohwer and late summer active Tiphia pygidialis Allen, parasitoids of Japanese beetle, Popillia japonica Newman, and masked chafer, Cyclocephala spp., grubs, respectively, was significantly increased when wasps were provided with 10% sugar water in the laboratory. Presence of a grub for host feeding did not affect wasp longevity. Sugar sprays applied directly to turf were examined as a method for increasing grub parasitism rates. Large numbers of T. pygidialis visited turf sprayed with sugar water to feed. Parasitism of Cyclocephala spp. grubs by T. pygidialis was reduced in sugar-sprayed turf, but higher in turf plots located near sugar-sprayed turf. T. vernalis, which feeds on homopteran honeydew secretions, was never observed feeding on sugar-sprayed turf, nor did such treatments affect i...

The Japanese beetle (Popillia japonica Newman), a polyphagous scarab, feeds on certain palatable plants that are toxic, or reputedly toxic. Paralysis of the beetle after consumption of flowers of zonal geranium (Pelargonium × hortorum L. H. Bailey) has been documented, but factors affecting expression and range of this phenomenon are poorly known. Published anecdotes regarding toxicity of two other hosts, larkspur (Delphinium sp.) and bottlebrush buckeye (Aesculus parviflora Walt.), have not been empirically tested. For zonal geraniums, we compared toxicity with P. japonica of flowers versus leaves, sun-grown and shaded plants, and different-colored flowers. The progression of paralysis and recovery, as well as survival of paralyzed beetles under laboratory and field conditions, also were evaluated. Beetles became paralyzed after feeding on flowers of zonal geranium, but not by consuming leaves, suggesting the active compound is unique to flowers. Shaded or sun-grown flowers, and red-, white-, or...

We studied effects of parasitism by two Tiphia species (Hymenoptera: Tiphiidae) on burrowing behavior of their respective scarabaeid hosts and tested the hypothesis that parasitoid alteration of host hormones accounts for the observed behavioral change. In turf field-plots, third-instar masked chafer grubs, Cyclocephala sp., parasitized by native Tiphia pygidialis Allen burrowed to depths of 12-16 cm within 21 d, whereas nonparasitized grubs remained in the upper 4 cm of soil. Grubs bearing an egg or early-instar Tiphia larva were found relatively close to the surface, whereas those with a fourth- or fifth-instar parasitoid were deeper. Experiments in soil-filled, vertical observation chambers confirmed downward movement by parasitized Cyclocephala, and similar response in third-instar Japanese beetle, Popillia japonica Newman, parasitized by Tiphia vernalis Rohwer. Removal of the Tiphia egg from masked chafers was followed by initial downward movement of grubs and then a gradual ascent, suggesting that host behavior is affected both by the venomous sting and feeding by the wasp larva. Significant but inconsistent differences were found in juvenile hormone-III (JH III) titers in hemolymph taken from nonparasitized grubs or grubs parasitized for 1 or 14 d. Topical application of JH III and methoprene acid resulted in grubs moving deeper into the soil, whereas injection of 20-hydroxyecdysone did not affect grub behavior. Failure to dig deeply enough in soil when sampling for parasitized scarab grubs or Tiphia cocoons likely will result in underestimation of parasitism rates.

Patterns of feeding by Japanese beetles, Popillia japonica Newman, were studied in relation to time of day or night and to ambient temperature (Ta). We also measured beetles’ thoracic temperatures (Tth) at rest, during preflight warm up, and during flight, and observed their within-plant distributions in relation to sunlight or shade to gain insight regarding whether their in-field behavior involves physiological and behavioral thermoregulation. Finally, we studied startle response as affected by Ta and time of morning. Japanese beetles fed most extensively within trees from midmorning until late afternoon, but also substantially in evening (1800–2200 hours) and sparingly throughout the night so long as Ta was >15°C. Beetles in the field were capable of endothermy, maintaining elevated Tth independent of basking. At low to moderate Ta (19–32°C), nonflying beetles in shade or direct sunlight had Tth as much as 3.75 or 5.5°C higher, respectively, than Ta. Thoracic temperature was elevated during fl...

