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The mealybug Oracella acuta, native to the southeastern US, was accidentally introduced into slash pine plantations in Guangdong Province in China in 1988. A classical biological control program was initiated in 1995, and the parasitoids Allotropa oracellae, Acerophaus coccois, and Zarhopalus debarri were imported from the US. A total of 19 972 parasitized mealybugs were shipped to China from 1996–2004, from which 15 430 wasps emerged, 12 933 of which were the three target species. Efforts to establish a mass-rearing program for the parasitoids in China failed. Five field release sites were established, and 6 020 parasitoids were released. Only 118 individuals of the three imported species were collected during establishment checks, although several wasps were collected 1–2 years after the last parasitoid release. Over 2 000 Anagyrus dactylopii, a cosmopolitan parasitoid, emerged from the parasitized mealybugs collected, a majority from the Taishan area near the site of the original introduction of O. acuta. To date the imported parasitoids have failed to establish, and natural enemies have not noticeably reduced mealybug populations.

Feeding damage by larval coneworms (Lepidoptera: Pyralidae) on flowers and cones of pines can cause significant economic losses in pine seed orchards in the southern USA (Ebel et al. 1980, USDA Forest Service GTR SE-8, Asheville, NC). The south coastal coneworm, Dioryctria ebeli Mutuura & Monroe, is a common pest in seed orchards of slash pine (Pinus elliottii L.) in the coastal region of southeastern USA, particularly Florida (Ebel et al. 1980). With multiple generations per year, infestations of D. ebeli can be severe, especially in seed orchards infected by the southern pine cone rust, Cronartium strobilinum Hedgc. & Hahn (Merkel 1958, J. Forestry 56:651 ).

The pine-feeding mealybug, Oracella acuta (Lobdell), was accidentally introduced and established in Guangdong Province, China, in 1988 (Sun et al. 1996, J. For. 94: 27-32). It spread rapidly through the extensive plantations of exotic slash pine, Pinus elliottii Englem. var. elliottii, a species native to the U.S. Total volume growth loss has exceeded 33% in some cases, though tree mortality has not been reported (Ren et al. 2000, Natur. Enemies of Insects 22: 140-143). Oracella acuta is seldom a pest in the U.S. due to an effective natural enemy complex (Clarke et al. 1990, Environ. Entomol. 19: 99-103; Sun et al. 2002, J. Entomoi. Sci. 37: 177-181). Outbreaks occur when natural enemy populations are drastically reduced, particularly by insecticide applications (Clarke et al. 1992, J. Econ. Entomoi. 85: 1246-1252). Sun et al. (2004, J. Entomol Sci 39: 11-22) conducted preliminary studies of the parasitoid complex of 0 . acuta in the U.S. to evaluate the potential for a classical biological control program against the mealybug in China. Two of the predominant parasitoids of 0. acuta were Allotropa n. sp. (Platygastridae) and Zarhopalus debarri Sun (Encyrtidae). Zarhopalus debarri is a solitary endoparasitoid that primarily attacks adult females. Only one egg is deposited per 0. acuta female. Allotropa n. sp. prefers adult females, but will attack second and third instar females. This species is gregarious and often lays multiple eggs in larger hosts. The complete life cycle of both species averages 26 days at 27"C, with the female adult stage averaging 6 days. The abundance of the two species may vary seasonally, annually, or by site. Studies on natural enemies and their host in their native country can provide insight into the nature of the interspecific relationships and help guide the selection of appropriate

The parasitoid complex of the mealybug Oracella acuta (Lobdell) was examined in two field populations in Georgia in 1995–96. Allotropa n. sp. and Zarhopalus debarri Sun were the primary endoparasitoids emerging from O. acuta. Adult abundance varied seasonally, with Allotropa n. sp. numbers peaking in June and Z. debarri in September. Parasitism rates of female O. acuta exceeded 60% at one site and ranged from 24 to 29% at the other site. The adult female was the preferred host stage for parasitism (76%), though Allotropa n. sp. and the endoparasitoid Acerophagus coccois E. Smith occasionally utilized second and third instar females as hosts. These two species exhibited gregarious parasitism, with up to 5 Allotropa n. sp. or 4 A. coccois emerging from a single host. Adult longevity of female and male Z. debarri averaged 6.4 and 5.3 days, respectively, and access to a food source usually increased adult lifespan. Female Z. debarri contained an average of 119 eggs, compared to 74 eggs per female for Allotropa n. sp.

Larvae of the Southern pine coneworm, Dioryctria amatella (Hulst) (Lepidoptera: Pyralidae), were collected monthly during the growing seasons of 1996 and 1997 from loblolly pine, Pinus taeda L., seed orchards in Alabama, Florida, Georgia, South Carolina, and Virginia, and examined for pathogenic microorganisms. One fungus, Beauveria bassiana (Bals.) Vuill, a granulosis virus (Baculoviridae: Eubaculovirinae), and a protozoan (phylum Microspora) were found. Five larvae from three localities were infected with B. bassiana, 37 larvae from six localities were infected with the granulosis virus, and 69 larvae from 5 locations were infected with the microsporidian. Laboratory trials confirmed that B. bassiana and the granulosis virus caused coneworm mortality. B. bassiana isolates from all three locations were equally virulent to late instar larvae. Spores of the unidentified microsporidian are free, elongate oval, binucleate and contain 13-14 turns of an isofilar polar filament. The primary sites of in...

