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BRARI ES SMITHSONI : 5 Gy = = YY, = = O x Vip, ) = tr Gi O = = Ny A alba = Ste fee = = >’ = >" = > ” a 79) = ” ee Saluyvuai LIBRARIES SMITHSONIAN INSTITUTION NOILALILSNI_ NVINOSHLI NOILONLILSNI »X Saiyuvugi7 LIBRARIES SMITHSON f af " $3 NOILNALILSNI NVINOSHLI LIBRARIES NOILNLILSNI LIBRARIES IMITHSONIAN INSTITUTION NOILALILSNI NVINOSHILIWS Ge INSTITUTION NOILNLILSNI INSTITUTION INSTITUTION SAIYVYAREIT LIBRARIES Uh SMITHSONIAN INSTITUTION NOSHLINS S3IYVHUSIT LIBRARIES NOSHLINS S3IYVYSIT NOSHLINS S3IlYWYdII THSONIAN 4 Lsltty, Ye dif; THSONIAN THSONIAN : : f eer aCe | : ‘7: f 7 { : oo ? ra tw . 4 7 2 - 7 - . ‘ i é rn 4 1 * 1 4 1 \ i : a Rae i 3 4 ; oy, : Chet : i oy Hee wy a 7 wy . once ¥ : An aN wy oy 7 mon On ere a) , Wo, | ‘ Deen 1 oy t me a nf ce, ia nan i ’ ' ‘ i ae coger i! = : i” ' ' ak t a an ita its 4 : i... om. 2 er, , rnin ' Viet D. rufipennis 6.9705 6.93 0 0 D. pseudotsugae 6.55* 6.43% 6.95 Brood per D. ponderosae 28.00 8.50 O 0) successful D. rufipennis 19.00 33.033 0 0 gallery D. pseudotsugae 31.00 150 30.20 0 Male size° D. ponderosae 1.88 + 0.03 lool + 0. 01%* = - (x + sz) D. rufipennis 26264 0.0399 2.33 40.02 - - D. pseudotsugae ND 1,.81**+ 0.04 2.22 + 0.01 a Female size© D. ponderosae 2.09 + 0.05 1,82 + 0.03** = a Cet e=) D. rufipennis 2e231t O,07U2> 2525, 4 0.02 = = D. pseudotsugae ND 1.89 + 0.04%* 2.22 + .02 - Male ratio D. ponderosae 0.39 O05. 335 = = D. rufipennis 0.5475 0.39 | = = D. pseudotsugae ND 0.42n8 0.46 ce a Principal hosts b See Methods Average width of the prothorax ND = No measurements were taken ns,*,** Not significant, significantly different at the 95% and 99% probability levels, respectively, from mean for the principal host. J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DEc. 31, 1983 13 the three Dendroctonus species tested and that Douglas-fir is not a suitable host for mountain pine and spruce beetles. Production of mature broods in the spruce and lodgepole pine bolts by Douglas-fir beetle, in the spruce bolt by mountain pine beetle, and in the lodgepole pine bolt by spruce beetle in the laboratory indicate that populations might be main- tained in such alterntive hosts in the field. However, brood establishment and maturation following forced attacks on bolts of alternate hosts in the laboratory does not necessarily mean that natural attacks and brood development would oc- cur in live trees. For example, the Douglas-fir beetle infests western larch in addition to its principal host, but progeny survive only in felled trees (Fur- niss et al. 1981). These workers suggest that attacks by Douglas-fir beetle on western larch are due to similarities in the monoterpene composition of Douglas-fir and western larch and intermingling of odours from neighbouring attacked Douglas-fir but they cannot explain the failure of broods in live western larch. Killing of lodgepole pine by the spruce beetle during epidemics in spruce forests and killing of spruce by mountain pine beetle during epidemics in pine forests have been documented (e.g. Schmid and Frye 1977, Wood 1982). Lodgepole pine and white and Engelmann spruce, however, are not considered hosts of the Douglas-fir beetle, although felled Brewer spruce (P. breweriana S. Watts) is an occasional host (Johnson 1960). Johnson’s report and our results indicate that Douglas-fir beetle may occasionally attack lodgepole pine and some spruces in its range and that broods could mature in felled trees. Literature Cited Amman, G. D. 1978. Biology, ecology and causes of outbreaks of the mountain pine beetle in lodgepole pine forests. In Theory and practice of mountain pine beetle management in lodgepole pine forests. Symposium Proceedings, Washington State Univ., Pull, April 25-27, 1978. p. 39-53. Dyer, E. D. A. 1969. Influence of temperature inversion on development of spruce beetle, Dendroctonus obesus (Mannerheim) (Coleoptera: Scolytidae). J. Ent. Soc. B.C. 66: 41-45. Furniss, M. M., R. L. Livingston, and M. D. McGregor. 1981. Development of a stand susceptibility classification for Douglas-fir beetle. In Hazard rating systems in forest insect pest management: Sym- posium Proceedings, Athens, Georgia, July 3l-August 1, 1980. USDA For. Serv. Gen. Tech. Rept. WO-27: 115-128. Johnson, N. E. 1960. Douglas-fir beetle: A problem analysis. Weyerhaeuser Co., For. Res. Note 29, 19 p. Lanier, G. N., and D. L. Wood. 1968. Controlled mating, karyology, morphology and sex-ratio in the d. ponderosae complex. Ann. Ent. Soc. Amer. 61(2): 517-526. Massey, C. L., and N. D. Wygant. 1954. Biology and control of the Engelmann spruce beetle in Colorado, USDA For. Serv. Cir. No. 944, 35 p. McCambridge, W. F., and F. B. Knight. 1972. Factors affecting spruce beetles during a small outbreak. Ecology 53: 830-839. Safranyik, L., D. M. Shrimpton and H. S. Whitney. 1974. Management of lodgepole pine to reduce losses from the mountain pine beetle. Env. Canada, For. Serv., Forestry Technical Report 1, 24 p. Schmid, J. M. and R. H. Frye. 1977. Spruce beetle in the Rockies. USDA Forest Service, Rocky Mtn. For. and Range Expt. Stn. Fort Collins. Gen. Tech. Rept. RM-49, 38 p. Wood, S. L. 1982. The bark and ambrosia beetles of North and Central America (Coleoptera: Scolytidae), a taxonomic monograph. Great Basin Naturalist Memoirs No. 6. Brigham University, Provo, Utah, 1359 p. 14 J. ENTOMOL. Soc. Brit. COLUMBIA 80 (1983), DEc. 31, 1983 EFFECT OF HIGH DENSITY FRONTALIN BAITING ON ATTACK DISTRIBUTION OF ° DENDROCTONUS RUFIPENNIS IN SPRUCE PLOTS E. D. A. DYER! AND P. M. HALL? Environment Canada Canadian Forestry Service Pacific Forest Research Centre 506 West Burnside Road Victoria, B.C. V8Z 1M5 ABSTRACT Intensive baiting with frontalure (33% frontalin and 66% alpha-pinene) was found to affect the distribution of spruce beetles, Dendroctonus rufipennis (Kirby), among available hosts. In treated plots 23 to 63% of the beetle attacks were found in standing trees potentially capable of resisting gallery establishment, compared with less than 1% in check plots. All suitable freshly downed trees were attacked in treated and check plots but the attack densities were significantly lower in two of the three treated plots as compared with their checks. Frontalure capsules placed on the ground at various distances from standing trees failed to induce attack. RESUME Les auteurs ont constaté qu’un appatement intensif a l’aide de frontalure (33 % frontaline et 66% alpha-pinéne) influait sur la répartition des dendroctones de lépinette, Dendroctonus rufipennis (Kirby), entre les hétes disponibles. Dans les parcelles traitées, de 23 a 63% des attaques ont été observées dans les arbres sur pied potentiellement en mesure de résister a l’etablissement de galeries, com- parativement a moins de 1% dans les parcelles temoins. Tous les bois recemment abattus ont été attaqués dans les parcelles traitees et temoins, mais la densité des at- taques est significativement plus faible dans deux des trois parcelles traiteés par rap- port a leurs témoins. Les capsules de frontalure posées sur le sol a diverses distances d’arbres sur pied n’ont pas induit d’attaques. INTRODUCTION The spruce beetle, Dendroctonus rufipennis (Kirby), periodically kills large volumes of mature spruce (Picea glauca Moench) Voss, P. engelmannii Parry) in western North America (Massey and Wygant 1954; Wood 1963). This bark beetle ag- gregates at spruce billets in response to pheromones produced by the first females entering the bark (Dyer and Taylor 1968). Synthetic frontalin, a pheromone of the southern pine beetle, D. frontalis Zimm. (Kinzer et al. 1969), was shown to induce spruce beetle attack on spruce trees (Dyer and Chapman 1971). Windthrown trees are nearly always infested by spruce beetle in spruce stands with endemic beetle populations but standing trees are seldomly attack- ed. However, in such stands, frontalin baiting of standing trees will induce beetle attack even though tree resistance usually cannot be overcome (Dyer and Safranyik 1977). Baited trees, then, usually become lethal traps for beetles which would other- wise seek out windthrown trees for attack and suc- ‘Research Scientist. Retired. *Present Address: British Columbia Ministry of Forests, Protection Branch, 1450 Government St., Victoria, B.C. V8W 3E7. cessful brood production. Under epidemic condi- tions baited trees are attacked, often successfully, although tree resistance is variable (Dyer 1973, 1975). Spruce forests contain varying amounts of susceptible windthrown material which is the preferred host of spruce beetle. Thus, in considering the use of pheromone-baited trees for beetle popula- tion management, it is necessary to know what percentage of the population is caught in the lethal traps. About 4% of an endemic spruce beetle popula- tion was estimated to have attacked pheromone- baited trees while about 96% infested windthrown trees in an experiment using 100 randomly selected, frontalin-baited spruce trees scattered throughout a 766 ha spruce forest. Although the attack density was similar in standing baited trees and wind- thrown trees, the beetles attacked only the lower boles of the standing trees, but infested the entire surface of the more numerous fallen trees (Dyer and Safranyik 1977). From the same study, it was estimated that 34 baited trees per windthrown tree would capture 90% of the population in the baited trees in which the beetles could not reproduce. J. ENTOMOL. Soc. Brit. COLUMBIA 80 (1983), DEc. 31, 1983 15 The present paper reports the distribution of at- tacks by endemic spruce beetle populations in wind- thrown and standing trees when stands were baited with pheromone at a higher density than was used by Dyer and Safranyik in 1977. METHODS In 1975, paired plots of 4.05 ha, 100 m apart in mature spruce stands were replicated three times in different parts of the Naver Forest near Prince George, British Columbia. Most of the six plots con- tained one or more uninfested winter-windthrown spruce trees but, where required, other trees were felled to provide each pair of plots with similar bark-surface areas of downed trees (Table 1). Stand composition data are also shown in Table 1. One plot, selected at random from each pair served as a check and the other was treated by attaching pheromone capsules at breast height on one hun- dred spruce trees at grid intervals of 20 m throughout the plot. Additionally, one capsule was placed on the ground at the centre of each grid, ap- proximately 14.1 m from each baited tree. The cap- sules were polyethylene tubing, 1 cm (OD) x 6.5 cm, sealed at both ends, containing 2 ml fron- talure (33% frontalin, 67% alpha-pinene). After beetle flight and attack, the plots were cruised and beetle entrances were counted on all standing trees. The attacks on windfall trees were estimated by counting entrance holes in 20.3 x 25.4 cm samples of bark selected randomly on the bark surface of the tree. Depending on the length of the windfall, 8 or 12 samples per tree were taken. Population estimates are presented (Table 2 and 3) as numbers of females since they are based on estimates of entrance holes. Infested bark surface area was calculated for each of the infested standing trees and windfalls (to a 15 cm top diameter) by the following method: 1) infested standing trees: a x dbh x maximum infested height TABLE lL. Plot description data for 3 pairs of Plots. One plot of each pair treated with frontalure@ capsules at 20 m grid intervals. Standing Spruce = 19.3 cm dbh Downed spruce dbh (cm) Surface area b 2 Plot No. trees Mean SE No. trees (m_) 1 Treated 966 47.1 i eae 4 59.5 Check 911 45.8 4.5/7 5 70.4 2 Treated 881 42.7 1.14 2 32.8 Check 707 42.2 1.85 2 29.1 3 Treated 724 43.4 0.81 3 50.2 Check 940 36.8 0.90 5 49.1 a. Capsules of frontalure (33% frontalin, 67% alpha-pinene) attached to spruce tree boles. b. Standard error. 16 J. ENTOMOL. Soc. BriT. COLUMBIA 80 (1983), DEc. 31, 1983 TABLE 2. Spruce beetle attack distribution in pheromone treated and untreated plots. Attacked standing trees Downed trees Number Attacks/tree Attack density/m- Plot Baited Unbaited Mean sp* Mean S E uy 1 Treated 29 8 21.2 30.3 44.8 3.52 Check ~ Zz 0 2.8 48.1 3.92 2 Treated 29 11 32:8 44.5 38.8° 3.62 Check - r ) - 75.9 5.92 3 Treated 49 23 21-1 28.4 18.3° 3.02 Check _ 1 0 - 34.2 3.49 a. Standard Deviation b. Standard Error c. Treated and check differ at 0.05 level of significance (Mann-Whitney U Test.) 2) windfall: nm x (base diam + top diam (15 cm)) x length. 2 The Mann-Whitney U test (Siegal, 1956) was us- ed to determine differences in attack densities (Table 2). A second experiment was carried out to deter- mine whether or not pheromone capsules on the ground at various distances from spruce trees would induce beetle attack. Four replicates were establish- ed. Four trees with similar diameters and 20 m or more apart were selected in each replicate. In each group, a pheromone capsule was placed on the first tree 1.4 m above ground, on the ground within 1.5 m of the second tree, on the ground at 3.7 m from the third tree and no capsule near the check tree. After beetle flight, the trees were examined and all attack entrances were counted. RESULTS All windthrown and felled trees were attacked over the entire bole in both treated and untreated plots. However, in two of the three replicates the at- tack density in the treated plots was about half that in the check plots (Table 2). Not all of the baited trees in the treated plots were attacked. Of the 100 baited trees in each treated plot, 29, 29 and 49 trees, respectively, were attacked. An additional 8, 11 and 23 unbaited trees also became attacked in the three treated plots (Table 2 and Fig. 1). The infested trees were attack- ed from near the base to a maximum height of 4 m. The attacks were occasionally dense but averaged from 21 to 33 per tree in various plots. In the check plots an average of only about four attacks per tree occurred on a total of four attacked standing trees (Table 2). The distribution of the female beetle population based on the number of attack entrances is shown in Table 3. Female population totals within the plots were estimated by adding the attacks counted on standing trees and the calculated total attacks on windfall or felled trees. The estimated female population totals were similar in each pair of plots but more than 99% of the population in the check plots was in the felled trees, whereas in the treated plots from 37 to 77% of the beetles were in downed trees. Most of the rest of the attacks in the treated plots were on pheromone baited trees. The distribu- J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DEc. 31, 1983 iva TABLE 3. Estimated population levels of female spruce beetles in spruce forest plots of 4.05 ha (one plot of each pair treated at 20 m intervals). Plot Female beetle % of population in population felled trees 1 Treated 3450 Ties Check 3396 99.7 b 2 Treated 2585 49.2 Check 2214 99.8 b 3 Treated 2438 36.7 Check 1680 99.9 a. Capsules of frontalure (33% frontalin 67% alpha-pinene) attached to spruce tree boles. b. Significantly (p=0.05) fewer attacks than in check plots. TABLE 4. Beetle attacks per tree on four replicated groups each of 4 trees baited with pheromone capsules placed on the boles and at various distances on the ground. Position of capsule Attacks per tree in each replicate On bole 1.4 m above ground 137 34 7 196 On ground 1.5 m from tree base 0 5 0 0 On ground 3.7 m from tree base 0 ) 0 0 Control tree - unbaited 0 0 0 0 a. 33% frontalin 67% alpha-pinene in polyethylene capsules. 18 J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DEc. 31, 1983 UNTREATED PHERMONE TREATED — FALLEN x STANDING BAITED @ STANDING UNBAITED Fig. 1. Distribution of infested fallen and standing trees in check and pheromone-treated plot pairs. tion of the infested standing and felled trees in the pairs of plots is shown in Figure 1. Pheromone capsules placed on the ground in the treated plots were intended to increase the level of pheromone in the plots and aid in confusion such that naturally attractive downed trees would not be found by the attacking beetles. The effect of pheromone placed on the ground between baited trees in the treated plots could not be determined from the attack distribution. However, as shown by the results of the second experiment (Table 4) only capsules attached to the boles of trees induced any significant attack. When unbaited trees were in- fested, they were usually adjacent to densely attack- ed baited trees where naturally produced pheromones could also affect attack behavior. The poor attractiveness of the ground-based pheromone may be due to the absence of necessary host- produced volatiles which would act as synergists to the synthetic frontalin mixture. The host volatiles would be in addition to the alpha-pinene included with the frontalin in the capsules. DISCUSSION Frontalure capsules, attached to spruce trees on a 20-m grid in forest plots, attracted part of the endemic spruce beetle population into potentially resistant standing trees. However, the remaining population in suitable hosts such as windthrown and felled trees would provide a continuing beetle hazard for future years. Dispensing larger amounts of attractant in the forest might confuse the beetles so that they could not find scattered hosts such as windthrown trees. However, in the treated plots from 37 to 77% of the beetles found and infested the felled trees despite the density of pheromone capsules used in this ex- periment. Baiting at even greater densities would be costly over large areas and would be impractical to apply to large numbers of individual trees. Aerial application of pheromone dispensers is likely to be ineffective, at present, as indicated by the poor bee- tle response to ground-based pheromone release. An improved pheromone complex, incorporating the required host tree volatiles, may make this strategy practical for spruce beetle. Currently, however, the precise pheromone complex for spruce beetle is not known. It should be emphasized that baited standing trees cannot always be expected to show a high degree of resistance to beetle attack and thus may not cause brood failure. This could, in some cir- cumstances, increase a beetle problem. If this technique is used, treated stands should be harvested and processed prior to the next beetle at- tack period. For the present, it would be best to look for more efficient methods of attracting beetles to insecticide-treated, pheromone baited trap trees and to practise better forest management to reduce or remove windthrown trees in which the beetles breed so abundantly. J. ENTOMOL. Soc. Brit. CoLumBiA 80 (1983), DEC. 31, 1983 19 REFERENCES Dyer, E. D. A. 1973, Spruce beetle aggregated by the synthetic pheromone frontalin. Can. Jr. For. Res. 3: 486-494. Dyer, E. D. A. 1975. Frontalin attractant in stands infested by the spruce beetle, Dendroctonus rufipennis (Coleoptera:Scolytidae). Can. Ent. 107: 979-988. Dyer, E. D. A. and J. A. Chapman. 1971. Attack by the spruce beetle induced by frontalin on billets with burrowing females. Can. For. Serv., Bi-Mon. Res. Notes 27: 10-11. Dyer, E. D. A. and L. Safranyik. 1977. Assessment of the impact of pheromone baited trees on a spruce beetle population. Can. Ent. 109: 77-80. Dyer, E. D. A. and D. W. Taylor. 1968. Attractiveness of logs containing female spruce beetles, Dendroc- tonus obesus. Can. Ent. 100: 769-776. Kinzer, G. W., A. F. Fentiman, Jr., T. F. Page, Jr., R. L. Foltz, J. P. Vite and G. B. Pitman. 1969. Bark beetle attractants; identification, synthesis and field bioassay of a new compound isolated from Den- droctonus. Nature 221: 447-478. Massey, C. L. and N. D. Wygant. 1954. Biology and control of the Engelmann spruce beetle in Colorado. U.S.D.A. Circ. No. 944. Siegel, S. 1956. Nonparametric Statistics for the Behavioral Sciences. McGraw-Hill Book Co. New York. 213 p. Wood, S. L. 1963. A revision of the bark beetle genus Dendroctonus Erickson (Coleoptera: Scolytidae). Gt. Basin Nat. 23: 117 pp. CBE STYLE MANUAL Fifth Edition A guide for Authors, Editors, and Publishers in the Biological Sciences Widely accepted and recommended as_ the standard reference for journals and books in the biological sciences Special features of this newly updated and greatly expanded edition include: ¢ four new chapters; © complete revision of the section * reorganization of the ‘‘Manuscript on ‘‘Plant Sciences’’; Preparation’’ section for easier ® cross-listing of ‘‘Abbreviations reference; and Symbols’’; ® new conventions in the chapter on “*Style in Special Fields’’; and much more... 