Callirhytis cornigera (Osten Sacken) is a gall wasp that has alternating agamic and sexual generations that develop in large, woody stem galls and small, blister-like leaf galls, respectively, on pin oak, Quercus palustris Muenchhausen. We assessed the spatial distribution of the leaf galls within leaves, shoots, canopy levels, and whole trees, and examined the relationship between leaf gall density and various tree parameters. Within leaves, proportionately more galls were located on primary lateral veins (59.5%) or midveins (38.1%), as compared with the petioles (2.0%) or secondary lateral veins (0.4%). As many as 18 galls occurred on individual leaves, but most leaves contained 0–4 galls. Some current-year shoots contained as many as 132 leaf galls, but most shoots had

Published anecdotal reports suggest that Japanese beetles, Popillia japonica Newman, feed more heavily on host plants growing in full sun than on shaded plants. We studied the effects of shading on foliar characteristics of roses (Rosa variety floribunda ‘Class Act’) and determined preference and fecundity of beetles provided with sun- or shade-conditioned leaves. Defoliation by P. japonica also was compared between sun-grown and experimentally shaded roses in the field. Leaves from plants grown in full sun were smaller and thicker than ones from shaded plants, with slightly higher tannins. Leaf toughness and nitrogen levels were not affected by shading, but leaves from sun-grown plants had relatively higher sugar content. Beetles consistently consumed more foliage from sun-grown plants than from shade-grown plants in laboratory preference tests. However, beetles fed continuously for 2 wk on leaves from sun- or shade-grown plants had similar fecundity. In the field, beetles fed somewhat more heav...

Populations of Callirhytis cornigera (Osten Sacken) and its associated community of natural enemies and inquilines were monitored on pin oak, Quercus palustris Muenchhausen, in Lexington, KY, from 1997 to 1999. The gall wasp has alternating agamic and sexual generations that differ morphologically and develop in multichambered galls on branches and single-chambered galls on leaves, respectively. There was a strong association between maximum gall diameter and the number of total stem gall inhabitants, such that proportionately more C. cornigera survived and fewer were parasitized as stem gall diameter increased. The most abundant natural enemies of the agamic generation included the hymenopteran parasitoids Sycophila spp. (Eurytomidae) and Ormyrus labotus Walker (Ormyridae), and the clerid predator Phyllobaenus verticalis (Say). The most abundant inquilines in stem galls were the cynipids Synergus sp. near lignicola and Ceroptres sp., and the dogwood borer, Synanthedon scitula (Harris) (Lepidoptera: Sesiidae). In leaf galls, Aprostocetus sp. was the most abundant parasitoid, and Ceroptres sp. was the only inquiline. The unique aspects of the C. cornigera gall system are discussed, including the relative abundance, emergence phenology, and host relationships of C. cornigera and its associated natural enemies and inquilines.

We studied ant predation on eggs and larvae of the black cutworm, Agrotis ipsilon (Hufnagel), and on eggs of the Japanese beetle, Popillia japonica Newman, on golf courses and lawns in central Kentucky. Lasius neoniger Emery accounted for >99% of the ant mounds on golf putting greens and collars. Although often regarded as a nuisance pest, L. neoniger preyed heavily upon A. ipsilon eggs on turfgrass cores implanted into putting greens, collars, fairways, and roughs. Predation on eggs was lower in fairways than in roughs, and in plots where ant populations were reduced by insecticides. When 1,600 individual 1st-instar cutworms were placed near L. neoniger nests on putting greens, 62% were attacked and killed upon their 1st encounter with the ants. Third- and 4th-instar cutworms generally fended off attacks by L. neoniger and Formica pallidifulva nitiventris Emery, but were invariably killed during encounters with Formica schaufussi Mayr and Formica subsericea Say, larger ants that are common in lawns and golf roughs. Predation on implanted Japanese beetle eggs also tended to be greater in roughs than in fairways, and fewer grubs were found in areas of golf roughs where ants were abundant than where ants had been controlled. This study suggests that predation by indigenous ants provides an important buffer against pest outbreaks on lawns and golf courses.