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

Because Dioryctria amatella (Hulst) is a key pest in loblolly pine, Pinus taeda L. (Pinaceae), seed orchards in the southeastern United States, improved timing of insecticide applications would be valuable for its control. To time two fenvalerate (Pydrin® 2.4 EC) applications we tested four variations of a degree-day model that was developed to predicted when various proportions of D. amatella eggs would hatch during the spring generation. We compared reductions in Dioryctria spp. cone damage to unsprayed checks and a standard operational spray regime of four monthly applications of fenvalerate. In addition, we examined seeds from healthy cones to determine if sprays to control D. amatella also reduced seed damage caused by Leptoglossus corculus Say (Heteroptera: Coreidae) and Tetyra bipunctata (Herrich-Schäffer) (Heteroptera: Scutelleridae). Trials were conducted from 1984 to 1986 in two orchards in South Carolina and one in Alabama. Degree-day accumulations (threshold = 11 °C) were begun on the day when the cumulative number of male D. amatella equaled or exceeded five captured in 15 Pherocon 1C® traps baited with 100 μg of Z-11-hexadecenyl acetate. One application per year was insufficient to control D. amatella or reduced seed-bug damage. Two sprays based on D. amatella phenology significantly reduced coneworm and seed bug damage, and were as effective as four sprays applied monthly. None of the treatments reduce spring cone losses, which are primarily caused by Dioryctria merkeli Mutuura and Monroe. Several variations of the model performed well, but we suggest that the best, based on efficacy and ease of use, was when sprays were applied immediately after five males were caught (degree-day = 0) and again when the model predicted 50% of the spring generation eggs had hatched.

Field studies were conducted in the United States and Canada to determine the response of the white pine cone beetle, Conophthorus coniperda (Schwarz), and the red pine cone beetle, Conophthorus resinosae Hopkins, to two potential inhibitors, conophthorin and verbenone, of pheromone communication. Trap catches of male C. coniperda and C. resinosae were significantly reduced and generally declined with increasing concentrations of conophthorin in traps baited with the pityol, a female-produced pheromone. Verbenone did not significantly reduce trap catches of C. coniperda. Conophthorin, but not verbenone, significantly reduced cone attacks by C. coniperda when placed near cone clusters. The twig beetles, Pityophthorus cariniceps LeConte and Pityophthorus puberulus (LeConte), responded to traps with pityol and α-pinene baits alone or with conophthorin. Thanasimus dubius (F) (Coleoptera: Cleridae) was attracted to the pityol and α-pinene, but conophthorin had no effect on attraction of this generalist bark beetle predator. Verbenone significantly reduced trap catches of T. dubius in pityol-baited traps.

Synthetic sex pheromones released in a loblolly pine, Pinus taeda L. (Pinaceae), seed orchard interfered with the ability of male coneworm moths, Dioryctria Zeller spp. (Lepidoptera: Pyralidae), to locate traps baited with sex pheromones or live females. Pherocon 1C® traps baited with synthetic pheromones or live conspecific females were hung near the center of two 1.2-ha circular plots during emergence of Dioryctria amatella (Hulst), Dioryctria disclusa (Heinrich), and Dioryctria merkeli (Mutuura and Munroe). In a paired design, trap catches for the mating-disruption treatment with synthetic pheromone dispensers consisting of three polyvinyl chloride rods placed in every tree were compared with the control treatment. Treatments were alternated at intervals of 2–3 d. Trap catches of D. amatella were reduced by 91% when plots were treated with 2.5 g/ha of Z-11-hexadencenyl acetate. Catches were reduced by 99.5% for D. disclusa and by 97% for D. merkeli when plots were treated with 12.5 g/ha of Z-9-tetradecenyl acetate, whereas catches of D. amatella were unaffected by this mating-disruption treatment. Daily disappearance of Z-9-tetradecenyl acetate from the dispensers averaged 0.46 g/ha or less. Manually placing dispensers on nylon lines in the tops of trees was an effective method for releasing synthetic Dioryctria pheromones in the orchard. These data suggest it may be feasible to prevent mating of Dioryctria spp. in pine seed orchards by using synthetic pheromones for mating disruption, but large-scale tests will be required to demonstrate cone protection.