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Maryland residents, please add 5% sales tax. Mail your order with payment to: COUNCIL OF BIOLOGY EDITORS, INC. 9650 Rockville Pike, Bethesda, MD 20814 90 J. ENTOMOL. Soc. Brit. COLUMBIA 80 (1983), DEc. 31, 1983 COURTSHIP AND MATING BEHAVIOR OF MEGASTIGMUS PINUS PARFITT (HYMENOPTERA:TORYMIDAE)! D. B. ORR AND J. H. BORDEN? Centre for Pest Management Dept. of Biological Sciences Simon Fraser University Burnaby, B.C. V5A 1S6 ABSTRACT The courtship and mating behavior of Megastigmus pinus Parfitt was observed in insect cages and under a dissecting microscope in petri dishes. Courtship had 6 components: a premounting rocking performance by the male; mounting by the male to a dorsal riding position on the female; antennation and abdominal and wing movement by the male; a series of forward lurches by the male; signaling of receptivity by the female, and subsequent movement of the male to position for copulation. The average durations of mounting and copulation were 6.76 min and 23.5 sec, respectively. Short courtship and copulation times may reduce the risk of predation. INTRODUCTION There are 23 species of Megastigmus (Hymenoptera: Torymidae) in North America, all of which are phytophagous (Milliron 1949). About half of them, mostly western, feed as larvae in con- ifer seeds (Keen 1958). Several species are serious pests. The larvae consume the entire contents of seeds leaving no external evidence of damage (Hedlin et al. 1980). The fir seed chalcid, Megastigmus pinus Parfitt, destroys the seed of Abies spp. from British Columbia, south to New Mexico (Keen 1958; Furniss and Carolin 1977; Hedlin et al. 1980). Little research has been done on the sexual behaviour of seed chalcids. Brief reports have described the courtship and mating behaviour of the Douglas-fir seed chalcid, M. spermotrophus Wachtl (Hussey 1955), M. brevivalvus Girault (No- ble 1938), and M. nigrovariegatus Ashmead (Milliron 1949). The objective of this study was to investigate in detail the courtship and mating behavior of M. pinus. METHODS AND MATERIALS Seeds of subalpine fir, Abies lasiocarpa (Hook.) Nutt., infested with M. pinus (9.3% infestation determined by radiography) were collected from Falkland, B.C., on September 1, 1981, and stored at approximately 0°C. Three lots were removed from refrigeration on August 16, 17 and 18, 1982, respectively, spread in emergence trays and kept outdoors. Adult emergence began August 26 and continued through September 19. Wasps were col- lected from emergence trays at 4 h intervals each ‘Research supported by Natural Sciences and Engineering Research Council of Canada Operating Grant A3881 and an Undergraduate Scholarship to D. B. Orr. Present address of D. B. Orr is Dept. of Entomology, Louisiana State University, Baton Rouge, LA 70803. Please send reprint re- quests to J. H. Borden. day from 0700 to 1900. They were segregated by sex and put in 50 x 35 x 35 cm cages placed well apart in an outdoor enclosure. Low ambient temperatures increased their average life span in accordance with Hussey’s (1955) observations. The insects were held at 20-23°C for at least 2 h prior to any observations. Complete observations of sexual behaviour in a 50 x 35 x 35 cm cage were made from September 3 to 5 between 0830 and 1330 in a windowed laboratory with constant fluorescent lighting. Observations were also made under a dissecting microscope of insects in a closed 60 x 20 mm disposable petri dish. Casual observa- tions were made whenever sexual behaviour was noticed in the laboratory and in storage cages. RESULTS AND DISCUSSION Courtship is initiated when a male and female pass within about 1 cm of one another. Males become agitated and increase their antennal activi- ty, then face the females, whereupon their antennae cease movement and straighten rigidly in front of their heads, parallel with one another. Parallel placement of the antennae also occurs during perception of host form and alignment by the braconid parasitoid, Coeloides brunneri Viereck, in which the elongate sensilla placoidea on the anten- nae apparently perceive infrared radiation from host larvae (Richerson and Borden 1972). If females are stationary, or remain within 1 cm, males begin rocking their bodies side to side from a fixed position similar to the premounting movement of M. spermotrophus (Hussey 1955) and numerous other chalcids (Assem 1974). The average duration of rocking behavior was 13 sec (Table 1). Many diurnal insects use movement, color and form in finding their mates (Engelmann 1968). Rocking prior to mounting apparently enhances visual acuteness (Assem 1974), but may also enhance heat perception of body form (Richerson and Borden 1972). J. ENTOMOL. Soc. BriIT. COLUMBIA 80 (1983), DEC. 31, 1983 9] FIGURE CAPTIONS Figs. 1-6. Schematic sequential representation of courtship and mating behaviour of Megastigmus pinus. Fig. 1, dorsal riding position assumed by male after rocking performance. Fig. 2, antennation and abdominal and wing movement by male. Fig. 3, beginning of “lurching” cycle by male in lower riding position with antennae extended to tip of female’s antennae. Fig. 4, male at most forward position in lurching cycle, with antennae curled backwards (insert). Fig. 5, receptive female with ex- posed genitalia detected by male. Fig. 6, position of male and female in copulo. 92 J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DEC. 31, 1983 After rocking, the male quickly mounts the female’s back either from the side or rear. If the female walks off during rocking the male may follow her for several centimetres and resume his performance if he gets within 1 cm of her again. Once mounted, males assume a dorsal riding position (Fig. 1), front tarsi resting on the female’s head, the middle pair on the metathorax and hind tarsi grasping the anterior edges of the female’s fold- ed wings. This courting position is also used by M. spermotrophus (Hussey 1955) and other chalcids, such as the Pteromalinae (Assem and Povel 1973). Almost immediately after mounting, the male begins tapping and stroking the female’s antennae with his own, and his abdomen starts vibrating (Fig. 2). Occasionally he may fan his wings with his abdomen raised. Wing fanning was also observed in M. nigrovariegatus but only in conjunction with a forward surge by the male (Milliron 1949). In M. pinus these 2 activities are distinct. About 29 sec after mounting, the male assumes a lower, slightly forward position, touching the tips of the female’s antennae with his own (Table 1, Fig. 3). The male then makes a smooth, forward and slightly downward lurch until his head is just past the distal ends of the female’s antennae (Fig. 4). His head moves forward between and just above the female’s antennae, which are lowered at the same time the male lurches. From here, he immediately returns to the normal courting position, thus com- pleting one lurching cycle. This cycle is repeated about 15 times in sequence over approximately 26 sec; there are approximately 5 lurching se- quences/courtship (Table 1). When the male moves forward, his antennae curl behind his head (Fig. 4), but do not contact the basal joints of the female’s antennae as in M. spermotrophus (Hussey 1955). TABLE I. Quantitative measures of each component of courtship and mating behaviour in Megastigmus pinus. Activity* Range Mean + Standard Deviation Duration of rocking 4 - 33 13-2 Wd6 performance (sec) Time from mounting to first 130-54 28.6% =. 16a7 "lurching" sequence** (sec) Number of "lurching" 3-9 5.4 = Zeal sequences/mat ing Duration of “lurching” Sray45 26322105 sequences (sec) Number of "lurches" 6 - 23 14.6 += 4.80 per sequence Frequency of "lurching" 27 ae 1,78 £ “0.73 (lurches/sequence) Time in copulo (sec) 16 - 33 23.5 2) le Total time mounted (min) eos age as) 6.76 2. 2.38 observations from 5 pairs of insects. * ** one sequence consists movements. of one continuous series of "lurching" J. ENTOMOL. Soc. BriT. CoLuMBIA 80 (1983), DEc. 31, 1983 23 Lurching behavior has been observed in M. spermotrophus (Hussey 1955), M. nigrovariegatus (Milliron 1949) and M. brevivalvuus (Noble 1938) as well as other chalcids (Assem and Povel 1973). However, each species has distinct differences in amplitude, speed and length of movements. Similar examples of variation in courtship movements occur in widely divergent taxa, and include variations in leg movements by displaying fiddler crabs (Crane 1957, 1966) and head and body movements in displaying lizards (Hunsaker 1962; Purdue and Carpenter 1972). Such differences in specific court- ship pattern can provide ethological isolating mechanisms which prevent hybridization between closely related sympatric species (Solbrig and Solbrig 1979). During lurching, M. spermotrophus males do not move as far forward as do M. pinus males, only bringing the head of the male in contact with the female’s (Hussey 1955). Observations under a dissecting microscope revealed that the mandibles of M. pinus males do not actually touch the head or antennae of the female, as Milliron (1949) has observed in M. nigrovariegatus. The lurching performance by M. pinus males apparently makes females receptive to mating. Dur- ing the last lurching cycle performed by the male, the female raises her abdomen, thus exposing her genital aperture. This postural change is indicative of female receptivity in chalcids, and is usually coupled with characteristic antennal and head posi- tion changes which provide a secondary signal to the male (Assem 1974). Neither of these latter signals was observed in M. pinus. When the M. pinus male detects the female’s receptivity (Fig. 5) he quickly turns around and moves into position for copulation (Fig. 6). In con- trast, male M. spermotrophus (Hussey 1955) and M. nigrovariegatus (Milliron 1949) move backwards in- to position for copulation. Copulation lasts about 24 sec (Table 1), a much shorter period than in some other insects such as the meloid beetle, Lytta nut- talli Say, which copulates for 8 to 10 h (Gerber 1973). M. pinus males sometimes remounted females directly from the in copulo position, and repeated their entire courtship behavior, ter- minating in copulation. One M. pinus pair was observed to copulate 4 times in succession. Similariy repeated courtship also occurs in M. nigrovariegatus, but does not result in multiple copulations (Milliron 1949). Short courtship and copulation periods may be selectively advantageous to M. pinus. In nature, Megastigmus spp. copulate on host foliage. The longer a pair remains in copulo, the greater the risk of exposure to enemies or to unmated males which may harass the copulating pair, thereby drawing the attention of predators (Richards 1927). The activity of M. pinus males throughout courtship and mating was noticeably aggressive, whereas females appeared passive once mounted. Unmated males were apparently attracted to mating pairs and sometimes performed a rocking display. Interfering males sometimes mounted the back of an already mounted male, or displaced another male from a female. Interference of mating pairs by unmated males has been observed in other insect species including the striped ambrosia beetle, Trypodendron lineatum Olivier (Fockler and Borden 1972) and the alfalfa weevil, Hypera postica (Gyllenhal) (LeCato and Pienkowski 1970a). Homosexual behavior of M. pinus males was noticed in the presence and absence of females. Males performed rocking displays before mounting other males. These mounted males were sometimes in turn mounted by other males. Males of other in- sect species which have been observed to display homosexual activity include T. lineatum (Fockler and Borden 1972), H. postica (LeCato and Pienkowski 1970a) and the grasshopper, Aulocare elliotti (Thomas) (Ferkovich et al. 1967). The apparent high degree of sexual tension pre- sent in the insects studied may have represented maximum sexual activity brought about by crowd- ed conditions and previous isolation of the sexes, as occurs in H. postica (LeCato and Pienkowski 1970b). However, the intricate, stereotyped court- ship behavior with multiple mating by a single pair represents a highly evolved, species specific behavior well adapted to ensure reproductive success. ACKNOWLEDGEMENTS We thank R. H. Heath, D. S. Ruth, D. W. Taylor and Drs. D. G. W. Edwards and G. E. Miller for their advice and assistance. REFERENCES Assem. J. Van Den. 1974. Male courtship patterns and female receptivity signals of Pteromalinae. Neth. J. Zool. 24: 253-278. Assem, J. Van Den and G. D. E. Povel. 1973. Courtship behaviour of some Muscidifurax species (Hym., Pteromalidae): a possible example of a recently evolved ethological isolating mechanism. Neth. J. Zool 23: 465-487. Crane, J. 1957. Basic patterns of display in fiddler crabs (Ocypodidae, Genus Uca). Zoologica 42: 69-82. _______. 1966. Combat, display and ritualism in fiddler crabs. (Ocypodidae, genus Uca). Phil. Trans. Roy. Soc. London B 251: 459-472. Engelmann, F. 1968. The physiology of insect reproduction. Pergamon Press, New York. 24 J. ENTOMOL. Soc. BriT. COLUMBIA 80 (1983), DEc. 31, 1983 Ferkovich, S. M., S. G. Wellso, and W. T. Wilson. 1967. Mating behavior of the bigheaded grasshopper, Aulocara elliotti (Orthoptera: Acrididae) under caged conditions in the greenhouse and outdoors. Ann. Entomol. Soc. Amer. 60: 972-975. Fockler, C. E. and J. H. Borden. 1972. Sexual behavior and seasonal mating activity of Trypodendron lineatum (Coleoptera: Scolytidae) Can. Entomol. 104: 1841-1853. Furniss, R. L. and V. M. Carolin. 1977. Western forest insects. USDA, For. Serv. Misc. Publ. 1339. Gerber, G. H. and N. S. Church. 1973. Courtship and copulation in Lytta nuttalli (Coleoptera: Meloidae). Can. Entomol. 105: 719-724. Hedlin, A. F., H. O. Yates III, D. C. Tovar, B. H. Ebel, T. W. Koerber and E. P. Merkel. 1980. Cone and seed insects of North American conifers. Environ. Canada, Can. For. Serv., Ottawa; USDA, For. Serv., Washington, D.C.; Univ. Autonoma Chapingo, Chapingo, Mexico. Hunsaker, D. 1962. Ethological isolating mechanisms in the Sceloporus torquatus group of lizards. Evolu- tion 16: 62-74. Hussey, N. W. 1955. The life-histories of Megastigmus spermotrophus Wachtl (Hymenoptera: Chalcidoidea) and its principal parasite, with descriptions of the developmental stages. Trans. Roy. Entomol. Soc. Lond. 106 Pt. 2: 133-151. Keen, F. P. 1958. Cone and seed insects of western forest trees. USDA, For. Serv., Tech. Bull. 1169. LeCato, G. L. III and R. L. Pienkowski. 1970a. Laboratory mating behavior of the alfalfa weevil, Hypera postica. Ann. Entomol. Soc. Amer. 63: 1000-1007. . 1970b. Sexual responsiveness of the male alfalfa weevil, Hypera postica, as affected by prior con- tact with other alfalfa weevils. Entomol. Exp. & Appl. 13: 462-466. Milliron, H. E. 1949. Taxonomic and biological investigations in the genus Megastigmus with particular reference to the taxonomy of the Nearctic species (Hymenoptera: Chalcidoidea: Callimomidae). Amer. Midl. Nat. 41: 257-420. Noble, N. S. 1938. Epimegastigmus (Megastigmus) brevivalvus Girault: a parasite of the citrus gall wasp (Eurytoma fellis Girault): with notes on several other species of hymenopterous gall inhabitants. Dept. Agr., N.S. Wales, Sci. Bull. 65: 5-46. Purdue, J. R. and C. C. Carpenter. 1972. A comparative study of the body movements of displaying males of the lizard genus Sceloporus (Iguanidae). Behaviour 41: 68-81. Richards, O. W. 1927. Sexual selection and allied problems in insects. Biol. Rev. 2: 298-364. Richerson, J. V. and J. H. Borden. 1972. Host finding by heat perception in Coeloides brunneri Viereck (Hymenoptera: Braconidae). Can. Entomol. 104: 1877-1881. Solbrig, O. T. and D. J. Solbrig. 1979. Introduction to population biology and evolution. Addison-Wesley Publ. Co., Reading, Massachusetts. J. ENTOMOL. Soc. Brit. COLuMBIA 80 (1983), DEc. 31, 1983 25 TETRASTICHUS GALACTOPUS (HYM.:EULOPHIDAE), A HYPERPARASITE OF APANTELES RUBECULA AND APANTELES GLOMERATUS (HYM.:BRACONIDAE) IN NORTH AMERICA VINCENT G. NEALIS Institute of Animal Resource Ecology and Department of Plant Science, University of British Columbia Vancouver, British Columbia 2075 Wesbrook Mall, Vancouver, B.C. ABSTRACT The biology of Tetrastichus galactopus, a hyperparasite of Apanteles rubecula and A. glomeratus in North America, is reviewed. The female hyperparasite at- tacks its hosts while they are larvae in their primary host, Pieris rapae, although free-living cocoons of A. glomeratus may also be attacked. In Vancouver, where A. rubecula is the only available host, T. galactopus is active from July through September and probably overwinters as a pupa or adult within the host cocoon. The significance of hyperparasitism to the success of biological control efforts using Apanteles is discussed. INTRODUCTION Tetrastichus glactopus (Ratzburg) is a gregarious eulophid hyperparasite of braconid lar- vae. In Europe, it has been commonly reared from Apanteles glomeratus (L.) parasitizing Pieris brassicae (L.), the large cabbage white. It is a true hyperparasite, depositing several eggs through the primary host directly into the larval stage of its own host (Picard 1921). Ferriére and Faure (1925) observed oviposition through newly spun cocoons of A. glomeratus but thought a different species of hyperparasite was involved. This view, although not supported by morphological evidence (Delucchi 1950), has contributed to taxonomic confusions; Tetrastichus rapo Walker is the most common synonym in the literature (Krombien et al. 1979). Picard (1921). Gautier and Bonnamour (1924) and Richards (1940) reported hyperparasitism by T. galactopus of Apanteles rubecula Marshall, a solitary parasite of the imported cabbageworm, Pieris rapae (L.). Both A rubecula and A. glomeratus attack early instar P. rapae larvae, emerge from the fourth and fifth instars respective- ly, and spin a pupal cocoon. The former parasite normally lays one egg to produce a single larva; the latter lays thirty to sixty eggs at a time in each host. T. galactopus must have entered North America with A. glomeratus which has been wideiy distributed for biocontrol of P. rapae. In British Columbia, T. galactopus attacks A. rubecula (Wilkinson 1966). Where releases of A. rubecula have been made in areas formerly inhabited by A. glomeratus only, local T. galactopus parasitize the progeny of the released A. rubecula (Parker et al. 1971), During 1981-82, I made several collections of T. galactopus from A. rubecula in the lower mainland of British Columbia and established colonies using both A. rubecula and A. glomeratus stocks. A. glomeratus is available in the Okanagan Valley but it has not been collected around Vancouver. It is not known if T. galactopus is also in the Okanagan. This paper reports field and laboratory data and reviews the biology of T. galactopus. MATERIALS AND METHODS Field collections made during 1981-82 were from two sites in the Vancouver area. One was a co- operative garden plot allotment near the Fraser River in Burnaby (BBY), which had been one of Wilkinson’s (1966) original sites; the other site was an isolated research plot of less than 100 plants, on the Plant Science Field Station at the University of British Columbia (UBC). From both sites in 1981 and at BBY in 1982, P. rapae larvae were brought to the laboratory, separated by instar and reared on potted kale. If Apanteles emerged from the cater- pillars, the cocoons were weighed and kept in- dividually in gelatin caps at 22°C and a 16L:8D photoperiod. Apanteles cocoons collected in the field were treated similarly. In 1982 A. rubecula reared at UBC for diapause studies were an addi- tional data source. These primary parasites were allowed to emerge from the host caterpillar and spin a cocoon in the field, then collected and held at 22°C. and a 16L:8D photoperiod. T. galactopus that emerged from these cocoons were sexed and counted. This technique measured the density and sex ratio of T. galactopus per A. rubecula cocoon and permitted estimates of parasitism rates accor- ding to the age of the primary host, through the season. Adult T. galactopus live several weeks at low temperatures if water and honey are available. I kept adults in styrofoam cup-cages and exposed A. rubecula and A. glomeratus to them as cocoons and at various stages within their host larvae. I was thus able to observe the oviposition behaviour of T. galactopus. I also exposed non-parasitized cab- bageworms to T. galactopus as well as final instar A rubecula that had experienced a pre-treatment that would induce diapause i.e. less than 14 h photophase. Some Apanteles were exposed to un- 96 J. ENTOMOL. Soc. BriT. COLuMBIA 80 (1983), DEc. 31, 1983 TABLE 1. Number and per cent parasitism of Apanteles rubecula by Tetrastichus galactopus according to the stage in which the primary host (Pieris rapae) was collected. Data pooled from all collections BBY, 1981 and 1982. _——————————————————— el HOST STAGE COLLECTED PARASITES Pieris rapae III 124 IV 352 A fubécula cocoons 94 Apanteles rubecula Tetrastichus galactopus (%) 9 7,2) 132. G7.5) 37° (39), 3) a mated female T. galactopus to determine the sex of haploid progeny. Attacked larvae were reared in- dividually on plants or, in cases where I intended only to confirm oviposition, were dissected undersaline. RESULTS AND DISCUSSION My observations confirm earlier studies that T. galactopus attacks both A. rubecula and A. glomeratus while they are inside the primary cab- bageworm host. Although oviposition is normally directly into the primary parasite, a few eggs were found in the caterpillar’s body cavity. It is unlikely that these eggs can develop and eventually enter the appropriate host (Richards 1940). Picard (1921) described T. galactopus attacking non-parasitised P. rapae but eggs were never found in the body cavity. I observed T. galactopus inserting their ovipositors through the body wall of several non- parasitised P. rapae but only once were eggs found in the dissected caterpillars. Oviposition must re- quire a further stimulus provided only by the presence of a primary parasite. Most parasitism of A. rubecula by T. galactopus occurs when the cabbageworm is in the fourth in- star, that is, when A. rubecula is close to emergence (Table 1). In laboratory trials, A. rubecula, one- quarter and midway through the total parasitic period, were exposed to T. galactopus. The results showed that successful parasitism of A. rubecula was unlikely before the second instar and in most cases not until a few days before emergence. I have never succeeded in obtaining parasitism of A rubecula after the larva has emerged from the primary host and spun a cocoon. T. galactopus walks over A. rubecula cocoons but does not oviposit. The silk may be too dense to permit inser- tion of the ovipositor. In comparison, T. galactopus parasitizes A. glomeratus either through the primary host or after the free-living cocoon is form- ed but before pupation of the primary parasite. All individuals in a cluster are not necessarily attacked. The number of T. galactopus emerging from one host cocoon varies widely. More emerge from A. rubecula cocoons (10.6+ 0.89 hyperparasites per cocoon; range 1-21) than from the smaller cocoons of A. glomeratus (4.3 + 0.52 hyperparasites per co- coon; range 2-7). The highest hyperparasite den- sities may be due to superparasitism as more than one T. galactopus is