Attraction of Japanese beetles, Popillia japonica Newman, to 17 compounds typical of those released by undamaged and insect-damaged angiosperm leaves was compared in replicated field trials. Eight compounds attracted significantly more beetles than did an unbaited trap; however, the 2 most attractive single compounds, phenylacetonitrile and ( Z )-jasmone, were only ≍10% as effective as geraniol, a component of commercial lures. Progressive pairwise addition of less attractive volatiles to a blend of phenylacetonitrile and ( Z )-jasmone resulted in increasing beetle capture. The relative attractiveness of blends of conifer/eucalyptus, fruit-like, and floral odors, plus a complete mixture of these, also was tested. Although the floral, fruit-like, and complete mixtures captured more beetles than did the conifer/eucalyptus blend or phenylacetonitrile alone, our results suggest that this polyphagous insect is likely to be attracted to many naturally occurring plant volatiles, and that as the number of components in a volatile blend increases, so will its attractiveness. The complete mixture of volatile compounds also attracted more green June beetles, Cotinis nitida (L)., than did the fruit-like, floral, or conifer/eucalyptus blends.

We studied the close range olfactory response of Japanese beetles, Popillia japonica Newman, to constitutive or feeding-induced volatiles from leaves of 4 maple species differing in susceptibility to defoliation. In pitfall arenas, intact leaves of susceptible species, Acer palmatum Thunberg and A. platanoides L., were not significantly more attractive than those of resistant maples, A. rubrum L. and A. saccharinum L. Consistent with these results, the compounds emitted by intact maple leaves were generally similar across resistance groupings. For each maple species, leaves that had been damaged overnight by Japanese beetles attracted significantly more beetles than did undamaged leaves. Beetles did not discriminate between damaged leaves of susceptible and resistant maple species. Significant differences were noted, however, in the types of feeding-induced compounds emitted by susceptible and resistant maple leaves. Specifically, leaves of susceptible species emitted relatively higher amounts of esters with fruit-like odors and the floral fragrance compound linalool, whereas leaves of resistant maples emitted more terpene hydrocarbons. Possible roles of volatile compounds as attractants and feeding stimulants, or as feeding deterrents, for the Japanese beetle are discussed.

The hypothesis that feeding-induced plant volatiles are responsible for aggregation of Japanese beetles, Popillia japonica Newman, on leaves was tested using clonal grape plants, Vitis Labrusca L. The attractiveness of undamaged vines, undamaged vines with nonfeeding beetles, vines with fresh feeding damage, and vines with overnight feeding damage was compared in replicated field trials by placing the treatments in the field in the morning and counting the number of beetles that landed on the plants throughout the day. Many more beetles were recruited to vines with overnight feeding damage than to any of the other treatments, indicating attraction to feeding-induced volatiles. Furthermore, the low number of beetles attracted to vines with nonfeeding beetles or freshly damaged vines provided evidence against the existence of a putative aggregation pheromone. Subsequently, we examined the emission of volatiles from grape vines in situ. During the period of peak emission (1200–1500 hours), emission from vines with overnight feeding damage was almost 65 times higher than from undamaged vines. Aliphatic compounds and terpenoids were the major classes of compounds emitted by the beetle-damaged vines. The implications of feeding-induced volatiles in host-finding and mate location by this polyphagous insect are discussed.