Inundative releases of Trichogramma exiguum Pinto and Platner were evaluated for suppression of the Nantucket pine tip moth, Rhyacionia frustrana (Comstock), in first-year loblolly pine, Pinus taeda L., plantations. Three releases, spaced 7 d apart, were made in three 0.4-ha plots during second-generation R. frustrana egg deposition. Each release included three cohorts of T. exiguum developmentally separated by 25 degree-days. Mean ± SD field release rate for each cohort was 328 238 ± 88 379 females/ha. Mean T. exiguum emergence under laboratory conditions for released cohorts was 96 ± 2%, with 74 ± 3% females, of which 1 ± 1% of females displayed brachyptery; female longevity was 18 ± 3 d. Field emergence averaged 96 ± 4%. Parasitism of R. frustrana eggs was significantly increased, ranging from 40 ± 19 to 73 ± 22% in T. exiguum-treated plots and 17 ± 17 to 67 ± 21% in control plots. Data from all treated plots combined showed R. frustrana egg survival (hatching) was significantly reduced by 46%, and larval populations were significantly reduced by 60%. There was no significant difference in the percentage of terminals damaged between T. exiguum-treated (31 ± 16%) and control plots (45 ± 10%); however, length of terminal damage was significantly lower in treated plots. The percentage of damage to top whorl shoots was significantly lower in T. exiguum-treated plots compared with control plots, but there was no significant difference in length of tunneling damage. Damage to remaining shoots was not significantly different between T. exiguum-treated and control plots. Microhabitat significantly influenced both mean maximum and minimum temperature and the number of consecutive hours per day that were at or above 35 °C (critical temperature for T. exiguum survival). Soil surface with no cover had the greatest number of hours at or above 35 °C, followed by soil surface with herbaceous cover, and canopies of small trees (0.4 m tall). Canopy habitats in larger trees (0.9–1.8 m tall) had the most moderate temperature conditions. Parasitoid emergence was significantly reduced in response to increasing number of consecutive hours at or above 35 °C. Predation of parasitoids prior to emergence was significantly affected by microhabitat and by the length of time capsules were in the field before T. exiguum emergence (i.e., cohort number).

Zarhopalus debarri Sun sp.nov. reared from the loblolly pine mealybug, Oracella acuta (Lobdell), in the southeastern United States is described.

A southwide efficacy test of reduced rates of azinphosmethyl (Guthion®) for control of seed and cone insects in loblolly pine seed orchards was conducted in 1992. In each of nine loblolly pine (Pinus taeda L.) seed orchards, an untreated (no protection) check and two of five possible rates of Guthion® (1.0, 1.5, 2.0, 2.5, or 3.0 lb ai/ac/application) were randomly assigned to three test plots. Insecticide treatments improved first-year conelet survival, second-year cone survival, sound seeds per cone, and sound seeds per conelet at nearly every rate. There was no trend of better protection with increasing rates of Guthion®. The 1.0 lb ai/ac rate was as efficacious as the EPA-registered maximum aerial rate of 3.0 lb ai/ac. Based on these results, orchard managers should consider reduced rates of Guthion® for operational cone and seed insect control programs. South. J. Appl. For. 22(2):106-110.

Four major monoterpenes, (±)- α -pinene, l( S )-(–)- β -pinene, ( R )-(+)-limonene, and myrcene are found in the cones of eastern white pines, Pinus strobus L. Mixtures of these, as well as, α -pinene or β -pinene alone, increased catches of male white pine cone beetles, Conophthorus coniperda (Schwartz), in traps baited with the female sex pheromone, (±)- trans -pityol. The monoterpenes by themselves as mixtures or individually ( α -pinene, β -pinene) were not attractants for males or females. Traps baited with (±)- trans -pityol and α -pinene caught as many, or significantly more beetles than those baited with pityol and a four monoterpene mixture (1:1:1:1) used in seed orchards in North Carolina, Ohio, and Virginia. Three beetle-produced compounds, conophthorin, trans-pinocarveol, and myrtenol did not enhance catches of males or females in (±)- trans -pityol-baited traps. Racemic E -(±)- conophthorin, E -(−)- conophthorin, and E -(+)- conophthorin significantly reduced catches of males in traps baited with (±)- trans -pityol alone. Female C. coniperda were not attracted to any of the host- or beetle-produced compounds tested. The study demonstrated that traps with baits releasing (±)- trans -pityol at about 1mg/wk with (±)- α -pinene (98% pure) are potentially valuable tools for C. coniperda pest management. Baited traps can be used to monitor C. coniperda populations or possibly to reduce seed losses in a beetle trap-out control strategy.

The white pine cone beetle, Conophthorus coniperda, is a serious pest of seed orchards. The sex pheromone (+)-trans-pityol, (2R,5S)-2-(1-hydroxy-1-methylethyl)-5-methyltetrahydrofuran, shows considerable promise to manage the cone beetle populations in seed orchards. Our work confirms that pityol is an effective attractant to capture male C. coniperda. Traps need to be placed in the tree crown, preferably in the cone-bearing region, to trap out more insects. Japanese beetle traps were superior to the Lindgren funnel traps in capturing insects and trap colour had no significant effect. Commercially available bubble caps for dispensing pheromone were as effective as the experimental ‘vial and wick’ and the glass capillary tube units. Pityol released at about 0.1 mg m day−1 (100 female equivalents) was effective, and higher (more expensive) rates did not significantly improve trap catch.

Loblolly pines, Pinus taeda L., were banded in three seed orchards in Georgia to prevent the red imported fire ant, Solenopsis invicta (Buren), from tending infestations of striped pine scales, Toumeyella pini (King). Ant activity had no effect on female scale insect survival as numbers per shoot were never significantly different between check and banded trees in any of the orchards. Parasitism of females rarely differed between treatments, with higher rates twice in one orchard on unbanded trees and once in another orchard on banded trees. There also appeared to be no treatment effects on predator numbers. Coincident populations of the mealybug Oracella acuta (Lobdell) and the woolly pine scale, Pseudophilippia quaintancii Cockerell, on the shoots also were unaffected by the presence of fire ants.