often seen on a single primary host in the field. The data relating the density of T. galactopus to the weight of A rubecula show that host size does not significantly influence parasite density (r = 0.142; df = 52). Rather, a high hyper- parasite density per host leads to a smaller average size as has been shown for other gregarious parasites (Bouletreau 1971). Mature T. galactopus larvae bite emergence holes through the host body wall but remain within the host cocoon to pupate. Adults emerge over a pro- tracted period, through one to several holes in the host cocoon. What appears to be a strong positive phototaxis results in rapid dispersal of these adults. T. galactopus is arrhenotokous; unmated females produced only male progency. Most field collected parasitized A rubecula yielded both sexes of adult T. galactopus; only a small proportion were all female (10.5%) or all male (6.6%). Nevertheless, the sex ratio in the collections after August was always skewed in favour of females and varied through the remainder of the season (Figure la). Richards (1940) also found a preponderance of female T. galactopus in field samples. When A. rubecula were reared under field or laboratory conditions that normally induced diapause and were used as hosts of T. galactopus, the hyperparasite developed continuously. It is not known if there is a true diapause in T. galactopus but if so, it seems from these observations that it is independent of the host’s response to environmental conditions. In Europe, T. galactopus is widely distributed over the range of A. glomeratus, parasitizing over 50% of the available larvae at some times of the year (Mook and Haeck 1965; Richards 1940). There J. ENTOMOL. Soc. BrIT. COLUMBIA 80 (1983), DEc. 31, 1983 at % FEMALES (95% C.l.) % PARASITISM May June July Aug Sept Oct nes 1. a /aCtOD US G.: oes A. UDC CU EEE ELE 5 6 i ae Fig. 1. Phenology of Tetrastichus galactopus at two locations in British Columbia during 1982 (BBY- Burnaby; UBC-University of British Columbia). a) Per cent female T.galactopus at BBY. b) Per cent parasitism of A. rubecula (ex IV-instar P.rapae + cocoons only) by T.galactopus at BBY and UBC. c) Seasonal activity schedule for adult P.rapae, A.rubecula and T.galactopus in the Vancouver area. are a few estimates for A. rubecula from North America. When A. rubecula was released in Missouri, hyperparasitism by T. galactopus ranged from 36.6% to 72.4% (Parker et al. 1971). At BBY, hyperparasitism of A. rubecula reached 62% in 1981 and 41% in 1982. Comparable levels were observed at UBC in 1982. Except for the relatively late start of the UBC population, the same seasonal pattern was evident at both study sites (Fig 1b). Parasites often lag behind their hosts in spring ap- pearance (compare P. rapae and A. rubecula in Figure lc). In the case of T. galactopus, the lag may be due to a sustained diapause through the spring or a high winter mortality and perhaps frequent local extinction with subsequent slow recolonization of the sample areas. Mook and Haeck (1965) thought dispersal of T. galactopus was rapid, an impression consistent with T. galactopus finding the isolated cohorts at UBC; but the evidence is circumstantial. The occurence of T. galactopus in the earliest col- lections at BBY make it arguable that the hyper- parasites are highly synchronized with the first generation of the primary parasite and that the ap- parent time lag is due to previous local extinctions in that area. It is difficult to ascertain the effects of hyper- parasitism on populations of either A. glomeratus or A. rubecula. Blunck (1957) states that hyper- parasites in Germany “diminish the useful effect of A. glomeratus” but offers no data. Parker et al. (1971) did not think the “sizeable loss of A. rubecula to hyperparasites throughout the season” affected its role in suppression of P. rapae populations. But it is true that A. rubecula has failed to become establish- 98 J. ENTOMOL. Soc. BRIT. CoLuMBIA 80 (1983), DEc. 31, 1983 ed at their release sites in Missouri where hyper- parasitism by T. galactopus was common. However A. rubecula’s persistence in Vancouver despite ap- preciable hyperparasitism by T. galactopus argues against hyperparasitism as a predominant limita- tion to establishing A. rubecula in North America. ACKNOWLEDGEMENTS All laboratory work was carried out at the Van- couver Research Station, Agriculture Canada. I thank B. D. Frazer for research space and review of the manuscript, and A. T. S. Wilkinson for advice. C. Yoshimoto of the Biosystematics Research In- stitute, Ottawa confirmed my determination of Tetrastichus galactopus. REFERENCES Blunck, H. 1957. Pieris rapae (L.), its parasites and predators in Canada and the United States. J. Econ. Entomol. 50:835-836. Bouletreau, M. 1971. Métabolisme respiratoire de Pteromalus puparum (Hym, Chalc.) au cours du développement et influence de la densité de population larvaire. Ann. Zool. Ecol. Anim. 3:195-207. Delucchi, V. 1950. Note morfologiche su Tetrastichus rapo Walker ,Chalcidide parassita di Imenotteri utili allagricoltura. Redia 35:441-450. Ferriére, C. and J. C. Faure. 1925. Contribution a l’étude des Chalcidiens parasites de |’ Apanteles glomeratus, L. Ann. Epiphytes 11:221-234. Gautier, C. and S. Bonnamour. 1924. Recherches sur Tetrastichus rapo, (Hym. Chalcididae). Rev. Path. Veg. & Ent. Agric. 11:246-253. Krombien, K. B., P. D. Hurd, Jr., D. R. Smith and B. D. Burks. 1979. Catalog of Hymenoptera in America North of Mexico. Vol. I Smithsonian Institution Press, Washington, D.C. 1198pp. Mook, J. H. and J. Haeck. 1965. Dispersal of Pieris brassicae L. (Lepidoptera:Pieridae) and of its primary and secondary hymenopterous parasites in a newly reclaimed ploder of the former zuiderzee. Ar- chiv. Neerlandaises de Zoologie 16:293-312. Parker, F. D., F. R. Lawson and R. E. Pinnell. 1971. Suppression of Pieris rapae using a new control system: mass releases of both the pest and its parasites. J. Econ. Entomol. 64:721-735. Picard, F 1921. Sur la biologie du Tetrastichus rapo Walk. (Hym. Chalcididae). Bull. Soc. Ent. Fr. 9:206-208. Richards, O. W. 1940. The biology of the small white butterfly (Pieris rapae), with special reference to fac- tors controlling its abundance. J. Anim. Ecol. 9:243-288. Wilkinson, A. T. S. 1966. Apanteles rubecula Marsh and other parasites of Pieris rapae in British Columbia. J. Econ. Entomol. 59:1012-1013. J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DEc. 31, 1983 MICROORGANISMS ISOLATED FROM FOREST INSECTS OF BRITISH COLUMBIA O.N. MORRIS! Forest Pest Management Institute Canadian Forestry Service Sault Ste. Marie, Ontario P6A 5M7 ABSTRACT Pathogenic and non-pathogenic microorganisms including fungi, bacteria, viruses, miscrosporidia and nematodes were isolated from about 14,000 specimens representing 108 pest species of insects collected from British Columbia forests bet- ween 1949 and 1969. Entomophthora sp. and Beauveria sp were the most widely distributed fungal organisms isolated, occurring in 14 and 29 insect species, respec- tively. Nuclear polyhedrosis and granulosis viruses were isolated from 53 species, microsporida from 26, pathogenic bacteria from 12 and nematodes from 2 species. A new variety of Bacillus thuringiensis, viz. canadensis, was isolated from Lamb- dina fiscellaria lugubrosa (Hlst.) and a Neophasia sp. The largest numbers of species of microorganisms were found in Melanolophia imitata (Wlk.), Malacosoma disstria Hbn., M. pluviale (Dyar), L. f. lugubrosa, Acleris variana (Fern.), Hyphantria cunea Dru., Choristoneura fumiferana (Clem), Orgyia pseudotsugata (McD) and Neophasia menapia Feld. INTRODUCTION The concept of pest management involves the ra- tional utilization of a variety of biotic and abiotic agents in a well-planned strategy against agricultural and forest insect pests. The naturally occurring microbial control agents can form an im- portant component of such strategies and, indeed, their use presently constitutes a highly advanced alternative to chemical pesticides. However, prior to introducing microbial control agents into a stable forest ecosystem it is essential, for several reasons, that an inventory of the natural enemies of the pest species be taken. Firstly, native biocontrol agents can have devastating effects on the insect popula- tions and their isolation, characterization and manipulation could form part of the management program. Secondly, man-made_ intervention schemes may not always be compatible with natural biotic schemes already operating in the en- vironment. Finally, the development of simulation models for pest management presupposes a knowledge of the pest’s population dynamics which should include key factor analysis of the natural enemy complexes. An insect disease survey was initiated in 1949 in the forests of British Columbia by the late S. M. Sagar, and continued between 1960 and 1969 by the author. This paper summarizes the results of that survey and, with the possible exception of a similar survey in Quebec (Smirnoff and Juneau, 1973), con- stitutes the most extensive and detailed documenta- tion of microorganisms found in forest insects from a single geographic area in Canada. MATERIAL AND METHODS Dead insects, collected by laboratory staff during ‘Present Address: Agriculture Canada Research Station, 195 Dafoe Road, Winnipeg, Manitoba R3T 2M9. the annual insect and disease surveys, were submit- ted in plastic pill capsules to the Pacific Forest Research Centre and were stored at 4°C until ex- amined for microorganisms. In cases of widespread viral epizootics, large numbers of cadavers were sent collectively to allow for purification of the pathogen for study beyond simple light miscroscopy identification. Cadavers with external symptoms of fungal infec- tions were sent directly to the Insect Pathology Research Institute (IPRI), Sault Ste. Marie, On- tario, for identification of the pathogen. Wet mounts of cadavers in which fungal spores, conidia or other development elements were found were isolated on potato-dextrose agar or Sabouraud’s medium and sent to IPRI. Occasionally, fungal specimens were identified by the Insect Disease Diagnostic Laboratory, University of California, Berkeley. Insect specimens were considered positive for virus infection only if virus inclusion bodies were observed in susceptible tissue sites (fat body, hypodermis, tracheal matrix, hemocytes and gut epithelium). In a few cases, when sufficient material was available, nuclear polyhedrosis virus inclusion bodies were purified by differential cen- trifugation, processed for transmission electron microscopy, and sectioned to reveal the capsid nature of the virus. Suspected cases of microsporidial infections were either fixed to glass slides and stained with Giemsa to observe the characteristic differential staining of regions of the spore, or pressure was applied to a cover slip above a wet smear to facilitate the extru- sion of polar filaments. The identification of proto- zoan parasites was limited to the Order Microsporidia. 30 J. ENTOMOL. Soc. BriIT. COLUMBIA 80 (1983), DEc. 31, 1983 Most bacteria found in insects are saprophytic aerobic species which may cause lethal septicemia upon entering the hemocoel. Because nearly all the insect species examined during the present survey contained saprophytic or pathogenic bacteria and since time and resources did not allow for identify- ing all bacterial isolates, only those in which spores, or spores and crystals were present in squashed preparations were identified to species. Eighteen isolates were eventually identified, using reaction to Gram stain, cellular morphology, colony type, slant form, broth form, oxygen requirements, temperature requirements, growth on special media (motility medium, blood agar, NaCl broth) and biochemical reactions. The latter included fermen- tation reactions in glucose, lactose, maltose, sucrose, xylose, mannitol, arabinose, cellobiose, fructose, galactose, mannose, raffinose, rhamnose, trehalose, dulcitol, inositol, sorbitol, dextrin, in- ulin, salicin, starch and levulose. Other biochemical reactions were gelatin liquefaction, indol produc- tion, Nitrate reduction, litmus milk, methyl red, HS production, V.P. test, urea slant (ammonia), citrate agar, citrate broth, phospholipase C, and ca- sein hydrolysis. On this basis, a preliminary iden- tification of the bacterial species was made, and slant cultures were sent to Dr. H. de Barjac, Institut Pasteur in Paris for species confirmation and serotyping. A total of about 14,000 specimens representing 108 insect species were examined dur- ing the 20-year survey periods. The number of distinct locations and the year in which the microorganisms were found are listed in Table 1, indicating geographical distribution and frequency of occurrence. The complexes of microorganisms isolated from the most important economic pests are given in Table 2. TABLE 1. Microorganisms isolated from forest insects of British Columbia. Number of Pathogens Hosts Locations Years FUNGI Entomphthora* Melanolophia imitata (Wlk.) 31 1949, 1950, 1953, 1956, 1957, 1958, 1965, 1967 Nyctobia limitaria nigroangulata Stkr. 1 1956 Ectropis crepuscularia Schiff. 1 1950, 1951 Caripeta divisata (Wlk.) 3 1950 Lambdina fiscellaria lugubrosa (Hulst.) 6 1947, 1949, 1950, 1951, 1953, 1956, 1967 Malacosoma pluviale (Dyar) 1 1956 Nematocampa filamentaria Gn. ] 1954 Griselda radicana Wlshm. I 1954 Acleris variana (Fern.) Z 1956 Nypetia phantasmaria (Strk.) ] 1957 Anthelia hyperborea (Hbst.) 1 1956 Pikonema dimmockii (Cress.) 1 1954 Arge pectoralis (Leach) ] 1953 Neodiprion tsugae (Midd.) 3 1954, 1957 Beauveria (globilifera (Speg.)* Choristoneura fumiferana (Clem.) 5 1950, 1951 Malacosoma pluviale (Dyar) fi 1957, 1958 Dendroctonus obesus (Mann) ] 1968 Beauveria bassiana (Bals.)* Venusia cambrica Cur. 1 1950 Malacosoma pluviale (Dyar) re 1957, 1958 Dendroctonus obesus (Mann) : 1968 Beauveria sp. * Lambdina fiscellaria lugubrosa (Hst.) 2 1953, 1954 L. f. somniaria (Hlst.) l 1949 Epirrita autumnata (Gn.) 1 1949 Campaea perlata (Gn.) 1 1949 Enypia venata (Grt.) 3 1949, 1953 Enypia packardata Taylor 1 1953 Feralia jacosa (Gn.) 1 1958 Stilpnotia salicis (L.) 1 1956 Syngraphia alias interalia Ott. 1 1953 Trichiosoma triangulum Kyb. 4 1951, 1957 Orgyia pseudotsugata (McD) 1 1958 J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DEc. 31, 1983 TABLE lI. (cont'd) Microorganisms isolated from forest insects of British Columbia. Pathogens Cephalosporium sp. Penicillium sp. Verticillium sp.* Fusarium sp.* Alternaria sp. Spicaria sp.* Hirsutella sp.* Cordyceps sp.* Aspergillus sp. Harmodendrum sp. Trichosporon sp. VIRUS Baculovirus (Nuclear Poly- hedrosis virus subgroup) (NPV) Hosts 31 Number of Locations Archips cerasivorana Fitch Epicnaptera americana Harr. Pseudohazia eglanterina (Bdv.) Malacosoma disstria Hbn. Halisidota argentata Pack. Apantesis parthenia Kby. Choristoneura fumiferana (Clem.) Cephalcia sp. Tolype sp. Neodiprion tsugae Midd. Hemichroa crocea (Fourc.) Pityophagus rufipennis Hom. Epirrita autumnata (Gn.) Campaea perlata (Gn.) Syngrapha alias interalia Ott. Adelges piceae (Ratz.) Eupithecia filmata Pears Pikonema sp. Malacosoma pluviale (Dyar) Melanolophia imitata (Wlk.) Neodiprion tsugae Midd. Adelges piceae (Ratz.) Lambdina fiscellaria somniaria (Hlst.) Microlepidoptera Melanolophia imitata (W\k.) Smerinthus cerisyi Kby. Malacosoma pluviale (Dyar) Hemichroa crocea (Fourc.) Neodiprion sp. Malacosoma pluviale (Dyar) Zale duplicata largera Sm. Malacosoma pluviale (Dyar) Acleris variana (Fern.) Cephalcia sp. Nictobia limitaria nigroangularia Strk. Melanolophia imitata (Wlk.) Malacosoma pluviale (Dyar) Acleris variana (Fern) Melanolophia imitata (Wlk.) Melanolophia imitata (Wlk.) Lambdina fiscellaria lugubrosa (Hlst.) Nepytia phantasmaria (Stkr.) Melanolophia imitata (W\k.) Malacosoma disstria Hbn. Lambdina fiscellaria somniaria (Hlst.) Choristoneura fumiferana (Clem.) Ectropis crepuscularia Schiff. Malacosoma pluviale (Dyar) wo >} We Years 1954, 1957 1949 1957 1954 1954 1954 1957 1949 1957 1949, 1954 1949 1957 1949 1949 1949 1965 1967 1967 1953, 1957 1951, 1965 1950, 1951 1965 1965 1965 1949 1949 1956 1949 1949 1956 1957 1956 1957 1967 1950 1961 1965 1967 1967 1968 1947, 1954, 1956, 1950, 1960, 1951, 1962, 1948 1960, 1950, 7 1949, 1956 1957 1951, 1961, 1953, 1968, 1949, 1961, 1968, 1951, 1953, 1957, 1958, 1965, 1969 1954, 1957, 1969 1951, 1958, 1962 1969 1960, 1961, 1962, 1965, 1969 1953, 1956, 1957, 1958, 32 Pathogens (Granulosis virus subgroup) (G.V.) J. ENTOMOL. Soc. Brit. COLUMBIA 80 (1983), Dec. 31, 1983 Hosts Enypia venata Grt. Hydriomena nubilofasciata Pack. Hydriomena irata Sw. Pero mizon Rindge Pero behrensarius Pack. Euthyatira pudens Gn. Feralia jacosa Gn. Orthosia hibisci Gn. Stilpnotia salicis L. Synaxis pallulata (Hlst.) Synaxis jubararia (Hlst.) Syngrapha selecta (Wlk.) Nyctobia limitaria nigroangulata Stkr. Erranis vancouverensis (Hlst.) Orgyia pseudotsugata (McD.) Nymphalis antiopa L. Caripeta divisata (Wlk.) Hesperumia sulphuraria Pack Protoboarmia indicataria (W1k.) Hyperetis amicaria H & S Dyoryctria pseudotsugella Monroe Halisidota argentata Pack Acleris variana (Fern.) Panthea portlandia Gtrt. Orgyia antiqua badia (Hy. Ed.) Polygonia satyrus Ed. Operophtera bruceata (Hst.) Eupithecia sp. Neodiprion tsugae Midd. Neodiprion abietis (Harr.) Hemichroa crocea (Fourc.) Neodiprion sp. Eupithecia annulata (Hst.) Zeiraphera pseudotsugana Kft. Pikonema dimmockii (Cress.) Vanessa cardui Dyar Neophasia menapia Feld Tetropium cunnamopterum Kirby Papilio daunis Bdv. Hyphantria cunea (Drury) Lambdina fiscellaria lugubrosa (Hlst.) Lambdina fiscellaria somniaria (Hlst.) Malacosoma pluviale (Dyar) Acleris variana (Fern.) Pseudohazia eglanterina (Bdv.) Griselda radicana W\shm. Nematocampa filamentaria Gn. Sciaphila duplex Wlshm. Clepsis persicana (Fitch.) Hyphantria cunea (Drury) Arge pectoralis (Leach) TABLE 1. (cont'd) Microorganisms isolated from forest insects of British Columbia. Number of Locations Years RPeuwdeDpe Dorner rwon ONNHKHENYN WNNHE Eee ies) oe) = | PO ES i = DO eS eS DO Ow 1961, 1962, 1963, 1965, 1966, 1967, 1968, 1969 1949 1950 1950 1953 1956 1949 1949, 1950 1949, 1950 1956, 1958, 1962, 1969 1951, 1954 1956 1957 1950, 1965 1958 1954, 1958, 1961, 1969 1956, 1968 1952, 1961 1949 1949 1957 1962, 1966 1961, 1968 1965, 1962, 1954, 1956, 1957, 1960, 1965, 1966, 1967, 1968 1953 1954, 1956 1956 1957 1956, 1965 1950, 1956, 1957 1957 1950 1950, 1954, 1956, 1957, 1965 1965 1965 1965 1966 1968 1968 1968 1969 1947, 1953 1948 1953, 1956 1953, 1954 1953 1954 1954 1957 1957 1949, 1969 1954 J. ENTOMOL. Soc. Brit. COLUMBIA 80 (1983), DEC. 31, 1983 83 TABLE 1. (cont’d) Microorganisms isolated from forest insects of British Columbia. Number of Pathogens Hosts Locations Years PROTOZOA Microsporidia Choristoneura fumiferana 6 1950, 1954, 1968, 1969 Choristoneura conflictana ] 1957 Acleris variana (Fern.) 8 1953, 1956, 1966, 1968 Sciaphila duplex Wlshm. ] 1957 Malacosoma pluviale Dyar 3 1965, 1967, 1969 Malacosoma disstria Hbn. 2 1968, 1969 Melanolopia imitata Dyar i 1965, 1969 Eupithecia filmata Pears ] 1965 Orthosia hibisci Gn. ] 1965 : Nyitobia limitaria nigroangulate Stkr. 4 1965, 1966 Lambdina fiscellaria lugubrosa Hulst. 2 1965, 1966 Neophasia menapia (Feld.) 1 1965 Syngrapha sp. 1 1965 Lithophane lepida (Lintner) 2 1966, 1968 Pristiphora erichsonii (Hartwig) 3 1966 Zeiraphera sp. 3 1966, 1969 Xylotype sp. 1 1966 Eupisilia sp. ] 1966 Dendroctonus obesus (Man.) 1 1968 Zeiraphera destitutana (Walker) 1 1968 Halisidota argentata Pack 1 1968 Orgyia pseudotsugata Midd. I 1969 Leucobrephos brephoides (W\k.) 1 1969 Pikonema dimmockii (Cress.) 2 1968 BACTERIA Bacillus thuringiensis var.galleriae Acronicta grisea (Wlk.) 1 1965 Neophasia menapia (Feld.) 1 1965 Vanessa cardui L. 1 1966 Malacosoma pluviale Dyar 1 1966, 1967 Pristiphora erichsonii (Hartig) it 1966 Neodiprion sp. 1 1966 Bacillus thuringiensis var. thuringiensis Pristiphora erichsonii (Hartig) ] 1965, 1966 Bacillus cereus Eupithecia annulata (Hst.) 2 1965 Lambdina fiscellaria lugubrosa Hulst. 