Adult females of the southern masked chafer, Cyclocephala lurida Bland, produce a volatile sex pheromone that attracts conspecific males. Previously we documented that extracts of 3rd-instar Cyclocephala spp. grubs contain one or more compounds that attract males and stimulate copulatory attempts when these males arrive at the source of the odor. Attraction of males to larvae appears to be undocumented for any other insect species. We examined developmental expression of the production of this attractant within Cyclocephala spp., and evaluated hexane extracts of other species of scarabaeid grubs for attractiveness to C. lurida or conspecifics. We found that the attractant is not limited to the postoverwintering last instar, but rather is present in all larval stages and in male and female pupae. Extracts of Cyclocephala spp. grubs also attracted males of the northern masked chafer, Cyclocephala borealis Arrow. Hexane extracts of 3rd instars of Japanese beetles, Popillia japonica Newman, and green June beetles, Cotinis nitida L., were not attractive to male C. lurida , indicating that there is some phylogenetic specificity to this unusual production of a sex-specific attractant. Third instars of C. nitida do not attract conspecific males. Studies of male attraction to conspecific immature stages in Cyclocephala spp. and other Scarabaeidae may provide insights into the evolutionary origins of chemical communication systems.

Ant-exclusion to facilitate biocontrol by endemic natural enemies was investigated for suppressing infestations of two coccids, calico scale, Eulecanium cerasorum (Cockerell), and magnolia scale, Neolecanium cornuparvum (Thro), in landscape settings. Application of sticky bands combined with basal trunk sprays resulted in 92-100% reduction in counts of honeydew-seeking ants, mainly Formica subsericea Say, ascending large, scale-infested sugar maple (Acer saccharum Marshall) trees. Ant-exclusion was associated with increased numbers of green lacewing, mainly Chrysoperla rufilabris (Burmeister), larvae and spiders on multiple sample dates, and 54 and 69% fewer surviving scale nymphs after the first and second growing seasons. Foliar sooty mold accumulation was also significantly reduced where ants were excluded. In feeding trials, C. rufilabris larvae collected from the tree canopies consumed large numbers of settled scale nymphs. On another site, ant-exclusion led to 82% reduction in magnolia scale densities on Magnolia stellata (Siebold & Zuccarini) Maximowicz, compared with controls, after 1 yr. Nine and 10 ant species were found tending calico and magnolia scales, respectively, at landscape sites in central Kentucky, and in situ observation trials showed that many of them aggressively attack approaching lacewing larvae. Our results suggest that where ants are closely associated with soft scales on woody landscape plants, ant-exclusion has potential as a sustainable pest management strategy.

The Japanese beetle, Popillia japonica Newman, has an unusually broad host range among deciduous woody plants, yet it feeds only sparingly, or not at all, on certain species in the field. We evaluated beetles' preference, survival over time and fecundity on eight woody plant species historically rated as susceptible or resistant and, after verifying those ratings, tested whether resistance is correlated with so-called quantitative defense traits including leaf toughness, low nutrient content (water, nitrogen, and sugars), and relatively high amounts of tannins or saponins, traditionally associated with such plants. We further tested whether species unsuitable for Japanese beetles are also rejected by fall webworms, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), the expected outcome if the aforementioned traits serve as broad-based defenses against generalists. Choice tests supported historical resistance ratings for the selected species: tuliptree, lilac, dogwood, and Bradford callery pear were rejected by Japanese beetles, whereas sassafras, cherry plum, Virginia creeper, and littleleaf linden were readily eaten. Rejected species also were unsuitable for survival over time, or egg-laying, indicating beetles' inability to overcome the resistance factors through habituation, compensatory feeding, or detoxification. None of the aforementioned leaf traits was consistently higher or lower in the resistant or susceptible plants, and plant species rejected by Japanese beetles often were not rejected by fall webworms. Specialized secondary chemistry, not quantitative defenses, likely determines the Japanese beetle's dietary range among deciduous woody plant species it may encounter.