In 1991, a Southwide study to evaluate the efficacy of bifenthrin (Capture®) for cone and seed insect control was established in six loblolly pine (Pinus taeda L.) and three slash pine (P. elliottii Engelm.) seed orchards. A control (no treatment), Capture® (bifenthrin), and Guthion® (azinphosmethyl) treatments were established in each seed orchard. Five aerial sprays were used to apply the insecticides during the growing season. At each spray Guthion® was applied at 3 lb ai/ac. Capture® was applied at 0.2 lb ai/ac for the first spray and 0.1 lb ai/ac for the other four sprays. Under the conditions of this study, Capture® was as effective in controlling cone and seed insects as the standard operational Guthion® treatment. Insecticide treatment resulted in a 42% and 17% increase in the number of sound seeds produced per conelet for loblolly and slash pine, respectively. Local need registration (24C) exists in several states, and seed orchard managers can currently use Capture® in Alabama, Arkansas, Georgia, Louisiana, Mississippi, Oklahoma, South Carolina and Tennessee. Seed orchard managers in other southern states need to determine if a 24C label is available in their state prior to useage. South. J. Appl. For. 18(1):72-75.

High volume sprays of azinphosmethyl, chlorpyrifos, fenvalerate, permethrin, and phosmet in various concentrations and formulations were simulated on loblolly pine (Pinus taeda L.) foliage in a pine seed orchard in northern Georgia. Persistence of these insecticides under field conditions was determined by weekly bioassays with adult leaffooted pine seed bugs [Leptoglossus corculus (Say)] and gas–liquid chromatography. Fenvalerate was the most persistent insecticide tested. In the first experiment, 0.2% AI fenvalerate caused virtually 100% seed bug mortality in bioassays through the 4th week after treatment, whereas mortality from azinphosmethyl dropped to ca. 14%. By the 6th week, mortality in the fenvalerate treatment was still 91%, even after 10.5 cm of rain. The permethrin treatments persisted for 2 weeks, then mortality declined below 40% at 3 weeks. In the second experiment, fenvalerate at 0.15% AI and 0.075% AI caused 95 and 90% mortality, respectively, after 3 weeks and 16 cm of rain, and the toxicity of the 0.038% and the 0.019% AI fenvalerate treatments lasted only 2 weeks with 12 cm rain. Permethrin in Ambush® EC at 0.2% AI had initial residues of about 150 ppm and caused ca. 84% mortality for 2 weeks with 12 cm rain. Azinphosmethyl WP at 0.2% AI had initial residues of ca. 104 ppm and persisted for 1 week. Seed bug mortality from phosmet at 0.4% AI diminished quickly after 1 week in the field.

A loblolly pine, Pinus taeda L., seed orchard in Georgia received five applications of bifenthrin, fenvalerate, esfenvalerate, and perrnethrin in 1988 and 1989, and a shortleaf pine, P. echinata Miller, seed orchard in Oklahoma was treated five times in 1988 with the same insecticides, excluding perrnethrin. Infestations of striped pine scale, Toumeyella pini (King), and the mealybug Oracella acuta (Lobdell) appeared at the Georgia orchard after the third 1988 applications. Bifenthrin plots generally had numerically lower infestation levels than did plots treated with the other pyrethroids, and numbers oflive females in the bifenthrin plots were not significantly different from numbers in unsprayed plots. In 1989, a moderate striped pine scale infestation continued, mealybugs were scarce, and an outbreak of Pseudophilippia quaintancii Cockerell began. Bifenthrin plots again had lower numbers of scale insects than the other insecticide-treated plots. A severe outbreak of pine tortoise scale, Toumeyella paroicornis (Cockerell), began after two insecticide applications at the Oklahoma orchard. By September, populations were lowest in control plots, intermediate in bifenthrin plots, and highest in plots treated with the other insecticides. In June 1989, heavy infestations were still present, even though spraying had been discontinued. By the end of July, the populations had collapsed, apparently as a result of natural enemies and intraspecific competition. Large numbers of the parasites Metaphycus spp. and Coccophagus spp. were collected from old-growth foliage, whereas more predators were reared from new growth. Parasitism rates were low in both orchards during the months of the spray applications. Unsprayed plots generally had more spiders than had treated plots, and fenvalerate plots had fewer lacewings.

Evidence for a female-produced sex pheromone in the white pine cone beetle, Conophthorus coniperda (Schwarz), and the red pine cone beetle, C. resinosae Hopkins, was obtained from laboratory bioassays and field experiments conducted with C. coniperda beetles from Ontario and North Carolina. In an olfactometer, males from both species responded significantly more to volatiles from females than to volatiles from males or cones. Generally, females did not differ in their response to female-, male-, or cone-produced volatiles. Both sexes responded to host volatiles. The strong response by male C. coniperda to females was confirmed in field tests.