1 1965 Orthosia hibisci Gn. 1 1965 Melanolophia imitata (W1k.) ] 1965 Bacillus brevis Melanolophia imitata (W\k.) ] 1965 Bacillus thuringiensis var. canadensis Lambdina fiscellaria lugubrosa (Hlst.) 1 1966 Neophasia sp. 1 1966 NEMATODES Unidentified Dectroctonus engelmanni Hopk. ] 1950 Trypodendron linneatum (Oliv.) ] 1962 *Indicates pathogenic fungi RESULTS AND DISCUSSION Entomophthora affected 14 species and were found Fungal Pathogens most frequently in two lepidopterous species, viz. Entomophthora and Beauveria were the most Malanolophia imitata (Wlk.), and Lambdina frequently occurring, and the most widely _ fiscellaria lugubrosa (Hlst.). Entomophthora spp. distributed, fungal microorganisms recorded have been reported in numerous other forest insects among forest insects of British Columbia (Table 1). species in all provinces of Canada (MacLeod 1956; 34 TABLE 2. Common forest insects of British Colubmia and microorganisms found in them. Host Melanolophia imitata Malacosoma disstria Malacosma pluviale Ectropis crepuscularia Caripeta divisata Lambdina fiscellaria lugubrosa Lambdina fiscellaria somniaria Acleris variana Neodiprion tsugae Choristoneura fumiferana Hyphantria cunea Stilpnotia salicis Orgyia pseudotsugata Adelges piceae Pristiphora erichsonii Nepytia phantasmaria Nyctobia limitaria nigroangulata Halisidota argentala Fungus Entomophthora sp. Penicillium sp. Verticillium sp. Cordyceps sp. Harmodendrum sp. Trichosporon sp. Entomophthora sp. Beauveria sp. Entomophthora sp. Beauveria bassiana Penicillium sp. Fusarium sp. Alternaria sp. Spicaria sp. (Noumerea) Aspergillus sp. Entomophthora sp. Entomophthora sp. Entomophthora sp. Beauveria sp. Beauveria sp. Penicillium sp. Entomophthora sp. Spicaria sp. Entomophthora sp. Beauveria sp. Penicillium sp. Fusarium sp. Entomophthora sp. Beauveria globulifera Beauveria globulifera Beauveria sp. Beauveria sp. Cephalosporium sp. Penicillium sp. Hirsutella sp. Virus Bacteria NPV Bacillus cereus Bacillus brevis NPV — NPV Bracillus thuringiensis var. galleriae GV NPV = NPV = NPV Bacillus cereus GV NPV GV NPV a NPV — NPV == — Bacillus thuringiensis var. galleriae NPV — NPV _ Protozoa Microsporidia Microsporidia Microsporidia Microsporidia Microsporidia Microsporidia Microsporidia Microsporidia Microsporidia Microsporidia J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DEc. 31, 1983 Nematode J. ENTOMOL. Soc. Brit. CoLumsia 80 (1983), DEc. 31, 1983 35 TABLE 2. (cont’d) Orgyia antiqua badia — Neophasia annulata Eupithecia annulata Choristoneura conflictana — Dendroctonus engelmanni — Trypodendron lineatum _ — Indicates microorganisms not found. MacLeod and Muller-Kogler 1973; Smirnoff and Juneau 1973; Burke 1980) and have a world-wide distribution. Beauveria spp. were isolated from 29 insect species in widespread localities of the province but, generally, the frequency of occurrence was low. Smirnoff and Juneau (1973) reported that 28 insect species were infected by this pathogen in Quebec. B. globilifera isolated from three species, is often treated as a strain of B. bassiana (MacLeod 1954). Cephalosporium sp. were isolated from 6 insect species but the frequency of occurrence was low and geographical distribution was limited throughout the survey period. This fungus is considered by some taxonomists to be only a varietal form of Ver- ticillium sp. (Samson 1981) and has been isolated in Quebec from Toumeyella numismaticum CP. AND M. (Smirnoff and Juneau 1973). Nine other distinct genera of fungi, viz. Penicillium, Fusarium, Alter- naria, Spicaria, Hirsutella, Cordyceps, Aspergillus, Harmodendrum and Trichosporon were isolated from various pest species but with low frequency and restricted distribution. Viruses Nuclear polyhedrosis viruses were isolated from 48 host species of insects, occurring most frequently and with the widest geographical distribution among L. f. lugubrosa, M. imitata, Malacosoma disstria Hbn., L. f. somniaria (Hlst.), Malacosoma pluviale (Dyar), Ectropis crepuscularia Schiff., Stilpnotia salicis L., Orgyia pseudotsugata (McD.), Acleris variana (Fern.) and Neodiprion sp. Electron microscopy of all the Lepidoptera inclusion bodies indicated the presence of multicapsid type of virus (Morris and Olsen 1970). Studies on _ the histopathology, infectivity and epizootiology of some of these viruses have been reported elsewhere (Morris 1962a, 1962b; 1963a, 1963b; 1967). Granulosis viruses were isolated from 11 lepidopterous species but their frequency and distribution were generally low. Nuclear polyhedrosis and granulosis viruses have been isolated from 31 forest insect species in Quebec (Smirnoff and Juneau 1973). Microsporidia Microsporidia were identified in 26 insect species but their incidence and geographic distribution among individual insect species were generally low. The exceptions included Microsporidia recorded in Choristoneura fumiferana, Acleris variana, NPV as = = NPV Bacillus Microsporidia _ thuringiensis var. galleriae NPV Bacillus cereus _ = — = Microsporidia — a ae a Nematode — _ — Nematode Malacosoma_ pluviale and WNyctobia_limitaria nigroangulata. Smirnoff and Juneau (1973) reported that microsporidia were found in 48 species of forest insects in Quebec, including C. fumiferana, C. conflictana, M. disstria and Pristiphora erichsonii. Wilson and Burke (1971) and Wilson (1975) have described the microsporidia from C. fumiferana and C. conflictana. Thomson’s (1960) list of 131 valid species of microsporidia from a vast array of insect species indicates the wide oc- currence of these pathogenic microorganisms. Bacteria Bacillus spp. were isolated from 56 insect species but only 12 isolates were fully identified. These isolates included B. thuringiensis var. galleriae from 6 insect species, B. thuringiensis var. thuringiensis from 1, B. cereus from 4, B. brevis from 1 and B. thuringiensis var. canadensis from 2. The bacterial variety, canadensis, isolated from L. f lugubrosa, the western hemlock looper, and from a Neophasia sp. from Vernon, B.C., is internationally recogniz- ed as a type variety because of its stable crystal- forming characteristic. This variety has also been isolated from Diaropsis sp. and Anisacta sp. in Chad and from Melolontha sp. in Madagascar (de Barjac and Bonnefoi 1972). Smirnoff and Juneau (1973) reported B. cereus from 21 species, B. thur- ingiensis var. thuringiensis from 1 and Bacillus sp. from 14 forest insect species in Quebec. Little is known about the epizootiology of bacterial pathogens of forest insects and the impact of these microorganisms on the _ population dynamics of pest species is relatively obscure. As a group, they probably have little impact compared with that of the viruses, fungi and microsporidia because reported natural epizootics are rare. Nematodes Nematodes were isolated from 2 coleopterous species from the Bolean and Cowichan Lake areas. The impact of nematode infections on forest insect populations is unclear but recent work in agriculture seems to justify continued study of these pathogens for use in integrated control programs. (Finney 1981). Complex of Microorganisms Isolated from Common Forest Insects The list of common forest insect pests of B.C., with their corresponding microbial isolates (Table 2), shows that some pest species are subject to con- siderably greater pressure from natural 36 J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DEc. 31, 1983 microorganisms than others. The green-striped forest looper, M. imitata for example, occurs in western Alberta and throughout British Columbia as a periodic defoliator of western hemlock, Tsuga heterophylla (Raf.) Sarg. and Douglas fir, Pseudt- suga menziesii (Mirb.) Franco. It is attacked by 3 genera of fungi viz. Entomophthora sp.,° Ver- ticillium sp. and Cordyceps sp., a _ nuclear polyhedrosis virus, a microsporidian parasite and 2 species of pathogenic bacteria. The tent cater- pillars, M. disstria and M. pluviale are also attacked by 3 pathogenic fungi, viz. Entomophthora sp., B. dian and a bacterium. Other important pest species which appear to be highly subject to natural diseases include the western hemlock looper, L. f. lugubrosa, the black-headed budworn,, A. variana, the western spruce budworm, C. fumiferana, the fall webworm, Hyphantria cunea, the douglas fir tussock moth, O. pseudotsugata and the pine but- terfly, N. menapia. It is likely that microorganisms play a role in the dynamics of some important economic forest pests of British Columbia and research into their manipulation and their use in pest management strategies seems justifiable. bassiana and Spicaria sp., 2 viruses, a microspori- REFERENCES de Barjac, H. and Bonnefoi, A. 1972. Presence of H antigenic subfactors in Serotype V of Bacillus thur- ingiensis with the description of a new type: B. thuringiensis var. canadensis. J. Invertebr. Pathol. 20: 212-213. Burke, J. M. 1980. A survey of microorganisms infecting a spruce budworm population. Can. For. Serv. Rept. PFM-X-37. 9 pp. Finney, J. R. 1981. Potential of nematodes for pest control. In “Microbial Control of Pest and Plant Disease” H. D. Burges (Ed.). Academic Press, N.Y. pp. 603-620. MacLeod, D. M. 1954. Investigations on the genus Beauveria Vuill. and Tritirachium Limber. Can. J. Bot. 32: 818-890. MacLeod, D M. 1956. Notes on the Genus Empusa Cohn. Can. J. Bot. 34: 16-26. MacLeod, D. M. and Muller-Kogler, E. 1973. Entomogenous fungi: Entomophthora species with pear- shaped to almost spherical conidia (Entomophthorales:Entomophthoracease). Mycologia 65: 823-893. Morris, O. N. 1962a. Studies on the causative agent and histopathology of a virus disease of the western oak looper. J. Insect Pathol. 4: 446-453. Morris, O. N. 1962b. Quantitative infectivity studies on the nuclear polyhedrosis virus of the western oak looper, Lambdina fiscellaria somniaiia (Hlst.). J. Insect Pathol. 4: 207-215. Morris, O. N. 1963a. The natural and artificial control of the Douglas-fir tussock moth, Orgyia pseudot- sugata McDunnough, by a nuclear polyhedrosis virus. J. Insect. Pathol. 4: 401-414. Morris, O. N. 1963b. A nuclear polyhedrosis of Orgyia pseudotsugata: causative-agent and histopathology. Can. J. Microbiol. 9: 899-900. Morris, O. N. 1967. A virus disease of Ectropis crepuscularia Schiff. (Lepidoptera: Geometridae). Can. J. Microbiol. 13: 855-858. Morris, O. N. and Olsen, P. 1970. Insect disease survey in British Columbia 1964-1969. Can. For. Serv. Rept. BC-X-47. 15 pp. Samson, R. A. 1981. Identification: Entomopathogenic Deuteromycetes. In “Microbial Control of Pests and Diseases” H. D. Burges (Ed.). Academic Press, N.Y. pp. 93-106. Smirnoff, W. A. and A. Junean. 1973. Quinze annees de recherches sur les microorganismes des insectes forestieres de la Province de Quebec (1957-1972). Ann. Soc. Ent. Quebec 18: 147-181. Thomson, H. M. 1960. A list and brief description of the Microsporidia infecting insects. J. Insect Pathol. 2: 346-385. Wilson, G. G. 1975. Occurrence of Thelohania sp. and Pleistophora sp. (Microsporidia: Nosematidae) in Choristoneura fumiferana (Lepidoptera: Tortricidae). Can. J. Zool. 53: 1799-1802. Wilson, G. G. and J. M. Burke. 1971. Nosema thomsoni n. sp., a microsporidian from Choristoneura con- flictana (Lepidoptera: Tortricidae). Can. J. Zool. 49: 786-788. J. ENTOMOL. Soc. Brit. COLUMBIA 80 (1983), DEc. 31, 1983 on A TEST OF THE EFFICACY OF IMMUNIZING CATTLE AGAINST ROCKY MOUNTAIN WOOD TICKS P. R. WILKINSON! AND J. R. ALLEN? ABSTRACT Nine yearling steers were inoculated with an extract of Dermacentor variabilis (Say) suspended in aluminum hydroxide adjuvant in an attempt to increase their resistance to the feeding of Dermacentor andersoni Stiles. However, when these cattle were infested with D. andersoni ticks, there were no significant differences in the proportions of ticks feeding, or mean weights of fed ticks, in comparison with nine cattle treated with adjuvant only, or with two untreated cattle. Five of the cattle in each of the treated groups received additional ticks to test for susceptibility to tick paralysis. Three of the cattle treated with tick extract became paralysed, as did one of the cattle treated with adjuvant only. Serological responses to the im- munizing antigen, assayed by indirect haemagglutination, were relatively weak. Some possible reasons for the ineffectiveness of the immunization, in contrast to earlier positive studies with guinea pigs and a few cattle, are discussed. The methods described should contribute to testing the practical efficacy of promising antigens as they are produced. INTRODUCTION Serious outbreaks of tick (Dermacentor ander- soni Stiles) paralysis of livestock occur periodically in British Columbia (Gregson 1966). The recom- mended preventive treatment consists of spraying acaricides on the backs of cattle before they enter the tick-infested pastures in early April (Costello and Khan 1980, Wilkinson 1981). Although these chemical treatments have provided very useful pro- tection they have several disadvantages, including periodic changes in the regulations on registration and permissible residues, and the possibility of the ticks becoming resistant to pesticides. Sometimes the protection provided (about 3 weeks for a 0.25 % lindane spray) is insufficient, necessitating gather- ing the cattle from extensive rangeland and respraying. Allen and Humphreys (1979) reported signifi- cant reductions in the weights of D. andersoni adults fed on ears of calves which had previously been immunized with extracts of partially fed female D. andersoni ticks, in comparison with con- trol calves. They speculated that control of tick in- festations, following artificial immunizations, might be feasible. Several authors have reported encouraging results in increasing the resistance of laboratory animals to ticks, by immunization with various ex- tracts and organs of ticks (Wikel and Allen 1982). In field testing of acaricides, one of us (P.W.) noted that untreated cattle developed skin reactions with serous exudate at the sites of tick attachment, after three weeks exposure to ticks. In the field, these skin reactions appeared to inhibit the feeding and attachment of the ticks (cf. Wikel and Osburn "Research Station, Research Branch, Lethbridge, Alberta T1J 4B1 *Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan S7N 0WO Agriculture Canada, 1982). It was reasoned that an antigen treatment prior to exposure to ticks might have the effect of producing these skin reactions within a few days of tick attachment to the cattle. A limited quantity of freeze-dried antigen, prepared from Dermacentor variabilis (Say) ticks in 1978, was available for use in a pilot experiment. Though this antigen came from a different species of tick, it was used in the knowledge that cross- reactions in immunologically mediated _ tick- resistance have been demonstrated between these two species (Trager 1939, McTier et al. 1981). Because of a shortage of antigen and logistical pro- blems with a field trial, the study described here was carried out with penned cattle, as a preliminary test of the potential of controlling tick paralysis by manipulating the immunological systems of the cattle. The conclusions are based mainly on the com- parison of weights of ticks fed on treated and con- trol steers. A larger dose of ticks was given to some steers to see if differences in susceptibility to paralysis could be observed. Although the im- munization failed as a protection against tick feeding and paralysis, the prospects for eventual success are promising, and this paper records test procedures that may be useful to other workers. METHODS On March 20, 1982, nine Hereford yearling steers (group T) were each injected with tick- derived antigen and aluminum hydroxide adjuvant, and a similar group of steers (group A) was injected with sterile saline and adjuvant only. Two other steers were left untreated (group U). On March 25, group T had a mean weight of 252 kg (range 240-282 kg), group A had a mean weight of 258 kg (range 240-292 kg), and the two untreated cattle weighed 254 and 276 kg. On April 3, repeat ‘booster’ injections were administered to all animals in groups T and A. 38 J. ENTOMOL. Soc. Brit. CoLumsia 80 (1983), DEc. 31, 1983 The antigen given to animals in group T was a saline extract of internal organs from D. variabilis females that had fed on Hereford cattle for 5 days. The extract was prepared in 1978 and lyophilized. Freeze-dried material was reconstituted in sterile saline, and equal volumes of this solution (which contained 20 mg protein/ml, by Lowry assay) and Alhydrogel (Connaught) were allowed to react for 24 hours at room temperature before a total dose of 20 mg protein was injected subcutaneously at four sites on each animal in group T. Group A animals received similar injections of saline and Alhydrogel. Serum samples were taken from each animal in groups T and A prior to the first injection, at the time of the booster injection, and at the start of the tick infestation. These sera were titrated by indirect haemagglutination, with the same antigen attached to red cells. On April 19 and 20, after hair was closely clip- ped from the area of contact, a sleeve cut from a child-size sock was fixed to the withers (Wilkinson 1972) of each of the 20 animals with contact ce- ment. The hair within the sock was left about 1.5 cm in length. Two additional sleeves were fitted to five animals in each of groups T and A to allow for increased tick infestation and to test for susceptibili- ty to paralysis. The sleeves are referred to as sleeve 1, sleeve 2, and sleeve 3, on each animal concerned. Ticks On April 21, 30 male and 30 female ticks from a laboratory culture were placed in each sleeve 1. Thirty female ticks collected from vegetation during March and April and stored at 5°C 95% RH were placed in each sleeve 2. On four animals, in each of groups T and A, sleeve 2 ticks were collected within 64 km of Kamloops, B.C., and on the remaining animal in each of these groups ticks were an Alberta strain bred on rabbits kept outdoors in a ‘roden- tarium’ (Wilkinson 1968). In each sleeve 3 the in- festation was 60 females from the same culture used in sleeve 1. This culture was reared from larvae and nymphs fed on laboratory rabbits indoors. The lar- vae originated from ticks collected near Kamloops in 1981. The engorged nymphs were kept in unlit incubators at 25°C 75% RH until ecdysis was com- plete on January 12 and the resulting adults at 5°C 95% RH until April 20. On April 20, they were ex- posed to fluorescent room lighting from 0845 to 1645 hrs, while still in glass tubes in a glass humidifier, with similar treatment the next day un- til placement on the cattle at 1330 hrs. Room temperatures commenced at 8°C, rose to 15°C, then dropped to 7°C at night, and rose again to 15°C. These temperatures and light changes were intended to assist in breaking the diapause (Wilkin- son 1973). On April 28 the sleeves were opened, dead ticks were removed and the progress of feeding was checked qualitatively. On April 30 and May 1 ticks were removed from animals that were paralysed to the stage of sternal recumbency. All remaining ticks from all animals were removed on May 3. The ticks from each sleeve were stored at 5°C 95% RH in separate tubes, then counted and weighed. To ob- tain mean weights of fed female ticks, male ticks and females with no appreciable enlargement of the opisthosoma (red colored ticks) were discarded and the number of fed females with tan and grey col- ored opisthosomata was divided into their total weight, for each sleeve. RESULTS Examination on April 28 The total number of dead ticks in sleeves 1 was similar for groups T, A and U, allowing for numbers of sleeves. There were 22 male and 43 females from group T, 17 males and 38 females from group A, and 7 males and 8 females from group U. Since the sleeves were left in place, some dead ticks may have been missed. Qualitatively, TABLE 1. Weights of fed female ticks removed on day of paralysis, in relation to weights of cattle on May 6, 1982. Treatment code: T = cattle treated with tick antigen, A = cattle that received adjuvant on- ly. The ticks were placed on the cattle on 21 April 1982. Animal Weight Date No. (kg) Treatment paralysed 316 267 iT Apr 30 319 285 uk Apr 30 318 276 We May 1 330 256 A May 3 Total weight (g) female ticks in sleeve Parasite il 2 3 ratiot 4.19 5139 3.67 Sosa 2.05 3.91 1.40 25 soir 4.83 5.88 Sy ia 45.032 2.24 8.34 3.42 54). 1 5 oe ‘ . ‘ : Weight of all fed ticks in mg: weight of steer in kg. J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DEc. 31, 1983 39 TABLE 2. Mean weights of fed female ticks (FFT) in sleeves 1, 2 and 3 on paralyzed animals on day of ster- nal recumbency and sleeves 2 and 3 on unparalysed animals on May 3, 1982. See text for weights of ticks in sleeve 1 on May 3, on unparalyzed animals. Sleeve Treatment No. P=paralysed Mean wt. class of cattlet replicates NP=not paralysed FFT (mg) 1 T 3 P 167 1 A 1 P 448 2 T 3 P 190 2 A 1 P 298 3 T 3 P 81 3 A 1 P 155 2 ay 2 NP 342 2 A 4 NP 281 3 Tt 2 NP 215 3 A 4 NP 137 7 = treated with tick antigen, A = treated with adjuvant only. degree of engorgement of live ticks appeared to be similar among groups. Mortality of ticks in sleeves 2 was low, while in sleeves 3 the number of dead females per sleeve was higher than in sleeves 1, i.e., a total of 41 in 5 sleeves in group T and 48 in 4 sleeves counted in group A. Occurrence of paralysis Table 1 shows the treatment groups of paralysed animals. On April 30, animal 319 was in sternal recumbency at 0800 hrs. All ticks were removed, commencing at 0830 hrs. The animal was still unable to rise at 1130 hrs, but was unsteadily on its feet at 1415 hours. At 1415 hours, animal 316 was unsteady; it was sternally recumbent at 1945 hrs when all ticks were removed from it. On May 1, animals 319 and 316 had recovered, but 318 was sternally recumbent at 0815 and the ticks were removed. No animals were paralysed on May 2. On May 3 at 0815, animal 330 was in sternal recumbency, but regained its feet and was able to walk to the examination chute in the afternoon. However, at 1600 hrs it collapsed while entering the chute and the ticks were removed while it was in sternal recumbency. This animal was normal the next day. The weights of the fed ticks in relation to animal weight are shown in Table 1, for com- parison with other records of paralysis (Wilkinson 1982). Paralysis did not occur in the two animals carrying Alberta ‘rodentarium’ ticks in sleeve 2. Weights and numbers of fed ticks removed on May 3, 1982 A comparison of the effects of immunization on degree of engorgement of the cultured ticks can be based on the mean weights of fed ticks in sleeves 1 on May 3. Ticks from animals paralysed before that date are not comparable, since the ticks were removed after a shorter feeding period. Weights of ticks in sleeves 2 and 3 are less significant, since only two of five animals with three sleeves each remain- ed unparalysed in group T until May 3. Mean weight of fed female ticks in the tan and grey stages, removed from sleeves ] in group A on May 3, was 494 + 41.72 mg (P = 0.05) (includes animal 330). In group T the mean weight of fed female ticks from the six ‘not paralysed’ animals was 477 + 54.81 mg. In group U the mean was 455 mg, N = 2. The differences between the means were not significant. Some other mean values, for which significance of between-group differences was not tested, because of the small number of replicates, are shown in Table 2. On the paralysed animals, mean weights of ticks from the T group animals were lower than those from the A group animal 330, because the ticks were removed from the latter at a later date. On the ‘not paralysed’ animals mean weights of ticks in sleeves 2 and 3 were slightly greater in group T than in group A. One sleeve 2 on an unparalysed animal in group T contained a male tick, resulting in apparent fer- tilization and increased weight of 7 out of 