Adult activity of native green June beetles, Cotinis nitida L., and invasive Japanese beetles, Popillia japonica Newman, peaked in late July in Kentucky coincident with later stages of veraison in early- and midseason ripening grape (Vitis spp.) cultivars. Most C. nitida feeding aggregations sampled on clusters of early-ripening grapes in the research vineyard also contained Japanese beetles. Assays showed C. nitida generally are unable to bite into intact ripe grape berries, whereas Japanese beetles readily do so. The beetles' disparate biting ability is likely because of differences in their mandibles, which are sharply pointed and opposable in P. japonica compared with C. nitida mandibles that are bluntly spatulate, do not meet at their tips, and seemingly are only suited for feeding on fruit pulp or other soft food. Japanese beetles were shown to facilitate C. nitida feeding by biting through the skin and providing access to the soft berry pulp. Juice from early- and midseason ripening grape cultivars with relatively high sugar content elicited the greatest feeding by P. japonica. A scenario is suggested wherein Japanese beetles open wound sites and contaminate fruits with yeasts that induce fermentation volatiles that attract C. nitida. Japanese beetles had difficulty biting berries of Sunbelt, a late-ripening cultivar. Phenological resistance, i.e., planting cultivars that ripen after peak flight, could be an effective management strategy. Establishment of P. japonica in grape-growing regions of the southeastern United States will likely elevate the pest status of C. nitida in vineyards.

Chestnut blight fungus, Cryphonectria (Endothia) parasitica , causes bark and wood deformity to the lower bole of scarlet oak, Quercus coccinea L., but does not kill the tree. We tested the hypothesis that C. parasitica infection stresses the tree and predisposes it to attack by the twolined chestnut borer, Agrilus bilineatus (Weber). Scarlet oaks with obvious disease symptoms attracted significantly more A. bilineatus , cerambycids, and scolytids than did apparently healthy trees. However, only 9 of 21 diseased trees were successfully colonized. Total nitrogen and tannin concentrations of the phloem did not differ significantly between diseased and control trees; however, phenolic concentrations were significantly higher in the phloem of diseased trees that were colonized by borers. Total carbohydrate concentrations of xylem and phloem in July did not differ significantly between diseased and control trees, even in those diseased trees that were colonized. However, starch concentrations of the outer sapwood were slightly lower in all diseased trees. This tree decline complex is unusual in that the apparent predisposing stress, C. parasitica , did not reduce radial growth or total carbohydrates, which are generally regarded as indicators of tree vigor.

Color is important in optimizing capture rate of male lilac borers, Podosesia syringae (Harris), in pheromone traps. Significantly more moths were captured with black, brown, or red traps than with other trap colors tested. White traps were consistently poorest. Painting dark-colored traps with a contrasting band did not increase their effectiveness. Although dark-colored Pherocon® 1C traps were up to five times more effective than standard white traps, traps painted on the exterior only failed to catch significantly more borers than did solid white traps. These findings appear to result from attraction and orientation of pheromone-stimulated males to dark shapes, rather than male hesitancy to enter a white trap. The role of visual stiumli in the searching behavior of male clearwing moths is discussed.

The southern masked chafer, Cyclocephala immaculata Olivier, and the northern masked chafer, C. borealis Arrow, are serious pests of turfgrass in central Kentucky. The temperature threshold for pupation of overwintering C. immaculata grubs was determined experimentally as 10.8°C. Trapping studies during 1979 and 1980 indicated that first emergence and peak flight of males occur approximately 1 to 2 weeks earlier for C. borealis than for C. immaculata . Thermal unit accumulations in air and soil were closely correlated with the first emergence of beetles, but they were less useful for predicting the date of 50 and 90% flight. Once emergence has begun, activity of masked chafers is more closely related to rainfall patterns than to temperature.

Chlorosis and reduced net photosynthetic CO2 assimilation were quantified for Euonymus fortunei plants infested with the Euonymus scale, Unaspis euonymi (Comstock). Leaf chlorosis resulted from chloroplast destruction, especially in the palisade parenchyma cells. Reduction in chlorophyll per scale was ca. 14-fold greater for female scales on leaves than for males. Feeding by two generations of scales resulted in 49% average reduction in leaf chlorophyll and 63% reduction in rate of whole-plant photosynthetic CO2 assimilation relative to uninfested controls. However, there was no significant change in CO2 assimilation per unit of chlorophyll, suggesting that the reduction in net CO2 assimilation caused by euonymus scale is primarily a consequence of chlorophyll loss.