A loblolly pine mealybug, Oracella acuta (Lobdell), had four to five generations per year in loblolly pine ( Pinus taeda L.) seed orchards in southern Georgia. Crawlers overwintered between the needles in the fascicles or under old resin cells made by females of previous generations. Males of the overwintering generation were usually apterous, whereas males of subsequent generations were alate. Population densities did not usually differ significantly between crown levels. Populations in orchards fluctuated; these cycles were apparently caused in part by the adverse effects of aerial insecticide applications on natural enemies, a major factor in mealybug population declines. The two most abundant parasitoids were an encyrtid, Acerophagus coccois E. Smith, and a platygastrid, Allotropa sp.

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

synthesis and reduce tree growth (Walstad and others 1973). lnfestations of three scale insects and one Fenvalerate and azinphosmethyl were applied monthly by hydraulic rneab the mealybug, Oracella acuta (Lobdell), and the woolly pine scale, Pseudophilippia quaintancii Cockerell. Azinphosmethyl caused striped pine scale; ~oue the pine significant female scale and mealybug mortality, but fenvalerate tortoise scale, T. pan/i'cornis (Cockerell); and a generally d i d not. Alternating applications of the two insecticides mealybug, Orace//a am& (Lobdell). ~roduced infestations intermediate between those treated onlv with kinphosmethyl or fenvalerate. More male scale insects emerged from shoots collected at this orchard from untreated trees than Pyrethroids are more toxic to some parasitoids than from shoots receiving insecticide applications. Parasitism of T. pini to their hosts (Coats and others 1979), and pvrethroids , . . females was significantly higher on unsprayed trees only after the are less toxic'than organophosphorous insecticides third insecticide applications in 1984. Predation of female T. pini was generally lowest on trees receiving azinphosmethyl applicato crawlers of T. pini (Clarke and others 1988). tions; Populations of T. pini and 0. acuta crashed in 1984, but this Pyrethroid applications therefore may disrupt the collapse was not related to insecticide applications. host-natural enemy complex that maintains the scale Azinphosmethyl caused heavy mortality of both sexes of T. pini insects at endemic levels, leading to scale insect and 0. acuta when individual branches were hand sprayed-in a outbreaks. Such insecticide-related outbreaks of Toombs County, GA, seed orchard, while fenvalerate did not. Parasitism rates on untreated branches were significantly higher scale insects are well documented. McClure (1 97710) than rates on treated branches only at the end of the ovewintering related resurgences in populations of the elongate period. More males emerged from fenvalerate-treated shoots, and hemlock scale, Fiorinia e~terna Ferris, to reductions more parasitoids emerged from untreated shoots. in its parasitoids and predators following insecticide Ground applications of azinphosmethyl caused significant mortality application. Luck and Dahlsten (1 975) associated of scale insects and mealybugs, whereas operational aerial the use of malathion for mosquito control with applications did not. These results suggest that aerial application of insecticides, even those highly toxic to scale insects, are outbreaks of the pine needle scale, Chionaspis ineffective in controlling established scale insect infestations. pinifoliae (Fitch). Bartlett and Ortega (1 952) discovered Repeated use of fenvalerate in seed orchards increases the that the effects of DDT residues on a parasite led to possibility of scale insect outbreaks. increases in frosted scale, Lecanium pruinosum

The use of pyrethroids in southern pine seed orchards to control seed and cone insects has sometimes resulted in outbreaks of scale insects (Nord et al. 1985). Onset of these infestations has been related in part to the relatively low contact toxicities of pyrethroids (Clarke et al. 1988). Pyrethroids have lower contact toxicities than organophosphorous insecticides against crawlers of the striped pine scale, Tourneyella pini (King). Our objective was to determine if a similar relationship existed for the pine tortoise scale, Tourneyella parvicornis (Cockerell), another scale insect pest that infests southern pine seed orchards.

Soil-incorporated carbofuran (Furadan®) at 0.44 g active ingredient (AI) per seedling reduced ectomycorrhizal development by Pisolithus tinctorius and growth of 1-0 loblolly pine (Pinus taeda L.) seedlings after five months in a greenhouse test. Seedlings with P. tinctorius ectomycorrhizae and without carbofuran were significantly taller and had greater top, root, and total fresh weights than those with any other insecticide-symbiont combination. Ectomycorrhizal development by Thelephora terrestris was not significantly affected by carbofuran. Carbofuran, especially at 0.22 or 0.44 g AI per seedling, reduced seedling growth regardless of ectomycorrhizal status. Results of this greenhouse test suggest a biological interaction between carbofuran and ectomycorrhizal fungi; additional studies are needed to determine if this effect also occurs under field conditions. However, the use of this insecticide to control the Nantucket pine tip moth or the pales and the pitch-eating weevils in outplantings has the biological potential to decrease the benefits of specific ectomycorrhizae to the survival and growth of loblolly pine.