31 females. These seven females, and eight females from a sleeve 1 of an unparalysed T group animal, were transferred to 25°C. and high humidity where they produced normal egg masses and numbers of larvae, except that percentage hatch was below nor- mal for one egg mass. Thus, the antigen treatment did not affect the fertility of the engorged females as reported by Brossard and Girardin (1979) and C.S.1.R.O. (1983). There were also two sleeves 2 in group A containing 31 females instead of the correct number, 30. These errors had a negligible effect on the conclusions from the experiment. The numbers of ticks per sleeve that fed ap- preciably in sleeves 1 were group T 19.56, group A 40 J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DEc. 31, 1983 15.33, and group U 12.5. For sleeves 2, the mean numbers of fed females in groups T and A were 28.0 and 29.4 and for sleeves 3, 28.0 and 20.8, respec- tively. The differences in the mean numbers of fed ticks in sleeves 1 in groups T and A were not signifi- cant. There were insufficient replicates of the other sleeves to warrant testing of significance of the small differences of means. Results from serological work Titres of 1:20 were recorded occasionally from animals in group A (Table 3). Such titres could be considered as false positives, or at best insignificant. Titres of 1:40 were obtained from two animals in group T at the time of the booster injection, and titres to 1:640 were found in immunized animals at the time of tick infestation. DISCUSSION The inoculation did not produce any significant difference in mean weight of fed ticks compared with the adjuvant-only treatment. The mean weight per fed tick was used to eliminate variability in the number of ticks that fed in each sleeve. The numbers of ticks that fed in sleeves 1, 2 and 3 were not significantly different between groups T and A. Hence, the treatment did not significantly affect the attachment and feeding of the ticks. Further work is necessary to determine whether the antigen produced increased susceptibility to paralysis, since the number of cases was too low for statistical inference. Serological results indicated relatively poor responses to the D. variabilis antigen in immunized animals. Previous work (Allen, unpublished) show- ed that titres of at least 1:1280 were associated with effects on tick feeding. The low titres could have been due to several causes, including low doses of antigen and deterioration of antigen in storage. The lack of effects on tick feeding, in contrast to the results of Allen & Humphreys (1979), could have been due to differences in total antigen dose (which was less than ‘4 of that used in their experiment), the dosage regimen or insufficient cross-reactivity bet- ween D. variabilis and D. andersoni antigens. Further purification of D. andersoni antigens, which is now being done, and further immuniza- tion trials with higher doses of antigens will be re- quired before an immunological approach to the control of tick paralysis can be recommended. The laboratory-bred ticks displayed a lower percentage of successful attachment than did the wild ticks, and a higher preattachment mortality. Mean weights of fed ticks were generally less in sleeves 3 than in sleeves 2 on May 3. These effects were probably due to difficulty of terminating diapause in laboratory cultures (Wilkinson, 1973). TABLE 3. Serological results: [HA titres from animals in groups T and A. Animal Pre- no. Group treatment 3. uy 0 312 7 0 o13 T 0 314 Ay 0 316 Ay 0 317 WW 0 318 Ak 0 319 T 0 320 Ay 0 321 A 0 572 A 0 323 A 0 324 A 0 325 A 0 326 A 20 327 A 0 328 A 0 THA titres At time of At start of booster infestation 0 1:160 1:20 1:160 0 1:640 13:20 £3320 0 1:160 1:40 1-320 0 P3320 1:40 1:40* 1320 1:40 0 0 1:20 1:20 0 0 0 0 0 0 L320 0 0 0 0 1320 *Animal 319 suffered from pneumonia one week before the last serum sample was taken. J. ENTOMOL. Soc. Brit. COLUMBIA 80 (1983), DEc. 31, 1983 4] Despite this, the test was useful as a demonstration potential vaccines, using penned cattle and both of methods available for testing the efficacy of — wild and cultured ticks. REFERENCES Allen, J. R. and S. J. Humphreys. 1979. Immunization of guinea pigs and cattle against ticks. Nature 280: 491-493. Brossard, M. and P. Girardin. 1979. Passive transfer of resistance in rabbits infested with adult Ixodes ricinus L.: Humoral factors influencing feeding and egg laying. Experientia 35: 1395-1397. Costello, R. A. and M. A. Khan. 1980. Control of insects and ticks on livestock. British Columbia Ministry of Agriculture, Victoria. C.S.I.R.O. 1983. Ann. Rept. Div. An. Hlth. 1982. p. 35. Commonwealth Scientific and Industrial Research Organization, Melbourne, Australia. Gregson, J. D. 1966. Records of tick paralysis in British Columbia. J. Entomol. Soc. B.C. 63: 13-18. McTier, T. L., J. E. George, and S. N. Bennett. 1981. Resistance and cross-resistance of guinea pigs to Der- macentor andersoni Stiles, D. variabilis (Say), Amblyomma americanum (Linnaeus), and Ixodes scapularis Say. J. Parasitol. 67: 813-822. Trager, W. 1939. Acquired immunity to ticks. J. Parasitol. 25: 57-81. Wikel, S. K. and J. R. Allen. 1982. Immunological basis of host-resistance to ticks. In: Obenchain, F. D. and Galun, R. (Eds), Physiology of ticks. Pergamon Press, Oxford, p. 169-196. Wikel, S. K. and R. L. Osburn. 1982. Immune responsiveness of the bovine host to repeated low-level in- festations with Dermacentor andersoni. Ann. Trop. Med. Parasit. 76: 405-414. Wilkinson, P. R. 1968. Phenology, behavior, and host relations of Dermacentor andersoni Stiles in outdoor ‘rodentaria’ and in nature. Can. J. Zool. 46: 677-689. Wilkinson, P. R. 1972. Sites of attachment of ‘Prairie’ and ‘Montane’ Dermacentor andersoni (Acarina: Ix- odidae) on cattle. J. Med. Ent. 9: 133-137. Wilkinson, P. R. 1973. Termination of diapause in laboratory-reared Dermacentor andersoni adults. Proc. 3rd Int. Congr. Acarol. (Prague 1971) pp. 803-806. Wilkinson, P. R. 1981. Field test of phosmet and chlorpyrifos formulations for prevention of tick paralysis of cattle. Pesticide Research Report 1980. E.C.P.U.A., Agriculture Canada, Ottawa. Wilkinson, P. R. 1982. Paralysis by Rocky Mountain Wood Ticks (Acari: Ixodidae) of cattle breeds other than Hereford. J. Med. Ent. 19: 215-216. 42 J. ENTOMOL. Soc. Brit. COLUMBIA 80 (1983), DEc. 31, 1983 ON THE RELATIONSHIP BETWEEN THE EUROPEAN RED MITE AND APPLE LEAF CHLOROPHYLL DANIEL L. JOHNSON! Institute of Animal Resource Ecology University of British Columbia, V6T 1W5 ABSTRACT Chlorophyll content of Delicious and McIntosh apple leaves is shown to be un- correlated with numbers of the European red mite (ERM). Hypotheses regarding movement by the ERM are examined. It is concluded that there is no evidence that the ERM seeks out the least damaged leaves, nor can leaf damage be attributed to the mites present on the leaves. Movement unrelated to leaf quality explains the lack of correlation. INTRODUCTION Spider mites have been serious orchard pests in British Columbia since the 1940s (Marshall, 1951, 1952). The most troublesome tetranychid orchard mite in most regions is the European red mite (Panonychus ulmi (Koch) ), so-called since it is thought to have been introduced into North America from Europe in the early years of this cen- tury’. The European red mite (ERM) feeds on the leaves of apple, pear and a host of other fruit and ornamental trees. The attacks reduce fruit produc- tion and quality during the year of attack and the number of flower buds the following year (Madsen and Arrand, 1975; van de Vrie et al., 1972). The ERM has 6 to 8 generations per year, depending on temperature, photoperiod and food quality. In May, eggs hatch and give rise to the first generation. All stages, larvae, protonymphs, deutonymphs and adults, can be found throughout the summer. The production of winter eggs occurs in August and September. Feeding Damage Most spider mites are phyllophagous, that is, they feed on leaf tissue and not on other plant parts. European red mites feed by inserting cheliceral stylets into mesophyll cells and sucking out the cell contents. The mouth-parts penetrate to a depth of about 50-100 u (Avery and Briggs, 1968), damag- ing the palisade mesophyll and, to a lesser extent, the spongy mesophyll. Parenchyma is not damaged. Fluid loss results in cell death, and cells adjacent to damaged cells exhibit aberrant organelle structure (Tanigoshi and Browne, 1981) and reduce their ac- tivity, or die. Leaf surfaces are characteristically speckled with dead and weakened cells at low to moderate levels of damage, and become chlorotic (light-coloured due to chlorophyll loss) if the damage is extreme. The tell-tale bronzing from the loss of fluid and pigments is recognizable from a distance as an indicator of high mite population density. 'Present address: Research Station, Lethbridge, Alberta T1J 4B1. There is some evidence that European red mites move from damaged leaves. Asquith et al. (1980) report the effects of leaf damage caused by rust mites on the ERM. Although developmental time and survival were unaffected by the degree of damage, 60% of young adult females moved from damaged to undamaged leaves. Other laboratory and field observations suggest that young adult females have a tendency to walk away even from fresh, undamaged leaves (Johnson, 1983). Within-tree dispersal, leaf condition and the reproductive success of mites are interrelated. Mite damage affects leaf condition, and leaf quality may influence mite behavior. Mites may or may not be highly mobile and sensitive to food-quality dif- ferences within a tree. They may disperse in response to food, randomly, or in response to the behavior they adopt during dispersive phases. The empirical relationship between mite numbers and chlorophyll content, an index of leaf damage, can provide indirect evidence that allows inference on the hypothetical relationships between dispersal and feeding. Chlorophyll concentration is also an indicator of leaf quality, since healthy, green leaves are generally believed to be the most nutritious (e.g., females on damaged leaves suffer a 90% decrease in fecundity, Asquith et al., 1980). Three hypotheses and corresponding predictions of the nature of the empirical relationship between mite numbers and chlorophyll content are detailed below. I: European red mites are highly mobile and choose the best leaves, i.e., the leaves which are relatively undamaged and highly palatable. Prediction: a positive correlation between leaf chlorophyll content and the number of mites on the leaves, since mites search out the best feeding sites and remain until food quality degrades. II: The mites are relatively incapable of movement between leaves and of food selection. They re- main on the leaf even after it has sustained 2In Europe it is called the fruit-tree red spider mite. J. ENTOMOL. Soc. BriT. COLUMBIA 80 (1983), DEC. 31, 1983 43 heavy feeding damage. Prediction: a negative correlation between chlorophyll content and mite numbers, since the degree of leaf damage reflects its present mite population. III: Mites are capable of movement between leaves, but do so in a way which is not determined by food condition. They may move if the food quality declines, or they may move even if it re- mains high. Prediction: no correlation between chlorophyll and mites. Compound action of these hypothesized pro- cesses would produce compound results. If, for ex- ample, mites sought out leaves with high chlorophyll content and remained to feed, but at high densities they reduced chlorophyll content significantly, we would expect to find a parabolic relationship between chlorophyll content and number of mites per leaf. MATERIALS AND METHODS The relationship between the ERM and apple leaf chlorophyll was assessed in the Entomology Or- chard at the Agriculture Canada Research Station, Summerland, British Columbia. The sampling design was part of a predator-removal experiment described by Johnson (1983). This larger experiment provided trees with a wide range of densities of the ERM. On each of three dates (June 10 & 11, June 24 & 25 and August 5 & 6) 10 leaves were collected from each of 32 Delicious and 32 McIntosh apple trees ar- ranged in an 8 x 8 Latin square. Of the 10 leaves ina sample, 5 came from the north and 5 from the south branch of each tree. Leaves were collected random- ly, with the proviso that no very young or very old leaves were taken. Each leaf was individually plac- ed into a 15 cm diameter plastic petri dish. These were transferred to 2-4°C storage within 15 minutes of collection. Collections were made row by row, with the order randomized on each sampling date. This pattern ensured that any variability in the results due to time or order of collection could be ac- counted for by row effect. Sampling was restricted to the period between 9 a.m. and 8 p.m. In the field laboratory, the leaves were examined in- dividually with a binocular dissecting microscope. The mites were counted via direct observation and categorized according to species, sex and instar. Collection of the 640 leaves per sampling date was usually accomplished in two days, with examina- tion and counting requiring up to another two days. At each of the three dates, an additional sample of 100 leaves was randomly selected and used for determination of moisture content. These leaves were weighed fresh, examined for mites and dried to constant weight at 70°C. After the mites were counted, each of the 64 10-leaf samples per date was immediately bagged and frozen. The samples were kept frozen from 2 to 5 months. The mite counts on the 10 leaves per tree were pooled; thus one 10-leaf sample represents one observation on mite density and chlorophyll con- tent. From each leaf in a sample a 1.6 cm diameter disk was cut with a brass cork-borer and used for quantitative determination of chlorophyll a and b by the spectrophotometric method of Bruinsma (1963). A second set of similar disks was cut from TABLE 1. Mean numbers of the European red mite per leaf. The means for each date are calculated from the counts on 320 leaves, with standard errors ( ). adults total eggs larvae nymphs z of active ERM a) Delicious mune ORE 2257 (3-4) 8.80.38) 5051208) Som 207) 208 02) 4.9 048) Junew2 4825" 73878. (5.9)' Pol (12) 320 AG) 8 43) 1.4. (216) 1256 C269) Aug. 5&6 60.7 M350). 8.5: C61), 42e3) (327) 98.2 (744) 453° (235) 64.3 (4.1) b) McIntosh June 10&11 SIO ~OlO)" 384 (13) 2.013 (.0)) 22° (04) 3003 (003) desk. {45} June; Z4N25o: 36401 (3.2), .50 (.08). ~97 (.11)- 3.6 (,22) 7497 07) DO? Viod) a Aug. 5&6 SOC 29): 130) (228) 522 Ae), Ae? Gaze) no -C.26) 246° (127) 44 J. ENTOMOL. Soc. Brit. CoLumsiA 80 (1983), DEc. 31, 1983 TABLE 2. Mean chlorophyll content in mg/g dry weight, of McIntosh and Delicious leaves. Means and standard errors ( ) are based on 32 samples. Date McIntosh Delicious June 10 ‘&% 11 3.05. (0.095) 3.81 (0.078) June 24 & 25 3.22 (0,094) 3.637 (0090) August 5 & 6 2,82 (0.065) 3.37 (05066) the same leaves for dry weight determination. From each sample, the 10 leaf disks were finely chopped in a blender in 50 ml of cold (1-4°C) 80% acetone, 20% distilled water. The slurry was suction-filtered over ice, and washed with 20 ml of cold 80% acetone solution. Determinations of total chlorophyll were made with a spectrophotometer by measuring absorbance at 652 nm against an 80 % acetone standard. This peak absorbance wavelength, given by Bruinsma (1963), was verified by a scan of sample filtrate with a more precise Unican SP.800 spectrophotometer. As a check on total chlorophyll, absorbances at 663 nm and 645 nm were measured for calculation of chlorophyll a and b content respectively. Concentrations of chlorophyll were determined using the equations of Bruinsma (1963). These were converted to mg/g dry weight, based on the second set of leaf disks from each sample, and to mg/cm? leaf area. Determina- tions were made for a total of 192 10-leaf samples, collected on the three sampling dates: June 10 & 11, June 24 & 25, and August 5 & 6. RESULTS All stages of the ERM were about twice as numerous on Delicious as on McIntosh (Table 1). This difference is well-known to growers and en- tomologists (Downing and Moilliet, 1967). Delicious trees often require more acaricide ap- plications than do trees of other apple varieties (B.C.M.A., 1980). The difference can be attributed to some quality of the leaves, and not to indirect ef- fects of phytoseiid predators. Counts of Typhlodromus spp. were about twice as high on Delicious leaves as on McIntosh leaves (Johnson, 1983). Leaf moisture content was unrelated to the number of mites present; the slope is not significant- ly different from zero (p~0.3). On all three dates, 70-78% of fresh weight was lost during drying. Leaves of Delicious had a higher chlorophyll content than those of McIntosh on all three dates (p < .0001). Chlorophyll content (mg/g dry weight) was higher in June than in August in both cultivars (p < .0001) (Table 2). Chlorophyll per unit area (not shown) gave similar results. Although a wide range of mite densities was present in the data, varying from 0 to 2260 per 10-leaf sample, correla- tions between mite counts per 10-leaf sample and chlorophyll determinations (a, b and total) were not significant (p > .05) for either cultivar on any of the three sampling dates (Table 3). When apple cultivar was ignored, a significant but spurius positive correlation (p < .01) resulted, due to the fact that more European red mites were found on Delicious than on McIntosh. DISCUSSION There does not seem to be any evidence for the ERM seeking out the least damaged leaves, at least as indicated by chlorophyll content. Nor can leaf damage be attributed to the mites present on the TABLE 3. Correlation (r) between number of European red mites and chlorophyll content in mg/g dry weight of leaves. Each statistic is based on 32 observations. Date June 10 & 1l June 24 & 25 August 5 & 6 McIntosh Delicious 0.130 0.260 OZ326 -0.239 -0.234 -0.141 J. ENTOMOL. SOc. BRIT. COLUMBIA 80 (1983), DEC. 31, 1983 45 leaves. This lack of correlation supports hypothesis III, not I or II. In effect, mites are not consistently influenced by food quality during their movements between leaves. It is well-known that the presence of large numbers of ERM is associated with apple leaf bron- zing. Orchards with high average densities of mites will show more yellowing than orchards with few mites. However, the results of this study show that chlorophyll content is not related to the associated density of mites at the scale of the leaf. It can be concluded that ERM dispersal among leaves is within-orchard (Johnson, 1983) dispersal rates pro- bably account for this distribution of mite damage. ACKNOWLEDGEMENTS I am indebted to Dr. R. D. McMullen for his permission to work at the Summerland Research Station, and to Simon Fraser University for the use of their facilities. I thank Dr. W. G. Wellington for his comments and critical review. Héléne Contant, Cathy Johnson and Roy Ward provided invaluable technical assistance. The author was supported by an NSERC Scholarship and a Killam Predoctoral relatively rapid and not strongly related to leaf con- holarship during the study. dition. High within-branch, within-tree and Se ae es cy REFERENCES Asquith, D., B. A. Croft, S. C. Hoyt, E. H. Glass and R. E. Rice. 1980. The systems approach and general accomplishments toward better insect control in pome and stone fruits. In: New Technology of Pest Control, C. B. Huffaker (ed.), John Wiley, N.Y., pp. 249-317. Avery, D. J. and J. B. Briggs. 1968. Damage to leaves caused by fruit tree red spider mite, Panonychus ulmi (Koch). J. Hort. Sci. 43: 463-473. British Columbia. Ministry of Agriculture. 1980. Tree fruit production guide for interior districts. 63 p. Bruinsma, J. 1963. The quantitative analysis of chlorophylls a and b in plant extracts. Photochem. Photobiol. 2: 241-249. Downing, R. S. and T. K. Moilliet. 1967. Relative densities of predacious and phytophagous mites on three varieties of apple tree. Can. Ent. 99: 738-741. Johnson, D. L. 1983. Predation, dispersal and weather in an orchard mite system. Ph.D. thesis, University of British Columbia, Vancouver. Madsen, H. F. and J. C. Arrand. 1975. The recognition and life-history of the major orchard insects and mites in British Columbia. British Columbia. Department of Agriculture. Publication. Marshall, J. 1951. Applied entomology in the orchards of British Columbia, 1900-1951. Proc. Ent. Soc. B.C. 48: 25-31. Marshall, J. 1952. A decade of pest control in British Columbia orchards. Proc. Ent. Soc. B.C. 49: 7-11. Tanigoshi, L. K. and R. W. Browne. 1981. Coupling the cytological aspects of spider mite feeding to economic injury levels on apple. Protection Ecol. 3: 29-40. van de Vrie, M., J. A. McMurtry and C. B. Huffaker. 1972. Ecology of tetranychid mites and their natural enemies: a review. III. Biology, ecology, and pest status, and host plant relations of tetranychids. Hilgardia 41: 343-432. 