Relative reduction in growth of root and shoot systems of the woody plant, Euonymus fortunei (Turcz) Hand.-Mazz., caused by the euonymus scale, Unaspis euonymi (Comstock) (Homoptera: Diaspididae), was determined, and the distribution and development of scales on the plants were investigated at the end of one generation. Weight of total abscised leaves increased, whereas weight and area of intact leaves, stem weight, and plant height decreased with increasing scale density. Root weight was not affected by scale infestation, but the root/shoot ratio increased with increasing density of scales. More females than males settled on the stems, whereas the sex ratio was nearly equal on the leaves. The proportion of scales reaching maturity was higher for females on stems than on leaves, and higher for males on leaves than on stems. This indicated either differential mortality or slower development of the sexes, depending upon settling site.

Eggs of Cyclocephala immaculata Olivier absorb water from the soil, increasing ca. threefold in weight during the first 10 days of embryonic development. Eggs developed normally at soil moistures of 12.5% and above, but shriveled and died in drier soils. Length of incubation period, survival, and final egg weight did not differ at soil moistures within the range required for survival; however, few eggs were laid in dry soil or when soil moisture approached field capacity. Oviposition in soil moisture gradients indicated that the depth at which eggs are laid can vary in response to moisture levels. The chorion of the egg is covered densely and uniformly by minute tubercles, but specialized hydropyles are absent. The eggs are most susceptible to desiccation when newly laid or close to hatching, but are relatively resistant during the middle stage of development. These differences are associated with changes in the thickness of the serosal cuticle.

Chlorpyrifos, bendiocarb, trichlorfon, and isofenphos were applied as surface sprays to Kentucky bluegrass turf, and effects on nontarget arthropods were measured. The most abundant families of predaceous Insecta, Araneida, and Acari were Staphylinidae, Erigonidae, Parasitidae, and Eupodidae. Chlorpyrifos and isofenphos had the greatest impact on predaceous arthropods, with some taxa significantly reduced for at least 6 weeks. Effects of bendiocarb and trichlorfon were generally less severe and more temporary. Oribatid mite populations were apparently unaffected by the insecticides. Bendiocarb increased trap catches of ants for up to 2 weeks after application.

Seasonal flight of the lilac borer, Podosesia syringae (Harris), was monitored with pheromone traps during 1980–1982, and cumulative emergence was related to physiological time (i.e., degree-days [DD]). A base temperature of 10°C yielded the lowest coefficient of variation for DD summations to first catch, and was therefore selected for use in the linear heat unit system. First capture of lilac borer males in Kentucky ranged from 13 April to 6 May, and corresponded to a mean DD accumulation from 1 January of 168.9 in Lexington and 189.9 in Louisville. Flight in both cities peaked from late May to early June and ended by mid-July. Of three forecasting methods, average DD summations or projected DD requirements from a regression model were more reliable than average calendar dates for predicting optimum treatment dates in Louisville.

Replicated plots (112.2 m2) of Kentucky bluegrass turf were maintained for 4 yr on a schedule of fertilizer, herbicide, and insecticide treatments, or were unmanaged except for mowing. Impact of the high-maintenance program on predators, decomposers, and nontarget herbivorous insects was determined from pitfall-trap collections, soil and thatch extractions, and sweep-net and formalin-drench samples. Trap catches of predaceous arthropods, specifically Araneae, Staphylinidae, and Carabidae, were significantly reduced by insecticides, particularly late-summer soil treatment with diazinon. Predators repopulated treated plots by the following spring. Chrysomelidae were more abundant on high-maintenance plots in spring. Soil and thatch pH decreased significantly and thatch accumulation more than tripled under the high-maintenance program. However, earthworms were relatively unaffected, and oribatid mites were generally more abundant in high-maintenance plots. This suggests that thatch accumulation was probably more a consequence of increased vegetative production than of decreased decomposition due to depletion of soil invertebrates. Although high-maintenance lawn-care programs affect many groups of nontarget invertebrates, this study suggests that the effects are variable and in some cases less severe than would be expected, given the quantity and frequency of pesticide and fertilizer use.