The major insects that destroy cones and seeds of eastern white pine, Pinus strobus L., were controlled with soil applications of the systematic insecticide carbofuran in orchards at Murphy and Morganton, NC, U.S.A. Carbofuran applied once a year at rates of 4.5, 9.0 or 13.5 g AI (active ingredient) per cm of diameter at breast height protected trees from the white pine cone beetle, Conophthorus coniperda (Schwarz), the leaffooted pine seed bug, Leptoglossus corculus (Say), the shieldbacked pine seed bug, Tetyra bipunctata (Herrich-Schaffer), and the white pine cone borer, Eucosma tocullionana Heinrich. Control was reflected by increased cone survival and increased yields of filled seeds per cone. Increasing the rate of application from 4.5 to 9.0 or 13.5 g generally improved control, but the improvement was not of statistical or practical significance. Carbofuran was ineffective against a seed chalcid, Megastigmus atedius (Walker). White pine clones varied in inherent susceptibility to insect attacks.

Contact toxicities of 12 insecticides to adult Leptoglossus corculus (Say) were determined. All insecticides tested were moderately to highly toxic to adult females. Five insecticides—decamethrin, carbofuran, aminocarb, fenvalerate, and bioethanomethrin—were as toxic or more toxic than the standard, azinphosmethyl, at LD90. Decamethrin (LD90 =.06 μg/g body wt.) was 29 times more toxic than azinphosmethyl at LD90. Five insecticides—carbofuran, bioethanomethrin, resmethrin, azinphosmethyl, and chlorpyrifos—were tested on males also. The first three were significantly more toxic to females than males and the latter two were equally toxic to both sexes. All but two insecticides, decamethrin and bioethanomethrin, were equally toxic or more toxic to second-stage nymphs than adult females.

The woolly pine scale, Pseudophilippia quaintancii Cockerell, had 2 generations per year in the Georgia coastal plain. Crawler activity peaked in late March-early April and late May to mid-June. First-generation males were wingless and emergence began in late April. Second-generation males were alate and their emergence peaked in early July. Populations of P. quaintancii increased during the first generation and dispersal occurred during the second. Fecundity averaged about 500 offspring per female. Populations were significantly affected by tree clone and crown level, with higher average survival in the upper crown. Parasitism of the woolly pine scale was low.

Three insecticides--Guthion® (azinphosmethyl), Pydrin® (fenvalerate), and Ambush® (permethrin)--were applied to catkins and to ovulate strobili of loblolly pines (Pinus taeda) at the time of maximum ovulate receptivity to determine their effects upon pollen viability, ovulate strobili survival, seed set, seed yields, and seed viability. Concentrations recommended for seed orchard use did not significantly reduce the number of pollen grains/ovule, in vitro or in vivo pollen germination, survival of ovulate strobili, number of developed seeds/cone, number of filled seeds/cone, germination of full seed, or cause an increase in abnormal seed germination. Operational applications of these insecticides to control the webbing coneworm (Dioryctria disclusa) should not cause adverse effects during this sensitive period of seed development in loblolly pine seed orchards.

Second-stage nymphs of the leaffooted pine seedbug, Leptoglossus corculus (Say), were highly susceptible to most of 34 topically applied insecticides, twenty-six chemicals ad Ld50 values of less than 5 μg/g of body weight. Nine insecticides — aldicarb, aminocarb, azinphosmethyl, carbofuran, dicrotophos, FMC 45498 ((−)-(Cyano) (3-phenoxyphenyl)-methyl (+)-cis-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropane-1-carboxylate), monocrotophos, propoxur, and SD 43775 (Cyano(3-phenoxyphenyl)methyl-4-chloro-alpha-(1-methylethyl)benzeneacetate) — had LD90 values of less than 1 μg/g of body weight. There was good agreement between the relative toxicities of insecticides applied topically to the leaffooted pine seedbug in these laboratory tests and the effectiveness of several insecticides previously tested in the field.

Four variables affecting pheromone-trap catches of pine coneworms, Dioryctria spp., were studied. These variables were trap design, trap density, trap location within tree crowns, and tree clone. Pherocon lC traps were most effective for capturing male D. amatella (Hulst) moths at low population densities. Traps placed near the tops of loblolly pines, Pinus taeda L., caught twice as many Dioryctria spp. males as traps at midcrown; those at the base of the crowns had very low catches. Also, there were positive correlations between D. amatella and D. disclusa Heinrich catches and trap height, i.e., traps placed in the tops of taller trees caught more moths. Placing traps in ramets of certain clones had some effect on trap catches of D. amatella and D. disclusa . Clonal differences were apparently the result of differences in the height at which traps could be placed in the ramets of each clone. Evidence of competition among traps was found at a trap density of 8 per 0.1 ha but not at 4 per 0.1 ha or lower densities.

In 1981 traps baited with synthetic sex pheromone caught webbing coneworm (Dioryctria disclusa Heinrich), moths in 47 of 63 southern pine seed orchards. Male moths were caught in Alabama, Arkansas, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, and Virginia, but not in Florida, Oklahoma, and Texas. The potential for attacks in 1982 appears to be moderate to high in about half of the orchards and is particularly high in North Carolina. This is the first demonstration of the value of pheromone-baited traps as part of an integrated pest management (IPM) approach to coneworm control in southern pine seed orchards. These inexpensive traps provide a highly specific detection technique that can easily be used by trained seed orchard personnel, thus providing early warning to trigger preventative action.