46 J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DeEc. 31, 1983 THE ODONATA OF THE BROOKS PENINSULA, VANCOUVER ISLAND, BRITISH COLUMBIA* ROBERT A. CANNINGS Entomology Division, B.C. Provincial Museum, Victoria, B.C. V8V 1X4 AND SYDNEY G. CANNINGS Department of Zoology, University of B.C., Vancouver, B.C. V6T 2A9 ABSTRACT Collection records of Odonata from the Brooks Peninsula, a little-known region on the northwest coast of Vancouver Island, are presented. Twenty species representing eight genera and five families are listed, along with additional ecological notes. The zoogeography of the Odonata of the British Columbia coast is discussed. INTRODUCTION The Odonata of the outer west coast of British Columbia is poorly known; the few available records for the region are listed in Cannings and Stuart (1977), Cannings (1980), Scudder et al. (1976), Walker (1953, 1958) and Walker and Cor- bet (1975). It is notable that virtually no published records of dragonflies exist for Vancouver Island north of the latitude of Campbell River. In 1981 a multidisciplinary expedition organized by the B.C. Provincial Museum provided an oppor- tunity to study the insects of the Brooks Peninsula, a remote region, inaccessible by road, on the nor- thwestern coast of Vancouver Island. From 31 July to 14 August 1981, a significant collection of dragonflies (244 adults and 242 larvae) was made in this area. This material enables us, for the first time, to compare the fauna of northern Vancouver Island with that of adjacent regions. THE STUDY AREA The Brooks Peninsula is a rugged rectangle of land, 22km long and 10km wide, projecting into the Pacific Ocean from northwestern Vancouver Island (Figure 1). It lies between 50° 05’ and 50° 15’N latitude and 127° 37 and 127° 55’W longitude. The precipitous central ridge reaches an elevation of 1000m, and steep valleys, many containing cirque lakes, run to the south and southeast shores. On the headlands the peaks are rounded and _ lower, reaching 500m, and are scoured by high winds. On the northwest a broad, undulating lowland extends from the central ridge to the shore. Blanket bogs on this lowland provide the best habitats for dragon flies. Small pools and channels are frequent in the ir- regular surface peat deposits in these bogs. An open scrub forest of lodgepole pine (Pinus contorta), yellow cedar (Chamaecyparis nootkatensis) and western red cedar (Thuja plicata) dominates the vegetation. Small shrubs such as salal (Gaultheria *Brooks Peninsula Refugium Expedition 1981 Contribution No. 3, British Columbia Provincial Museum, Victoria, B.C., V8V 1X4; supported by a grant from the Friends of the British Columbia Pro- vincial Museum. shallon), labrador tea (Ledum groenlandicum) and crowberry (Empetrum nigrum) are abundant. Sedges, rushes and grasses as well as diverse her- baceous species cover the ground; especially prevalent are Scirpus caespitosus, Eriophorum polystachion and Rhynchospora alba. Liverworts and mosses, particularly Rhacomitrium lanuginosum and Sphagnum species, form mats and hummocks. The larger lakes are less productive, lacking the extensive organic sediments and aquatic plants prevalent in bog waters. Most have rather steep- sided basins with cobbly shores, usually supporting pockets of Carex. Kalmia Lake is an example of this type, although it is adjacent to bogs, unlike others such as Gaultheria Lake which lies in a narrower, more heavily forested basin. Cassiope Lake is the most productive of the non-bog water bodies. It is a shallow pond perched on a ridge at 520m bordered by a small subalpine meadow. SPECIES LIST LESTIDAE Lestes disjunctus Selys L. disjunctus was only just beginning its flight period in late July on the Brooks Peninsula. At Cassiope Lake on 31 July evaporation of a small pool concentrated the remaining water to a puddle 0.3m x 1.0m x 2cm deep; it contained about 150 full-grown larvae which emerged over the next week. Teneral females were present at Gaultheria Lake on 1 August and recently emerged males flew at Toebiter Bog on 6 August. Copulation and oviposition were observed from 7 August (Brasenia Lake) onwards. Eggs were laid mainly well up on the culms of Juncus oreganus in both dry and emergent situations. As most localities mature males only were observed before 12:00h; copulation and oviposition peaked at about 14:00h. COENAGRIONIDAE Enallagma cyathigerum (Charpentier) E. cyathigerum and Lestes disjunctus, the only Zygoptera collected, are both widely distributed on the Brooks Peninsula. Both were numerous in early J. ENTOMOL. Soc. Brit. COLuMBIA 80 (1983), DEc. 31, 1983 47 A = / ° cO — yi N fl ¢ 2) Q (A Prince my \ Rupert oy ‘, Queen Charlotte Is. ) Brooks Peninsula ° Vancouver Vancouver Is. ae 2a “8 fi) 50°N 0, MOD Danae Pond Gaultheria L. e °* Brasenia L! [fs 0 oO D e ~~ »-Kalmia L. ° 5 ° iG ~Cassiope L. oO > (es ra) 3km Fig. 1. Study Area. A: Pacific coast of British Columbia showing location of Brooks Peninsula. B: Brooks Peninsula showing main collection sites. August, although at least part of the E. cyathigerum population was mature by the end of July; considerable copulation and oviposition took place at Cassiope Lake on 31 July. In southern British Columbia E. cyathigerum emergence usual- ly precedes that of L. disjunctus by about six weeks. Immature adults were observed “hilltopping”; specimens were captured on the ridge to the east of Cassiope Lake (700m) on 31 July. Both heterochromatic and homeochromatic phases were present in the female population, some of the latter showing very extensive black pigmentation. AESHNIDAE Aeshna eremita Scudder A. eremita is the principal dragonfly of the lakes on the Brooks Peninsula in midsummer; oviposition and larval development occurs mainly along the shores of these larger water bodies. A few evidently develop in bog pools (exuviae were collected on 7 August in Brasenia Lake Bog) but this must be a rare occurrence. The species was well into its flight period in early August; all specimens collected were mature. Some observations on temporal activity were made at Kalmia Lake. On 9 August at 20:30h PDT a female oviposited in the algal scum covering the shoreline stones and males patrolled the water line until 21:30h when it was almost dark. On the mornings of 10 and 11 August males were active at 07:30h, 30 minutes before sunrise and matings oc- curred as early as 08:35h. Aeshna interrupta Walker A. interrupta is a common inhabitant of bog ponds on the peninsula. Most males observed flew along the margins of the larger ponds (e.g. Brasenia Lake, Danae Pond) although some larvae and ex- uviae were collected from bog creek pools. Oviposi- tion was noted on 31 July (Cassiope Lake) and copulation on 6 August (Danae Pond). Most specimens are patterned in the typical coastal form (“A. interrupta interrupta”), with lateral thoracic stripes broken into spots, although a few specimens of both sexes show only the posterior stripe broken. This material, like that examined by Cannings (1980) on the northern coast further emphasizes the invalidity of subspecies characterized by variation in thoracic stripes. Aeshna juncea (Linnaeus) In the study area A. juncea flies in similar habitats to those frequented by A. interrupta. In 48 J. ENTOMOL. Soc. BriT. COLUMBIA 80 (1983), DEc. 31, 1983 bogs it is more typical of the larger ponds than the sluggish creek pools, although it is more apt to develop in such pools than is A. interrupta. Indeed, A. juncea is more widespread than A. interrupta and adults and larvae were often found away from bogs (e.g. Headlands Pond, 9 August; The Throne, Mt. Doom, 9 August). On 10 August larvae were found under stones in a dry bog pool with those of Aeshna sitchensis, Somatochlora semicircularis and Leucorrhinia hudsonica. A. juncea emerges at least as early as mid July on the Brooks Peninsula (16 June, Prince Rupert [Walker 1958]) since oviposi- tion was noted on 31 July at Cassiope Lake. Emergence continued through early August (6 August, Danae Pond). At 14:15h on 12 August in Brasenia Lake Bog a female oviposited in wet moss clinging to a vertical rock surface on the edge of a drying creek pool. Aeshna palmata Hagen By the end of July on the peninsula A. palmata has begun emergence, but most specimens are evidently not sexually mature. Numbers of exuviae were collected in a wide range of habitats from rocky tarns and bog pools to stagnant creek and beach seepage pools. Few adults were captured and no females were seen. Aeshna sitchensis Hagen Detailed observations on the biology of A. sit- chensis on the Brooks Peninsula are summarized in Cannings (1982). This species is strictly an inhabi- tant of bogs, males patrolling only where shallow pools had dried during the recent warm weather. Females deposited eggs in the algal mat crusted on the bottom of the dried pools or sometimes in the lower parts of peaty, vertical pool banks. Larvae evidently can survive summer drought in these pool basins; active larvae, both half-grown and almost fully-grown, were found under stones embedded in the dry mud (Cannings 1982). Aeshna umbrosa Walker A. umbrosa is closely related to A. palmata and shares similar habitats on the peninsula. Adult males were especially prevalent along the deeply in- cised, sluggish and often intermittent streams dissecting the lowland bogs. Adults were not observed before 5 August, and no copulation or oviposition was noted. CORDULIIDAE Cordulia shurtleffi Scudder A single final instar larva of C. shurtleffi was col- lected in Carex along the shore of Kalmia Lake on 10 August. The absence of adults from the collec- tion indicates the species’ early flight period; in June and early July C. shurtleffi is probably one of the common species of the bogs and lakes of the Brooks Peninsula. Somatochlora albicincta (Burmeister) With Aeshna eremita, S. albicincta is the characteristic anisopteran of the shorelines of the larger lakes on the penunsula. It is also common over the large bog ponds, but seldom ventures in the drier parts of bogs inhabited by Aesha sitchensis and Somatochlora semicircularis. Oviposition was observed from 31 July (Cassiope Lake) to 11 August (Kalmia Lake). On 7 August at Brasenia Lake a female oviposited among the floating leaves of Nuphar polysepalum and Brasenia schreberi, drop- ping eggs into three or four centimetres of water over flocculent mud. At Kalmia Lake females oviposited both far out in the lake among Nuphar leaves and along the shore in two to three cen- timetres of water over algae-covered stones. In this location egg-laying occurred between 08:20h and 11:20h. At Cassiope Lake a pitfall trap set 60cm from the water’s edge and examined on 11 August contained a full-grown larva about to transform in- to an adult. Specimens of S. albicincta are extreme- ly large; a series of 18 males averages 51.4mm in total length (excluding anal appendages) and 33.4mm in hind wing length. Ranges of these two measurements are 49.0-53.0mm and 32.0-35.0mm respectively. Somatochlora semicircularis (Selys) Although usually tolerant of a wide variety of aquatic habitats, S. semicircularis on the Brooks Peninsula is restriced to bogs and especially to those parts of bogs containing small drying pools, runnels and streamlets. A male was captured “hilltopping” on the ridge above Cassiope Lake (700m) on 31 Ju- ly. Most oviposition occurs in mid-afternoon; ex- amples include a female dipping eggs in tiny pud- dles 10cm in diameter in a dry creek bed at Toebiter Bog (8 August) and another ovipositing in 10cm deep water over soft mud and algae in a bog pool 0.5m in diameter near Kalmia Lake (11 August). LIBELLULIDAE Leucorrhinia glacialis Hagen Only two males of L. glacialis were collected. One at Brasenia Lake on 7 August was less than three days old; the other, collected at Kalmia Lake on 1] August, was mature. The species is apparent- ly an uncommon inhabitant of bog ponds on the peninsula. Leucorrhinia hudsonica (Selys) L. hudsonica was the most collected of the genus in the study area, flying mainly in bogs, but also oc- curring in small, marshy lakes such as Cassiope Lake (31 July, exuviae). By early August on the peninsula, most of the species’ flight period is evidently over. Larvae were found in drying creek pools (Brasenia Lake Bog, 7 August) and under stones embedded in the mud of dried bog pools (Kalmia Lake Bog, 10 August). Leucorrhinia proxima Calvert One male of L. proxima was captured at Kalmia Lake, 11 August. Libellula quadrimaculata Linnaeus L. quadrimaculata occurred only in lowland bogs but was abundant around the larger ponds in these habitats. Between 16:15h and 16:45h on 5 August at Amos Creek Bog, pairs were mating and females ovipositing in the shallow water at the cen- J. ENTOMOL. Soc. Brit. COLUMBIA 80 (1983), DEc. 31, 1983 49 tre of a pool. At Kalmia Lake Bog on 11 August males first appeared at 09:30h and females began egg-laying at 11:15h. Sympetrum costiferum (Hagen) The presence of S. costiferum on the Brooks Peninsula is known from only two exuviae, found at Brasenia Lake on 7 August and at Danae Pond on 6 August. Although the species is known to emerge a month earlier than these dates in southern B.C. (Cannings and Stuart 1977), first emergence likely had just occurred. Sympetrum danae (Sulzer) Of Sympetrum species S. danae is perhaps the most characteristic of Sphagnum bogs, and in such habitats on the Brooks Peninsula it is abundant. In early August the species was well into its flight period although emergence continued throughout the study (Danae Pond, 3 August; Brasenia Lake, 7, 12 August). Oviposition always occurred in tandem flight. Sympetrum occidentale Bartenev S. occidentale is likely a rare species on the Brooks Peninsula as it is not typical of cool climates. Larvae only were collected (Cassiope Lake, 31 July; Brasenia Lake, 7 August; Kalmia Lake Bog, 10 August); emergence evidently had not yet begun. Most initial emergence in southern B.C. does not occur until after the third week of July (Cannings and Stuart 1977). Sympetrum madidum (Hagen) The distinctive exuviae of S. madidum were located at Danae Pond on 6 August. No adults were seen. The species is usually local and not found in large numbers; it would be easily overlooked if emergence had just occurred. Sympetrum pallipes (Hagen) S. pallipes was common in bogs throughout the study. Most of the population was mature, but a teneral female was recorded at Danae Pond on 6 August. Mating and oviposition occurred throughout the study. On 12 August at Brasenia Lake Bog 50 per cent of the oviposition was done by lone females, 25 per cent by tandem pairs and 25 per cent by females being guarded by males close by. Eggs were dropped from a height of 5 to 15 cm into dry parts of the bog dominated by Carex and Sphagnum. Oviposition peaked about 14:00h. DISCUSSION Twenty species in eight genera and five families were collected, four of the species only as larvae or exuviae. This species total is 25 percent of the pro- vincial fauna. Although the study lasted only two weeks, it encompassed the height of the probably short flying period of most local species. Consistent- ly fine weather produced efficient collecting, and all suitable habitats were sampled. We estimate that 80 percent of the total local fauna was observ- ed. In comparison, similar habitat in the Queen Charlotte Islands has to date produced only 13 species while a greater range of habitats and much more extensive collecting on southern Vancouver Island and the Lower Mainland has accounted for 53 species. The dragonfly fauna of the central and northern coast is predominantly Boreal and Holarctic in distribution with few species having Western, Southwestern or Southern Transcontinental ranges. Table 1 illustrates this zoogeographic pattern. The Holarctic and Boreal components decrease southward and the percentage of species originating in strictly western and southern transcontinental regions increases southwards. The Queen Charlotte Island fauna is completely northern in origin while the Brooks Peninsula fauna is 85 percent so compos- ed (Cordilleran species are a boreal element confin- ed to the western mountains while the Western ele- ment includes species with Great Basin, Sonoran or Pacific Coastal origins). Species abundant on the Brooks Peninsula but absent from the Queen Charlotte Islands despite large amounts of suitable habitat include the Boreal Aeshna interrupta, the Cordilleran Somatochlora semicircularis and the Western Sympetrum pallipes. On the Brooks Penin- sula the three species of the Western faunal element (Sympetrum madidum, S. occidentale and S. pallipes) are probably near their northern limit on the cool, wet outer coast. TABLE 1. Percentage composition of the Odonata fauna of various west coast regions in British Columbia based on species distribution. Queen Charlotte Islands (n=13) Brooks Peninsula (n=20) 15 5 10 7 Lower Mainland 10 25) (n=51) Holarctic Boreal Cordilleran Western Southern Transcontinental <= | poe foe foe oe poe foe * ie: 50 J. ENTOMOL. Soc. BriT. COLUMBIA 80 (1983), DEc. 31, 1983 TABLE 2. Ecological separation of species observed as adults. Species (in approximate order of abundance) large ponds proxima small pools runnels, often sluggish creek pools cyathigerum Mountain Ponds palmata Upper Beach Seepage Pools Aeshna umbrosa Table 2 illustrates the ecological separation of species observed as adults. Some species such as Lestes disjunctus and Enallagma cyathigerum or even Aeshna juncea have wide environmental tolerances while others, Aeshna eremita, A. sitchen- sis and Somatochlora semicircularis, for example, are restricted to circumscribed habitats. Such spatial separation of species may be even more im- portant in cool, often inclement climates such as is found on the Brooks Peninsula than in the more amenable ones to the south and east. It appears that many species here (e.g. Lestes disjunctus, Aeshna palmata, Sympetrum costiferum) begin adult life a month or more later than they do on the south coast or at the same latitude in the B.C. Interior. This shortening of the community’s overall flight period Lestes disjunctus, Sympetrum danae, Enallagma cyathigerum, Aeshna interrupta, Libellula quadrimaculata, Aeshna juncea, Somatochlora albicincta, Leucorrhinia hudsonica, L. glacialis, L. Lestes disjunctus, Sympetrum pallipes, Aeshna sitchensis, Sympetrum danae, Somatochlora dry semicircularis Aeshna umbrosa, A. juncea, A. interrupta, A. palmata, Somatochlora semicircularis Aeshna eremita, Somatochlora albicincta, Enallagma Lestes disjunctus, Enallagma cyathigerum, Aeshna juncea, A. interrupta, Somatochlora albicincta, Aeshna results in a greater overlap of these restricted specific flight periods, perhaps increasing both intra- and interspecific competition. At the same time the mild but wet climate pro- duces a long larval growing season which may help to explain the large size of some adult specimens, notably those of Somatochlora albicincta. It has long been known that this species reaches a greater size in British Columbia than in other parts of Boreal America (Walker and Corbet 1975). Specimens from high elevations in southern B.C. and from sea level in Alaska are considerably smaller than those from sea level on the central B.C. coast (Whitehouse 1941); those from the Brooks Peninsula are as big as, or bigger than, any previously recorded. REFERENCES Cannings, R. A. 1982. Notes on the biology of Aeshna sitchensis Hagen (Anisoptera:Aeshnidae). Odonatologica 11 (3):219-223. _______and K. M. Sutart. 1977. The Dragonflies of British Columbia. B.C. Provincial Museum Handbook No. 35, 254pp. Cannings, S. G. 1980. New distribution records of Odonata from northwestern British Columbia. Syesis 13:13-15. J. ENTOMOL. SOC. BRIT. COLUMBIA 80 (1983), DEc. 31, 1983 51 Scudder, G. G. E., R. A. Cannings, and K. M. Stuart. 1976. An annotated checklist of the Odonata (Insec- ta) of British Columbia. Syesis 9:143-162. Walker, E. M. 1953. The Odonata of Canada and Alaska, Vol. 1. Univ. Toronto Press, Toronto. 292pp. 1958. The Odonata of Canada and Alaska, Vol. 2. Univ. Toronto Press, Toronto. 318pp. and P. S. Corbett. 1975. The Odonata of Canada and Alaska, Vol. 3. Univ. Totonto Press, Toron- to. 307pp. Whitehouse, F. C. 1941. British Columbia dragonflies (Odonata) with notes on distribution and habits. Amer. Midl. Naturalist 26:488-557. THE APHIDS (HOMOPTERA:APHIDIDAE) OF BRITISH COLUMBIA ll. FURTHER ADDITIONS A. R. FORBES AND C. K. CHAN Research Station, Agriculture Canada Vancouver, British Columbia, V6T 1X2 ABSTRACT Ten species of aphids and new host records are added to the taxonomic list of the aphids of British Columbia. INTRODUCTION The previous seven lists of the aphids of British Columbia (Forbes, Frazer and MacCarthy 1973; Forbes, Frazer and Chan 1974; Forbes and Chan 1976, 1978, 1980, 1981; Forbes, Chan and Foottit 1982) recorded 341 species of aphids collected from 708 different host plants. This comprises 1298 aphid-host plant associations. The present list adds 10 aphid species (indicated with an asterisk in the list) and 78 aphid-host plant associations to the previous lists. Thirty-five of the new aphid-host plant associations are plant species not in the previous lists. The additions bring the number of known aphid species in British Columbia to 351. Aphids have now been collected from 743 different host plants and the total number of aphid- host plant associations is 1376. The names of aphids are in conformity with Eastop and Hille Ris Lambers (1976) and are ar- ranged alphabetically by species. The location of each collection site can be determined from the tables of localities in the previous papers. LIST OF SPECIES ADIANTI (Oestlund), SITOBION Pellaea glabella var. simplex: Vancouver (CDA), Jul 14/82. ALBIFRONS Essig, MACROSIPHUM Lupinus arboreus: Vancouver (UBC), Jul 15/83. Lupinus nootkatensis var. nootkatensis: Van- couver (UBC), Jul 15/83. AMERICANUM (Riley), ERIOSOMA Ulmus americana: Kelowna, Jun 12/82, Aug 22/81. AQUILEGIAE (Essig), KAKIMIA Aquilegia vulgaris: Vancouver (UBC), Jun 11/79. ASCALONICUS (Doncaster), MYZUS Coluta australis: Vancouver (UBC), May 8/81. Erigeron speciosus var. speciosus: Vancouver (UBC), May 8/81. Potentilla gracilus var. glabrata: Vancouver (UBC), May 8/81. Pulmonaria officinalis: Vancouver (UBC), Aug 24/79. AVENAE (Fabricius), SITOBION Hordeum vulgare: Vancouver (CDA), Dec 1/80. BETAE Doane, PEMPHIGUS Lactuca sativa: Abbotsford, Aug 23/82. BRAGGII (Gillette), CINARA Picea sitchensis: Terrace, Aug 26/82. BRASSICAE (Linnaeus), BREVICORYNE Brassica ‘Osaka Red’: Vancouver (UBC), Oct 2/51: *CALIFORNICA Hille Ris Lambers, NEARCTAPHIS Sorbus aucuparia: Vancouver, Jul 2/81. CALIFORNICUM (Clarke), MACROSIPHUM Salix triandra: Vancouver (UBC), Jul 15/83. CERASI (Fabricius), MYZUS Galium aparine: Cloverdale, Aug 24/82. Nasturtium officinale: Vancouver, Mar 1/82. CIRCUMFLEXUM (Buckton), AULACORTHUM Fumaria officinalis: Vancouver (UBC), Aug 18/83. Pilularia globulifera: Vancouver (UBC), Jun 24/81, Jul 16/81. Scheffera octophylla: Vancouver, May 25/81. CRACCIVORA Koch, APHIS Picea sp.: Surrey, Aug 23/82. CRATAEGARIUS (Walker), OVATUS Origanum vulgare: Vancouver, Dec 7/81. 