Second-instar nymphs of Leptoglossus corculus (Say) confined to shortleaf pine conelets for only 4 days caused 100% conelet abortion. The bugs fed almost exlusively on the cytoplasm of cells of the nucellar tissue. Feeding in May produced an abscission zone in only a few days and resulted in conelet abscission in less than 2 weeks. Similar ovule destruction, followed by conelet abortion, occurred in late summer after being fed upon by the same instar, but conelet abscission was prevented because of a greater proportion of tracheary elements in the conelet stalks.

Volatiles collected on Poropak Q from fusiform rust galls (Cronartium quercuum F. sp.fusiforme) of loblolly pine for 3 hr were better ovi-position stimulants forDioryctria amatella (Hulst) females than extracts of 8-hr collections. GLC analysis of these extracts showed no major differences in relative monoterpene composition, although 8-hr collections contained an unidentified compound not detected in the 3-hr collections. Comparison of volatiles from second-year loblolly pine cones with those from fusiform galls showed that both containeddl-α-pinene, (-)-β-pinene, myrcene, and (+)-limonene. Camphene was found in galls only, and relatively large quantities of β-phellandrene were identified only from cones. The five major monoterpenes found in the two host substrates were tested in an oviposition bioassay. Eighteen trials using different combinations of these terpenes showed that the combination of α-pinene, myrcene, and limonene was as attractive toD. amatella females as all other terpene combinations, including turpentine.

The striped pine scale, Toumeyella pini (King), had three generations per year in south Georgia. Females developed on snoots and males developed on needles of loblolly pine, Pinus taeda L. Generations overlapped and crawlers were most abundant in May, mid-July to early August, and late October to early November. The average fecundity was 1865 crawlers per female. Parasitism averaged ca. 15%, but the predation rate reached 50%. Coccophagus lycimnia Walker (Hymenoptera: Aphelinidae) was the most common parasitoid reared from both males and females. A pyralid larva, Laetitia coccidivora (Comstock), was a frequent predator of females.

Male Dioryctria clarioralis moths are attracted to a synthetic blend of 30 µg Z9–14:OAc, 12% E 9–14:OAc, and 5 to 10% Z11–16:OAc. The two tetradecenyl acetates have been characterized from the female sex pheromone gland. Due to the small quantities of pheromone stored by the female (

A sex pheromone component for the southern pine coneworm moth, Dioryctria amatella (Hulst), was identified as Z-11-hexadecenyl acetate (Z11–16:0Ac) and was attractive to male moths in loblolly pine, Pinus taeda L., seed orchards. Male moth catches in Pherocon 1C traps baited with a rubber septa loaded with 10, 100, 300, or 1,000 µg of Z11–16:0Ac were as good as or better than traps combining two live D. amatella females, Field tests in Alabama, Georgia, and Texas throughout the entire growing season showed that baits with 100 µg generally would be best for a monitoring trap.

Pheromone traps detected adult male Dioryctria amatella (Hulst) activity that was confirmed by light traps and sampled damaged cones during a 3-year study in a loblolly pine seed orchard. Most of the D. amatella population (>85%) occurred in two generations per year, with adult emergences from May to June and September to October. However, a small portion of the population (

Presented are the results of 4 years of research in north Florida on dicrotophos trunk implantation to control Dioryctria spp. coneworms and the slash pine seedworm, Laspeyresia anaranjada Miller, on 2nd-year cones of slash pine, Pinus elliottii var elliotti Engelm. Dicrotophos technical liquid (1.08 kg active ingredient (AI) per liter) was implanted in early May into holes drilled in the tree stems. Dosage rates of 0.8–2.0 g AI per cm of tree diameter at waist height gave 86–94% control of Dioryctria spp. and 94–100% control of M L. anaranjada on mature cones harvested in mid-September of the year of treatment. Dicrotophos implanted by Mauget® injectors at dosages of 0.6–1.4 g/cm diameter resulted in 30–81% control of Dioryctria spp. and 56–97% control of slash pine seedworm. Date of treatment may be advanced to early April and good control of both insects still be obtained. Foliage of trees implanted with dicrotophos in early May showed no phytotoxic symptoms at the dosages tested. Seeds from trees implanted with a 1.4 g per cm-diameter dosage of dicrotophos for 3 consecutive years showed no decrease in full-seed germination percentage when compared with seeds from untreated trees. Seed losses caused by the hemipteran seed bugs Leptoglossus corculus (Say) and Tetyra bipunctata (Herrich-Schaeffer) were also reduced with dicrotophos implants.

Peak oviposition by Dioryctria amatella (Hulst) females occurred from 5 to 7 days after moth emergence and ca. 80% of the eggs were laid during the period from 3 to 12 days after emergence. The threshold temperature for D. amatella egg development was determmed to be 11°C. The number of degree-days required for complete egg development ranged from a mean of 115.5 degree-days at 16°C to 84 degree-days at 28°C. The estimated number of degree-days required for egg hatch was 86.6.

The presence of a female sex pheromone in Dioryctria amatella (Hulst) was demonstrated and a bioassay procedure was developed for use in further studies. Male response to 5 concentrations of crude pheromone extract was determined. Male behavioral responses included orientation to the pheromone source, rapid circling or searching at the source, and wing fluttering. Orientation was the most commonly observed response with 90% of the males responding to 0.5 female equivalents of extract (FE). The percentage of males responding decreased slowly with decreasing concentration to 0.01 FE then-rapidly decreased at 0.005 FE. Low intensity red light enhanced male response, while low intensity white light or the presence of more than one male per test chamber reduced response.

First- and fourth-instar Dioryctria amatella (Hulst) were reared on an artificial diet at six constant temperatures in the laboratory and outdoors. Threshold temperature for larval development was 13°C, and development from newly hatched larva to pupa and larva to adult required 303 and 493 degree-days (DD), respectively. Mean DD for development of immatures in a shaded area outdoors during spring and early summer of 1984 varied only 8 DD from estimates derived from constant-temperature data. Threshold temperature did not vary with larval age.

Moths of the genus Dioryctria are important insect pests of North American conifers (Baker 1972). Of the species that occur in the southern United States, e.g., D. clarioralis (Walker), D. disclusa (Heinrich), and D. ebeli Mutuura and Munroe, the southern pine coneworm, Dioryctria amatella (Hulst), is the most destructive (Ebel et al. 1975). Our paper reports the results of laboratory tests aimed at determining the relative toxicities of commercially available or promising experimental insecticides to D. amatella larvae.

A sex pheromone component for the webbing coneworm, Dioryctria disclusa , has been identified as (Z)-9-tetradecenyl acetate. Traps baited with rubber septa impregnated with this compound at loadings of 30 to 300 μg caught the same as or significantly better than traps baited with two virgin female moths. Addition of 3 to 30% of the E isomer did not increase trap catch, and only (Z)-9-tetradecenyl acetate was found in the female extract.

Contact toxicities of nine insecticides (four organ phosphorous insecticides and five pyrethroids) were tested on crawlers of a striped pine scale, Toumeyella pini (King). Organ phosphorous insecticides were more toxic than pyrethroids. Chlorpyrifos was the most toxic, and fenvalerate was the least toxic. Residual tests showed that the pyrethroid esfenvalerate lost its toxic effects at a slightly faster rate than the organ phosphorous insecticide azinphos-methyl. Low toxicity of the pyrethroids to crawlers may be partially responsible for the rapid build-up of T. pini in southern pine seed orchards.

Pherocon 1C® traps baited with live Dioryctria disclusa Heinrich females caught more than 900 male moths in loblolly pine seed orchards at Greensboro, GA, and Georgetown, SC, from 28 May-18 June 1979. Up to 25 times as many moths were trapped in the upper than in the lower crowns of trees of 9 to 15m tall. Peak catch occurred on 6 June with an average of 25 moths per trap. Females attracted males between 2400 and 0200 h e.d.t. the first night after emergence. Only D. disclusa males were trapped, although other Dioryctria spp. were active in the orchards. Mating periodicity may be a species isolating mechanism for sympatric populations of Dioryctria spp. with overlapping moth emergence. Our field data show that female D. disclusa moths produce a sex pheromone and provide the first evidence of the usefulness of Dioryctria spp. pheromones for capturing male moths in the field. Pheromones offer a convenient, inexpensive, and specific survey technique for these forest insect pests.

During 1967 and 1968, tests were conducted to determine if a flower thrips, Gnophothrips fuscus (Morgan), and southern cone rust, Cronartium strobilinum (Arthur) Hedgcock and Hahn, could be controlled with mist-blower applications of the fungicide ferbam combined with either malathion or heptachlor. Testing was done in a seed orchard of 8- and 9-year-old slash pine, Pinus elliottii Var. elliottii Engelmann, in northern Florida. Two applications of 0.25% heptachlor or 0.75% malathion effectively reduced thrips attacks on female strobili. Malathion was the most effective and reduced total thrips attacks by 75%, and thrips kill of strobili by more than 80%. Ferbam did not deter allacks by thrips. Ferbam protected artificially inoculated strobili from infection by C. strobilinum , but the feasibility of controlling southern cone rust with mist-blower applications of ferbam in seed orchards was not substantiated because of lack of natural infection. None of the treatments adversely affected total seed yields, full seed yields, or percentage full seed germination.

From 76 to 87% of the total cone crop was located in the upper half of the tree crowns of slash pines, Pinus elliottii Engelm. var. elliottii, in Baker County, Florida. The east and south quadrants supported significantly larger crops than the north and west quadrants. The numbers of female strobili attacked by the slash pine flower thrips, Gnophothrips fuscus; cone-worms, Dioryctria spp.; or seedworms, Laspeyresia spp., did not differ significantly among the quadrants. Significantly greater numbers and percentages of cones in the upper crown were infested by Dioryctria spp. More cones in the upper crown were infested by Laspeyresia spp., but the percentage of cones infested, as well as the average number of Laspeyresia larvae per cone, did not vary significantly between levels or among quadrants. The proportion of full, empty, and seedbug damaged seed did not differ significantly among quadrants or crown levels.