52 J. ENTOMOL. Soc. Brit. CoLumsia 80 (1983), DEc. 31, 1983 CYNOSBATI Oestlund, KAKIMIA Ribes divaricatum: Vancouver 30/82, May 8/78, May 13/82. Ribes lacustre: Vancouver (UBC), Apr 26/82, May 28/82. DAPHNIDIS Borner, MACROSIPHUM Daphne x burkwoodii ‘Somerset’: Vancouver (UBC), June 24/80. Daphne laureola: Vancouver (UBC), Jan 18/80, Mar 13/81, May 4/79, May 22/81, Jun 16/81, Jul 16/79, Aug 12/80. EQUISETI Holman, SITOBION Equisetum arvense: Vancouver, Jun 21/83. EUPHORBIAE (Thomas), MACROSIPHUM Asparagus densiflorus ‘Sprengeri’: Vancouver (CDA), Jun 21/83. Asparagus officinalis: Vancouver (CDA), Jun 21/83. Beta vulgaris: Vancouver (CDA), Jun 21/83. Brassica oleracea acephala group: Vancouver (CDA), Aug 15/83. Capsella bursa-pastoris: Vancouver (CDA), Aug 15/83. Citrus maxima: Vancouver (CDA), Jun 21/83. Cucumis sativa; Vancouver, Aug 15/82. (UBC), Apr Fragaria vesca ‘Semperflorens’: Vancouver (CDA), Jun 21/83. Hordeum vulgare: Vancouver (CDA), June 21/83. Lycopersicon lycopersicum: Vancouver (CDA), Jul 15/82. Rosa ‘Beauty Secret’: Vancouver (CDA), Jun 20/83. Verbena ‘Ideal Florist’: Vancouver (CDA), May 20/83. Verbesina encelioides: Vancouver (CDA), Jul 16/83. FABAE Scopoli, APHIS Apocynum androsaemifolium: (UBC), Jun 23/81. *FABAE MORDVILKOI Borner & Janisch, APHIS Pseudotsuga menziesii: Surrey, Aug 23/82. FARINOSA Gmelin, APHIS Salix acutifolia ‘pendulifolia’: Vancouver (UBC), Jul 22/81: FRAGARIAE (Walker), SITOBION Bromus ciliatus: Vancouver (UBC), Jul 3/79. Poa pratensis ssp. agassizensis: Vancouver (UBC), Jun 13/79. GALEOPSIDIS (Kaltenbach), CRYPTOMYZUS Ribes nigrum: Cloverdale, May 19/83. GENTNERI (Mason), FIMBRIAPHIS Crataegus laevigata ‘Paul’s Scarlet’: Vancouver, May 30/83. HELICHRYSI (Kaltenbach), BRACHYCAUDUS Erigeron speciosus var. speciosus: Vancouver (UBC), May 8/81. HUMULI (Schrank), PHORODON Humulus lupulus: Vancouver, Jun 21/83. Vancouver LACTUCAE (Linnaeus), HYPEROMYZUS Sonchus arvensis: Vancouver, Aug 22/80. LONICERAE (Siebold), RHOPALOMYZUS Dactylis glomerata: Cloverdale, Aug 27/82; Sur- rey, Aug 23/82. *LUDOVICIANAE (Oestlund), MACROSIPHONIELLA Moericke yellow pan water trap: Summerland, Jul 2/76. MAIDIS (Fitch), RHOPALOSIPHUM Zea mays: Vancouver (CDA), Aug 18/83. *MUSAE (Schouteden), RHOPALOSIPHUM Dactylis glomerata: Surrey, Aug 23/82. NERVATA ARBUTI (Davidson), WAHLGRENIELLA Paxistima myrsinites: Vancouver (UBC), Jul 6/81. *OBLIQUUS (Cholodkovsky), MINDARUS Picea sp.: Surrey, Aug 23/82. ORNATUS Laing, MYZUS Arnica chamissonis: Vancouver (UBC), May 26/81. Parahebe catarractae: Vancouver (UBC), May 26/81. PADI (Linnaeus) RHOPALOSIPHUM Ginkgo biloba: Agassiz, Sep 21/82. Zea mays: Vancouver (CDA), Aug 18/83. PERSICAE (Sulzer), MYZUS Calendula officinalis: Vancuver (UBC), May 8/81. Lactuca sativa: Cloverdale, Aug 9/82, Aug 24/82. Rumex obtusifolius spp. obtusifolius: Vancouver (CDA), Jun 25/82. PISUM (Harris), ACYRTHOSIPHON Robinia pseudoacacia: Vancouver (UBC), Jun 14/79. POMI de Geer, APHIS Crataegus laevigata ‘Paul’s Scarlet’: Vancouver, May 30/83. Sorbus aucuparia: Vancouver, Jul 2/81. RHAMNI (Clarke), SITOBION Rhamnus purshiana: Vancouver (UBC), Jun 17/83. *RHOKALAZA (Tissot & Pepper), ILLINOIA Leucothoe fontanesiana: Vancouver (UBC), Jul 15/81. RIBISNIGRI (Mosley), NASONOVIA Hieracium scouleri var. scouleri: (UBC), Aug 21/82, Oct 1/82. Lactuca sativa: Abbotsford, Aug 8/82. ROSAE (Linnaeus), MACROSIPHUM Rosa ‘Golden Showers’: Vancouver (UBC), Nov 12/80. Rosa ‘Handel’: Vancouver (UBC), Nov 12/80. Rosa ‘Lichtkonigin Lucia’: Vancouver (UBC), Nov 12/80. *“RUBICOLA (Oestlund), ILLINOIA Rubus idaeus ssp. melanolasius: Terrace, Jul 31/24 (MacGillivray 1958). Vancouver J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DEC. 31, 1983 oo RUMEXICOLENS (Patch), BRACHYCAUDUS Rumex obtusifolius ssp. obtusifolius: Abbotsford, Jun 23/82. *SCHLINGERI Hille Ris Lambers GLABROMYZUS Carex capitata ssp. capitata: Vancouver (UBC), Jul 22/78. Carex leporina: Vancouver (UBC), Jul 22/78. Carex limosa: Vancouver (UBC), Jul 22/78. Juncus effusus var. pacificus: Vancouver (UBC), Jul 22/78. Luzula arctica ssp. latifolia: Vancouver (UBC), May 25/79. Luzula nivea: Vancouver (UBC), May 13/81, May 22/79, May 29/79, May 30/81, Jun 11/79, Jun 21/79, Jul 26/79. SOLANI (Kaltenbach), AULACORTHUM Apocynum androsaemifolium: Vancouver (UBC), Jun 2/81, Jun 24/81. Lactuca sativa: Cloverdale, Jun 14/82. Liquidambar styraciflua: Vancouver May 22/81, Jun 2/81. Tricyrtis hirta: Vancouver (UBC), Sep 13/78. SONCHI (Linnaeus), UROLEUCON Lactuca sativa: Abbotsford, Aug 8/82. SPIRAECOLA (Patch), ILLINOIA Spiraea thunbergii: Vancouver (UBC), Apr 3/18, Jun 22/79. STANLEYI Wilson, MACROSIPHUM Sambucus racemosa ssp. pubens var. ar- borescens: Vancouver (UBC), Jun 27/83, Jul 15/83. STAPHYLEAE (KOCH), RHOPALOSIPHONINUS Apocynum androsaemifolium: Vancouver (UBC), Jun 24/81. Brassica pekinensis: Vancouver (CDA), Aug (UBC), *STELLARIAE Theobald, MACROSIPHUM Apium graveolens: Vancouver (CDA), Oct 1/81. Beta vulgaris: Vancouver (CDA), Aug 15/83. Capsella bursa-pastoris: Vancouver (CDA), Oct 14/82. Dianthus alpinus: Vancouver (UBC), Jun 9/80. Dianthus barbatus: Vancouver (CDA), Aug 15/83. Dianthus ‘Scarlet Luminette’: Vancouver (UBC), Aug 31/82, Oct 2/81. Dianthus sp.: Vancouver (UBC), Jun 10/80, Jun 15/81, Aug 13/82. TARAXACI (Kaltenbach), UROLEUCON Taraxacum officinale: Vancouver (UBC), Sep 14/79. TESTUDINACEUS (Fernie), PERIPHYLLUS Aesculus hippocastanum: Vancouver, May 31/79, Jun 14/79; Vancouver (UBC), May 25/79. *ULMI (Linnaeus), ERIOSOMA Ulmus americana: Kelowna, Aug 22/81. URTICA Essig, AMPHOROPHORA Urtica dioica ssp. gracilis var. lyallii: Ladner, Jun 6/81. UTRICULARIA (Passerini), GEOICA Gramineae: Wilson Creek, Jun 4/81, Jul 3/81, Jul 9/81, Jul 27/81. WOODSIAE Robinson, SITOBION Woodsia scopulina var. scopulina: Vancouver (UBC), Jul 7/81. *Aphid species not in the previous lists. ACKNOWLEDGEMENTS The authors gratefully acknowledge the continu- ing help of Drs. V. F. Eastop and R. L. Blackman, British Museum (Natural History), London, England, and of Dr. A. G. Robinson, University of 18/83. Manitoba, Winnipeg, with identifications and Yucca sp.: Vancouver, Aug 21/83. other advice. REFERENCES Eastop, V. F., and D. Hille Ris Lambers. 1976. Survey of the world’s aphids. Dr. W. Junk b.v., Publisher, The Hague. Forbes, A. R., and C. K. Chan. 1981. The aphids (Homoptera: Aphididae) of British Columbia. 9. Further additions. J. ent. Soc. Brit. Columbia 78:53-54. Forbes, A. R., and C. K. Chan. 1980. The aphids (Homoptera: Aphididae) of British Columbia. 8. Further additions. J. ent. Soc. Brit. Columbia 77:38-42. Forbes, A. R., and C. K. Chan. 1978. the aphids (Homoptera: Aphididae) of British Columbia. 6. Further additions. J. ent. Soc. Brit. Columbia 75:47-52. Forbes, A. R., and C. K. Chan. 1976. The aphids (Homoptera: Aphididae) of British Columbia. 4. Further additions and corrections. J. ent. Soc. Brit. Columbia 73:57-63. Forbes, A. R., C. K. Chan and R. Foottit. 1982. The aphids (Homoptera: Aphididae) of British Columbia. 10. Further additions. J. ent. Soc. Brit. Columbia 79:75-78. Forbes, A. R., B. D. Frazer and C. K. Chan. 1974. The aphids (Homoptera: Aphididae) of British Colum- bia. 3. Additions and corrections. J. ent. Soc. Brit. Columbia 71:43-49. Forbes, A. R., B. D. Frazer and H. R. MacCarthy. 1973. The aphids (Homoptera: Aphididae) of British Columbia. 1. A basic taxonomic list. J. ent. Soc. Brit. Columbia 70:43-57. MacGillivray, M. E. 1958. A study of the genus Masonaphis Hille Ris Lambers, 1939 (Homoptera, Aphididae). Temminckia 10:115-120. 54 J. ENTOMOL. Soc. BRIT. COLUMBIA 80 (1983), DEc. 31, 1983 LIBELLULA SUBORNATA (ODONATA:LIBELLULIDAE) IN CANADA ROBERT A. CANNINGS Entomology Division British Columbia Provincial Museum Victoria, B.C. V8V 1X4 ABSTRACT The dragonfly Libellula subornata, a species of arid southwestern North America, is reported from Canada for the first time. Specimens collected over a number of years at Nanaimo, British Columbia, have recently come to light. Features that distinguish this species from the common Libellula forensis and L. lydia are noted. Libellula subornata (Hagen) is a dragonfly of southwestern North America closely related to the widespread Libellula lydia Drury. Both species are placed by some workers in a separate genus, Plathemis Hagen. Needham and Westfall (1955) note that L. subornata normally is found around swales and seepage pools in desert and semidesert areas. They record the species from Chihuahua and Sonora in northern Mexico and from Arizona, California, Colorado, Kansas, Nebraska, Nevada, New Mexico, Texas and Utah in the United States. British Columbia also is mentioned in the distribu- tion, although no explanation is given for this sur- prising inclusion. More recently the species was recorded in Oklahoma (Bick and Bick 1957) and in southeastern Oregon (Kormondy 1960). Dennis Paulson (pers. comm.) has collected over 4500 dragonfly specimens from all parts of Washington State since 1967 without ever seeing this species. When Richard Guppy of Thetis Island, British Columbia died in 1980, some of his correspondence was deposited in the British Columbia Provincial Museum. From this source I learned that for many years he had collected dragonflies for Carl Cook of Center, Kentucky. I also discovered that he had supplied Cook with specimens of L. subornata from Nanaimo, B.C. These records are the basis for the inclusion of British Columbia in the distribution given for L. subornata in Needham and Westfall (1955). The species was not mentioned in Cannings and Stuart (1977) as it was not included in Walker and Corbet (1975) and was not considered a likely candidate for the Canadian list. Carl Cook (in litt.) explains fur- ther: “Walker knew about the record because he had the specimens on loan for a time during the period he was working on the early volumes of the Odonata of Canada and Alaska, but I think Corbet did not because he probably overlooked it in Needham and Westfall and had not yet started to correspond with him (Westfall) when he took over work on Volume III.” Guppy collected at least a dozen specimens of L. subornata between about 1950 and 1972, most of which are scattered in private collections. Walker’s collection in the Royal Ontario Museum does not contain any specimens (G. B. Wiggins, in litt.). Cook still has a single male collected by Richard Guppy at Nanaimo on 28 June 1969. Another male which Cook donated to the B.C. Provincial Museum has the same data except for the date, 5 Ju- yal Oz. Since it is well known that during his career Richard Guppy collected only on southern Van- couver Island and adjacent Gulf Islands, it is dif- ficult to dismiss the record of L. subornata from Nanaimo as the result of a mixup of Guppy’s specimens and data. Similarly, since the specimens were sent to Cook over a period of more than 20 years, a mixup of his own specimens with Guppy’s data seems impossible. Although surprising, the evidence suggests that L. swbornata was collected at Nanaimo, 800 km northwest of its normal range, in a habitat very unlike its normal one. Moreover, the fact that specimens were captured over a long period within a small area suggests not only that the occurrence of L. subornata on southern Vancouver Island is not accidental, but also that the species may breed there. Until further specimens are col- lected, however, the records should be accepted with caution. On 2 July 1982 I visited the locality near Nanaimo where, according to his colleagues, Richard Guppy probably collected the specimens. I saw no L. subornata specimens. L. subornata males key to L. lydia in most keys which include only the latter (e.g. Walker and Cor- bet 1975; Cannings and Stuart 1977). In these cases females will key to L. forensis, except in keys using Plathemis as a generic name in which case females will not key satisfactorily. Larvae key to L. lydia. L. subornata males can be distinguished from those of L. lydia by several characters. The bifid process on the sternum of abdominal segment 1 is divided only halfway to its base by a shallow V- shaped cleft. The dark pigment on the venter of the labium forms a definite median stripe while in L. lydia it is mostly basal and diffuse. Wing markings are distinctive. In L. subornata the middle third of the brown nodal band is paler than the rest of the band and almost the entire area between this band J. ENTOMOL. Soc. brit. CoLuMBIA 80 (1983), DEc. 31, 1983 ay) and the wingbase, excluding the basal brown spot, hooks covered by spiniform setae on the same is pruinose white. In L. lydia the nodal band is segments (Levine 1957). uniformly brown and the basal white area is much less extensive. Females of L. swbornata do not have ACKNOWLEDGEMENTS the dark wingtips of L. lydia females and unlike I thank Mr. Carl Cook and Dr. Glenn Wiggins those of L. forensis have the distal dark wing spot _ for information concerning the Canadian specimens divided by a pale area. L. subornata larvae have of L. subornata. Drs. Philip Corbet and Dennis blunt, hairy dorsal hooks on abdominal segments 3 Paulson read the manuscript. to 6 while those of L. lydia have sharp, thorn-like REFERENCES Bick, G. H. and J. C. Bick. 1957. The Odonata of Oklahoma. Southw. Nat. 2: 1-8. Cannings, R. A. and K. M. Stuart. 1977. The dragonflies of British Columbia. British Columbia Provincial Museum Handbook No. 35, Victoria. 254 pp. Kormondy, E. J. 1960. New North American records of anisopterous Odonata. Ent. News 71: 121-130. Levine, H. R. 1957. Anatomy and taxonomy of the mature naiads of the dragonfly genus Plathemis (Family Libellulidae). Smithson. Misc. Coll. 134(11): 1-28. Needham, J. G. and M. J. Westfall. 1955. A manual of the dragonflies of North America (Anisoptera) in- cluding the Greater Antilles and the Provinces of the Mexican border. University of California Press, Berkeley. 615 pp. Walker, E. M. and P. S. Corbet. 1975. The Odonata of Canada and Alaska. III. University of Toronto Press, Toronto and Buffalo. 307 pp. OF Bin 2 SCIENTIFIC WRITING 2 B FOR 2—Z= GRADUATE STUDENTS This manual is a “must” for those who would introduce courses of in- struction in scientific writing into university graduate schools. The first nine chapters provide the essentials for “Writing a Journal Article,” and the remaining five chapters cover “Related Topics” in scientific com- munication. CONTENTS: 1. Clearing Away the Underbrush ¢ 2. The Ground Plan ¢ 3. The Master Plan e 4. The First Draft * 5. The First Revision: Structural Alterations © 6. Further Revision: Polishing the Style ¢ 7. Editing Assignments © 8. The Final Steps © 9. Re- sponding to the Editor ¢ 10. Design of Tables and Figures @ 11. Prep- aration for Writing the Doctoral Thesis ¢ 12. Writing a Research Pro- ject Proposal e 13. Oral Presentation of a Scientific Paper e 14. Principles and Practices in Searching the Scientific Literature Paperbound; ISBN: 0-914340-01-8; Published 1968, reprinted 1983; Trim size: 6 x 9 inches; 190 pages Regular Price: $9.75 (10% discount on 10 or more copies delivered to one address) CBE Member Discount Price: $8.75 (single copy paid by personal check) Terms of Sale: All sales final; no returns. Prepayment required; U.S. currency drawn on a US. bank. Price includes BOOK RATE postage. For faster delivery--first class, air mail, or UPS available at additional charge (book weight, 11.5 oz). Maryland residents, please add 5% sales tax. COUNCIL OF BIOLOGY EDITORS, INC. 9650 Rockville Pike, Bethesda, MD 20814 56 J. ENTOMOL. Soc. Brit. CoLuMBIA 80 (1983), DEc. 31, 1983 NOTICE TO CONTRIBUTORS This society has no support except from subscriptions. It has become necessary to institute a page charge. This has now been set at $35.00. The page ;charge includes all extras except coloured illustrations, provided that such extras do not comprise more than 40% of the published pages. Coloured illustrations will be charged directly to the author. Authors, not attached to universities or official institutions, who must pay these charges from their personal funds and are unable to do so, may apply for assistance when submitting a manuscript. Reprints are sold only in even hundreds and at the following prices: Number of pages 1-4 5-8 9212 . 213-16 17-20 21-24 25-28 First 100 copies $41.00 58.50 81.00 103.00 131.00 163.00 199.00 Each extra 100 9.00 12.00 15.00 18.00 21.00 24.00 27.00 Author’s discounts (up to 40%) may be granted to authors who certify at the time of ordering that they are buying reprints at personal expense. Authors ordering personal reprints in addition to those ordered by an institution will be billed at the rate for extra hundreds. Membership is open to anyone with an interest in entomology. Dues are $8.00 per year; for students $4.00. Papers for the Journal need not have been presented at meetings of the Entomological Society of British Columbia, nor is it mandatory, although preferable, that authors be members of this society. The chief condition for publication is that the paper have some regional origin, interest, or application. Contributions should be sent to: H. R. MacCarthy 6660 N.W. Marine Drive Vancouver, B.C. V6T 1X2 Manuscripts should be typed double-spaced on one side of white, line-spaced numbered paper if possible, leaving generous margins. The original and two copies, mailed flat, are required. Tables should be on separate, numbered sheets, with the caption on the sheet. Captions for illustrations should also be on separate numbered sheets, but more than one caption may be on a sheet. Photographs should be glossy prints of good size, clarity and contrast. Line drawings should be in black ink on good quality white paper. The style, abbreviations and citations should conform to the Style Manual for Biological Journals published by the American Institute of Biological Sciences. BACK NUMBERS Back numbers of this journal are available from the Secretary-Treasurer, from volume 45 (1949) to the present, at $8.00 per volume. Certain earlier back numbers are also available, but only on special request to the Secretary-Treasurer. Address inquiries to: Dr. G. E. Miller, Secretary-Treasurer Pacific Forest Research Centre 506 West Burnside Road Victoria, B.C. V8Z 1M5 . ISSN 40071-0733 J Oo URN A L | of the ENTOMOLOGICAL et SOCIETY of : BRITISH COLUMBIA Issued December 31, 1984 . S. Lindgren, J. D. Swé a cae monitoring the et ehscake moth (Lepidoptera: a . Angerilli & J. A. McLean — Windtunnel & field observations of western spruce budworm responses to pheromone-baited traps L. Shore & J. A. McLean — The effect of height of pheromone-baited traps on catches of the ambrosia beetle, Trypodendron lineatum . I. Alfaro & T. L. Shore — Color video tape to record forest defoliation . W. Bishop, J. L. Blackmer & C. R. Baire — Observations on the biology of Prionus californicus on hops in Idaho GENERAL . G. Davis, L. M. McDonough & K. S. Pike — Attraction of male Fumibotys fumalis to females of the species . P. Beirne — Biological control of the European fruit lecanium, Lecanium tiliae (Homoptera: Coccidae) in British Columbia . M. Humble — Emergence behaviour of Phobocampe sp. (Hymenoptera: Ichneumonidae), a larval eudoparasitoid of Operophtera spp. (Lepidoptera: Geometridae) . 1. Alfaro, T. L. Shore & E. Wegwitz — Defoliation & mortality caused by western spruce budworm: variability in a Douglas-fir stand . H. Holsten — Factors of susceptibility in spruce beetle attack on white spruce in Alaska . E. Miller, A. F. Hedlin & D. S. Ruth — Damage by two Douglas-fir cone & seed insects: correlation with cone crop size . Mohamad & P. C. Oloffs — Rearing non-diapausing western spruce budworm on pre- mixed artificial diet . R. Wilkinson — Hosts & distribution of Rocky Mountain wood ticks (Dermacentor andersoni) at a tick focus in British Columbia rangeland . R. Forbes & C. K. Chan — The aphids (Homoptera: Aphididae) of British Columbia 12. Further additions . G. E. Scudder & D. M. McE. Kevan — A check-list of the Orthopteroid insects recorded from British Columbia . West, C. D. Doudale & R. A. Ring — A revised checklist of the spiders (Araneae) of British Columbia BOOK REVIEW NOTICE TO CONTRIBUTORS ISSN 40071-0733 J O U RNAL of the ENTOMOLOGICAL SOCIETY of BRITISH COLUMBIA Vol. 81 Issued December 31, 1984 ECONOMIC B. S. Lindgren, J. D. Sweeney & J. A. McLean — Comparative evaluation of traps for monitoring the Douglas-fir tussock moth (Lepidoptera: Lymantriidae) ............ 3 N. Angerilli & J. A. McLean — Windtunnel & field observations of western spruce budworm responses to pheromone-baited traps .............. 0.0.0 eee ee eee eens 10 T. L. Shore & J. A. McLean — The effect of height of pheromone-baited traps on catches of the ambrosia beetle, Trypodendron lineatum .............0. 000 cece eee 17 R. I. Alfaro & T. L. Shore — Color video tape to record forest defoliation ........... 19 G. W. Bishop, J. L. Blackmer & C. R. Baire — Observations on the biology of Prionus californicus7on hops in) [dah :.2 505... 96 6 Sy ees 1.0 a ds ein owe (aed lne ee ene”: 20 GENERAL H. G. Davis, L. M. McDonough & K. S. Pike — Attraction of male Fumibotys fumalis to fenraleszOf, Ee Peles 2.52 2:2 aren oe ae ve ewe etee ed Wiad ak wide Ren Ee eo ene Sia 25 B. P. Beirne — Biological control of the European fruit lecanium, Lecanium tiliae (Homoptera: Coccidae) in British Columbia .................. 00.0000 eee eee eee 28 L. M. Humble — Emergence behaviour of Phobocampe sp. (Hymenoptera: Ichneumonidae), a larval eudoparasitoid of Operophtera spp. (Lepidoptera: CeGMetnidae) en macs ei Re Sal ales Sater Ase 4 wallstis Atk dng BA eR anaes 29 R. I. Alfaro, T. L. Shore & E. Wegwitz — Defoliation & mortality caused by western spruce budworm: variability in a Douglas-fir stand ...................0. 00.0000 33 E. H. Holsten — Factors of susceptibility in spruce beetle attack on white spruce in Alaska ee ee ne ee ee en ee eee ee re ey Ce 39 G. E. Miller, A. F. Hedlin & D. S. Ruth — Damage by two Douglas-fir cone & seed insects: correlation with cone crop size .............. 02. cece eee eee eens 46 R. Mohamad & P. C. Oloffs — Rearing non-diapausing western spruce budworm on pre- AUDI ESCA CTEM CL AN CLC Urs lactose tes seco hoe Id iter hd iia aateenel Meets, oy PR Wy petal oa ack cae 51 P. R. Wilkinson — Hosts & distribution of Rocky Mountain wood ticks (Dermacentor andersoni) at a tick focus in British Columbia rangeland .....................-.. 57 A. R. Forbes & C. K. Chan — The aphids (Homoptera: Aphididae) of British Columbia UZ EGC AUGIUIONS rea elec Ae ie a nae ee eee ce anu ee Mad Mile ne, oe Gee 72 G. G. E. Scudder & D. M. McE. Kevan — A check-list of the Orthopteroid insects recorded from British Columbia ................ 0... cece ec cece eee e ene neenes 76 R. West, C. D. Doudale & R. A. Ring — A revised checklist of the spiders (Araneae) of BritisheColumbiagmea es, 2c.) serene cee nana a Ror ce ee a aan ek ae eee eee 80 BOOK HEV MWe ee Sota a uchk Hi eee el Ast ene hoa ie. CAN GS clam rere tele hor ane 32 J. ENTOMOL. Soc. BriT. COLUMBIA 81 (1984), DEc. 31, 1984 DIRECTORS OF THE ENTOMOLOGICAL SOCIETY OF BRITISH COLUMBIA FOR 1984-1985 President Nello Angerilli Agriculture Canada, Summerland President-Elect Rob Cannings B.C. Provincial Museum, Victoria Past President Richard Ring University of Victoria, Victoria Secretary- Treasurer Gordon Miller Pacific Forest Research Centre, Victoria Editorial Committee (Journal) H. R. MacCarthy R. Ring A. R. Forbes Editor (Boreus) R. Cannings Directors J. Harris (2nd) B. Roitberg (2nd) J. Sweeney (Ist) S. Lindgren (Ist M. Isman (Ist) Hon. Auditor W. T. Cram Regional Director of National Society R. Cannings B.C. Provincial Museum, Victoria J. ENTOMOL. Soc. Brit. COLUMBIA 81 (1984), DEc. 31, 1984 COMPARATIVE EVALUATION OF TRAPS FOR MONITORING THE DOUGLAS-FIR TUSSOCK MOTH (LEPIDOPTERA:LYMANTRIIDAE) B.S. LINDGREN! J. D. SWEENEY AND J. A. MCLEAN Faculty of Forestry Department of Forest Sciences University of British Columbia Vancouver, B.C. V6T 1W5 Canada ABSTRACT Delta sticky traps consistently caught at least as many Douglas-fir tussock moths as did five other trap types in field experiments. Omni-directional non-sticky traps based on the Lindgren multiple funnel trap were relatively successful, but highly variable. Wind tunnel tests with a simulated pheromone (= titanium tetrachloride smoke), showed that plums generated from Lindgren 2-funnel traps contaminated the exterior surfaces of the traps and inhibited entry. Modified Lin- dgren 2-funnel traps with a plastic insert to reduce turbulence in the plume and with collecting jars containing water only, caught significantly fewer Douglas-fir tussock moths than traps with empty jars or jars containing soapy water or DDVP insecticide (No-Pest Strip). Traps with jars containing soapy water caught more Douglas-fir tussock moths than traps with jars containing DDVP, but catches were not different from those in traps with empty jars. The catches in traps with empty jars and jars containing DDVP were not significantly different. Non-sticky traps show promise for monitoring the Douglas-fir tussock moth. However, improved designs must facilitate rapid capture of moths landing on the trap, and contamination of exterior surfaces must be minimized. Population trends of the Douglas-fir tussock moth, Orygia pseudotsugata (McDunnough) (DFTM), can be monitored by traps baited with the synthetic sex pheromone, (Z)-6-heneicosen-11-one (Livingston and Daterman 1977, Shepherd and Gray 1984). Sticky traps currently employed for this purpose have two major disadvantages — they saturate at relatively low catch levels and the saturation point varies with the area and amount of adhesive. Sanders (1978) outlined the requirements for a trap suitable for monitoring the eastern spruce budworm, Choristoneura fumiferana (Clem.). The most important characteristics were: sensitivity, i.e. the ability to detect low populations; consistent trapping ability from year-to-year and place-to- place to reflect population trends accurately and comparably; durability; and reasonable cost. Similar requirements are important for other species of moths (Ramaswamy and Cardé 1982, and references therein). Non-sticky traps, which are not subject to satura- tion effects at low levels, have been tested, but the insects often escape from these traps after entering (Struble 1983). To overcome this problem a vaporous insecticide such as dichlorvos, or soapy water has been used (Ramaswamy and Cardé 1982; Snodgrass and Cross 1982; Struble 1983; Lindgren 1983), but the effects of these materials on trap cat- ches need to be evaluated in field experiments. The efficiency of a moth trap depends in part on how the pheromone is dispersed as it leaves the trap 1Present address: Phero Tech Inc., 1140 Clark Drive, Vancouver, B.C., Canada V5L 3K3. (Lewis and Macaulay 1976). Titanium tetrachloride (TiC],), or other smoke of neutral den- sity, can be used in wind tunnel tests to evaluate plume characteristics that may affect insect behavior and catch rates (Angerilli and McLean 1984). The objectives of these investigations were to define the plume characteristics of two versions of a trap not previously tested; to evaluate the effect of various killing agents in a non-sticky trap on catch rates of DFTM in the field; and to compare four models of non-sticky traps with two sticky traps for monitoring the DFTM. MATERIALS AND METHODS Field experiments 1 to 3 were conducted in a severly defoliated Douglas-fir stand alongside the Oregon Jack Creek Road, ca. 15 km south of Ashcroft, British Columbia, in late August and ear- ly September, 1982. Experiments 4 and 5 were con- ducted in a lightly defoliated stand of Douglas-fir alongside the Green Stone Road, Cherry Creek, ca. 18 km west of Kamloops, B.C. in August 1983. In experiment 1, the synthetic pheromone was formulated at 0.1% in PVC rods of 2mmdx5mm long (Daterman 1974). The release rate from these rods is unknown (R. F. Shepherd”, pers. comm.). The formulation is used by the Canadian Forestry Service for minitoring the DFTM in B.C. In ex- periments 2 to 5, the pheromone was released from *Research Scientist, Pacific Forest Research Centre, Victoria, B.C. 4 J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 1 wL capillaries placed in a half dram glass vial with a 3 mm inner diam. orifice, giving a release rate of 10 mg/24 hrs at 25°C. and 30-50% R.H. in the laboratory. Experiments 1 to 3 compared two sticky traps, the Pherocon® 1CP (Zoecon Corp., Palo Alto, California, U.S.A.), and a delta trap made from a two litre milk carton (Daterman et al. 1976), as us- ed by the Canadian Forestry Service (Shepherd 1984), with two non-sticky traps, the Kendall trap (Kendall et al. 1982) and the Lindgren 8-funnel trap (PMG/Stratford Projects Ltd., Vancouver, B.C., Canada). Collecting jars of the non-sticky traps contained 200 mL of water with about 1 mL non-scented detergent/litre of water. The lure in the Lindgren funnel trap was placed in the centre of the trap between the two lowest funnels to optimize pheromone dispersal (Lindgren 1983). Experiments 1 and 2 were each run for about 20 hours on August 23-24 and 24-25, respectively, and experiment 3 was run from August 25 - September 8, to deter- mine saturation effects in the sticky traps (Table 1). Experiment 4 compared dry collecting jars, with and without a 2 x 2 cm piece of a Non-Pest Strip (Shell Chemical Co., 19.2% DDVP? by weight), to collecting jars containing 200 mL of water with or without 1 mL non-scented detergent/litre of water. The trap used in this experiment was a 2-funnel Lindgren trap, modified with a plactic insert (Fig. 1) to improve wind flow over the lure and to pre- vent moths from escaping once inside the trap (Fig. 1B). Each Latin square replicate was run for 2 days, August 20-22 and 22-24, respectively (Table 2). Experiment 5 compared the delta trap with the Lindgren funnel trap (8-funnel, 2-funnel, and the modified 2-funnel used in experiment 4). The two Latin square replicates were run for 2 and 3 days, August 24-26 and 26-29, respectively (Table 3). The smoke plumes from the 2-funnel and the modified 2-funnel traps were defined by wind tun- nel observations of TiCl, smoke (Angerilli and McLean 1984) generated from a wick ina 1.0 cm d x 3.5 cm long shell vial at 25 cm/s wind speed. The vial was placed in the traps in a manner similar to the way in which pheromone containing vials were placed in traps in the field (Fig. 1). Experimental Designs. All field experiments were laid out as 4 x 4 Latin squares to allow for positional effects often encountered in this type of experiment (Perry et al. 1980). Rows and columns were oriented parallel to a road and to prevailing winds, respectively. Replicated Latin squares (Steel and Torrie 1960) were used in experiments 4 and 5 to in- crease the power of error estimation. Data Analysis. All data were transformed as X’ = log 10 (x + 1), to obtain normality of the data and homogeneity of variances, before analyses of variance. Mean separation was evaluated by the Student-Newman-Keul’s Test. 32,2-dichlorovinyl dimethyl phosphate. RESULTS AND DISCUSSIONS Field Experiments In experiment 1, where all traps were baited with the sex pheromone formulated in PVC, the delta sticky trap caught significantly more moths than all other traps (Table 1). When the experiment was repeated with the pheromone released from capillary tubes in vials (experiment 2), the means could not be separated by the Student-Newman- Keul’s Test, althought the treatment effect in the analysis of variance was significant (Table 1). In ex- periment 3, the same traps were tested over a two week period to assess the effect of total saturation in the sticky traps. However, the flight of DFTM males tapered off considerably during this experi- ment, and the estimated saturation levels of 250 and 50 for the delta trap and Pherocon 1CP trap, respec- tively, were not reached. Therefore, the objective of this experiment was not reached. It is noteworthy that although saturation effects in the delta trap are detectable when catches of DFTM ex- ceed 40 moths per trap (Shepherd and Gray 1984), the delta trap compared favorably with the non- sticky traps at considerably higher catch levels. A problem in experiments 1 and 2 was the high variability of some traps, particularly the Lindgren 8-funnel trap. This problem was partly overcome in experiment 3, mainly by consistent trap placement relative to surrounding vegetation, but the variability of the two non-sticky traps remained considerably higher than that of the sticky traps. Similar problems have been noted with non-sticky traps for the western spruce budworm, Choristoneura occidentalis Freeman (Shepherd 1984). The coefficients of variation for the Pherocon 1CP trap were 29.0 and 14.1% in experiments 1 and 3, respectively, but was 84.1% in experiment 2. Similarly, the coefficient of variation was higher (103.6%) for the Lindgren 8-funnel trap in experi- ment 2 than in experiment 1 (72.6%) or experiment 3 (40.0%). The delta trap had consistently low variability in the three experiments with coefficients of variation of 13.5, 16.8 and 10.4%, in ex- periments 1, 2 and 3, respectively. Such consistency must also be achieved with non-sticky traps for them to be useful in monitoring programs for the DFTM, since high variability results in a large number of traps being required to assess the popula- tion trends with reasonable accuracy. Experiment 4 demonstrated that the modified Lindgren 2-funnel traps caught significantly more moths when the collecting jars contained soapy water rather than DDVP or water alone (Table 2). The catches in traps with empty collecting jars were not significantly different from those in traps with soapy water or DDVP. The low catches in traps with only water in the collecting jars could be ex- plained if the moths were repelled by the water. Since there was no significant difference between the catches in traps with an empty jar and those in traps with soapy water and assuming that water alone did repel moths and that soapy water did not, J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 5 Pe ye F Pages tae foe Sate ee ee ov. la Nt’ * we Keitel aie wis "We oo. 6 TOP VIEW SIDE VIEW Fig. 1. Diagrammatic representation of plume formation from a Lindgren 2-funnel trap (A), and from a modified version (B) in which a plastic insert (i) was used to improve air flow over the lure and to decrease the tendency of the plume to curl down and contaminate the exterior of the trap. The pheromone dispenser is in the centre of the trap (d). J. ENTOMOL. Soc. Brit. COLUMBIA 81 (1984), DEc. 31, 1984 "CO°O>d £38aAL S, [Noy-UPUMON—JUIPNAS ‘querlszJTp ATIUeOTJFUSTS You 19azQeT ewes ayy Aq paMOTTOJ suwntoo uzUIIA aa aNs ‘we sks eseatTeal eqn AreT{}deos Tv { f7g6l 6g azaequeydas—cz Tengny- ‘we3sks aeseaTel eqn AreT{}deo Tn] $7g6El 6GZ—Hz sr PeanT pot DAd +7O61 “H2-€2 asnsny CEC—CBT 40°602 TOT-éZ e8°cs 8L-9S %E°L9 deaq AyOFIS eITEG TOC—CET q0°T6l GO?—T 20°66 78-TI q0° CY deiqz Teuunj-g usispuzy CV7—1E 20° 6£ O€-9 bG°el 6 Sys qL£°TZ deiq AYOFIS qOT uodo1rsyd Z8-TE ®0°8S yG-€1 F0°L2 ZI-Z B0°L dei [[Tepuey asuey —YdIeD uPaW ss he’ ueo_ eau a eae ueoW P —€ Jusufzasdxy 4° JUueutiodxy = quoufisedxy deal 2 ‘sorenbs Une] fp X f se und syuauttiadxa “Dg “yyo1oYysy ‘peoy ya01F yor u0Zs19 "SYJOUI YOOssn} Ij-se[snoq Bulddes 103 sdes} Ayors-uou om} pur sdesy AYONS OM} YIM ‘E pu Z ‘T syUauITIedxa jo uoneNyeAy ‘T ATA J. ENTOMOL. SOC. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 TABLE 2. Results of experiment 4, a double 4 x 4 Latin square trial to evaluate the effect of collecting jar content on the catch of Douglas-fir tussock moths in pheromone-baited, modified Lindgren 2-funnel traps. Green Stone Road, Cherry Creek, B.C., August 20-24, 1983. Collecting Jar Content Water DDVP Empty Soapy water a Mean Catch— Range 6.8a 2-1/ 24.0b 4-75 24.1bc 6-48 a “Means followed by the same letter not significantly different, Student-Newman-Keul's Test (p<0.05). the modified Lindgren 2-funnel trap would appear to be virtually escape proof. Although such a feature may be important in a commercial monitor- ing trap, a need for preservation of trapped insects for identification, and for rapid knockdown of possible predators may call for a killing agent to be incorporated into the design. The catches in the four trap types tested ir. experi- ment 5 did not differ significantly (Table 3). The coefficients of variation were similar to those ob- tained in the earlier experiments for the non-sticky traps, but for the delta trap was unusually high (41.9%). This may indicate problems with trap placement, or possibly shifting winds. Fellin and Hengel (1983) placed traps for several species of defoliators on poles between trees, thereby avoiding any effects on the catch by variations in trap place- ment on branches. However, it may be necessary to TABLE 3. Results of experiment 5, a double 4 x 4 Latin square trial comparing a sticky trap and three non- sticky traps for the Douglas-fir tussock moth. Green Stone Road, Cherry Creek, B.C., August 24-29, 1983. Trap Mean Catch— Range Lindgren 2-funnel trap 18.1 4-39 Modified Lindgren 18.9 8-42 2-funnel trap Lindgren 8-funnel trap 23.4 7-34 Delta sticky trap 27.9 14-45 a “No significant differences as determined by analysis of variance (p<0.05). 8 J. ENTOMOL. Soc. BriT. COLUMBIA 81 (1984), DrEc. 31, 1984 place traps for some species near foliage to make them sufficiently sensitive. The western spruce bud- worm responds more readily to traps close to foliage than to traps in the open. (Liebhold and Volney 1984; J. D. Sweeney, unpublished data). Wind Tunnel Observations Wind tunnel observations of TiCl, smoke showed that the “pheromone” plume had a slightly lower tendency to curl back on the downwind side of the modified Lindgren 2-funnel trap in comparison to the unmodified trap (Fig. 1). However, the effect was still pronounced enough to contaminate the outside of the lower funnel and the collecting jar of the modified trap. This self-contamination resulted in moths landing and wing-fanning on the outside of the lower funnel and collecting jar instead of entering the trap. The plumes generated from 2-funnel traps, 8-funnel traps, Kendall traps and Pherocon 1CP traps were all relatively diffuse (Lindgren 1983; Angerilli and McLean 1984), whereas those of the delta sticky traps were linear when the traps were oriented in line with the wind (Angerilli and McLean 1984). Lewis and Macauley (1976) found a positive correlation between plume _ linearity (length/width ratio) and the catch of the pea moth, Cydia nigricana (Steph.), corrected to a standard retentive surface. The Lindgren 8-funnel trap was originally designed for heavy fliers such as bark beetles (Lin- dgren 1983). Its relative success in capturing DFTM (experiments 1, 2, 3 and 5), may have been due to its vertical silhouette which elicited searching behavior by DFTM males, thereby increasing the probability of the moths remaining on the trap until they fell into the collecting jar. Richerson et al. (1976) reported that male gypsy moths, Lymantria dispar L., search vertical silhouettes regardless of the presence or absence of females. Searching behavior of both DFTM and gypsy moth males may be similar, since, the females of both species usually remain on their cocoons after emergence. Many DFTM moths observed at traps in this study, would approach the trap, and then land and search on a nearby tree trunk or branch. Lewis and Macauley (1976) noted that only 25-50% of pea moths approaching a trap were caught. Our field observations indicated that a similar problem existed with the trap-lure combina- tions tested for DFTM. No formal data on the cap- ture rate were recorded, but it was apparent that more than half of the moths observed approaching the non-sticky traps did not enter. Typically, the moths would approach the trap to within 0.5 m, where they would cast back and forth for a limited time before flying away or landing on nearby bran- ches or tree trunks. The omnidirectional non-sticky trap designs tested in our experiments performed relatively well. However, they were generally too variable for use in a standardized monitoring program for the DFTM. Therefore, improvements in the design are necessary. The design must facilitate rapid capture of the moths, and contamination of the outside of the trap must be minimized. The delta sticky trap caught about the same number of moths as the non-sticky designs, but with much less variability making it preferable for monitoring populations. ACKNOWLEDGEMENTS We thank M. Landels and the owners of the Ashcroft Ranch for welcoming research on their respective premises; L. M. Friskie and R. H. Grieve for assistance in the field; Dr. R. F. Shepherd for reviewing the manuscript; and E. Ward for typing the manuscript. This study was supported by funds from the Science Council of British Columbia and the Natural Sciences and Engineering Research Council. REFERENCES Angerilli, N. P. D. and J. A. McLean. 1984. Windtunnel and field observations of western spruce budworm to pheromone-baited traps. J. Entomol. Soc., B.C. 81:10-16. Daterman, G. E. 1974. Synthetic sex pheromone for detection survey of European pine shoot moth. U.S. Dept. Agric., For. Serv. Res. Paper PWN-180, Pac. Northwest For. and Range Exp. Stn., 12 pp. Daterman, G. E., L. J. Peterson, R. G. Robbins, L. L. Sower, G. D. Daves and R. G. Smith. 1976. Laboratory and field bioassay of the Douglas-fir tussock moth pheromone, (Z)-6-heneicosen-11-one. Environ. Entomol. 5:1187-1190. Fellin, D. G. and P. W. Hengel. 1983. Deploying pheromone-baited traps for the western spruce budworm and other defoliating insects. U.S. Dept. Agric., For. Serv. Res. Note INT-330, Intermountain For. and Range Exp. Stn., 7 pp. Kendall, D. M., D. T. Jennings, and M. W. Houseweart. 1982. A large-capacity pheromone trap for spruce budworm moths (Lepidoptera: Tortricidae). Can. Entomol. 114:461-463. Lewis, T. and E. D. M. Macaulay. 1976. Design and evaluation of sex attractant traps for the pea moth, Cydia nigricana Steph., and the effect of plume shape on catches. Ecol. Entomol. 1:175-187. Liebhold, A. M. and W. J. A. Volney. 1984. Effect of foliage proximity on attraction of Choristoneura oc- cidentalis and C. retiniana (Lepidoptera:Tortricidae) to pheromone sources. J. Chem. Ecol. 10:217-227. Lindgren, B. S. 1983. A multiple funnel trap for scolytid beetles (Coleoptera). Can. Entomol. 115:299-302. J. ENTOMOL. Soc. BriT. COLUMBIA 81 (1984), DEc. 31, 1984 9 Livingston, R. L. and G. E. Daterman. 1977. Surveying for Douglas-fir tussock moth with pheromone. Bull. Entomol. Soc. Am. 23:172-173. Perry, J. N., C. Wall, and A. R. Greenway. 1980. Latin square designs in field experiments involving sex attractants. Ecol. Entomol. 5:385-396. Ramaswamy, S. B. and R. T. Carde. Nonsaturating traps and long-life attractant lures for monitoring spruce budworm males. J. Econ. Entomol. 75:126-129. Richerson, J. V., E. A. Brown, and E. A. Cameron. 1976. Pre-mating sexual activity of gypsy moth males in small field plot tests [Lymantria (= Porthetria) dispar (L):Lymantriidae]. Can. Entomol. 108:439-448. Sanders, C. J. 1978. Evaluation of sex attractant traps for monitoring spruce budworm populations (Lepidoptera: Tortricidae). Can. Entomol. 110:43-50. Shepherd, R. F. 1984. Comparison of pheromone trap designs to catch spruce budworm moths. Proc. IUFRO Conference, Banff, Alberta (in press). Shepherd, R. F. and T. G. Gray. 1984. Pest management of Douglas-fir tussock moth: monitoring endemic populations with pheromone traps to detect incipient outbreaks. Can. Entomol. 116: (in press). Snodgrass, G. L. and W. H. Cross. 1983. The use of DDVP in Leggett trap tops to improve trap efficiency. J. Georgia Ent. Soc. 18:50-53. Steel, R. G. D., and J. H. Torrie. 1969. Principles and Procedures of Statistics. McGraw-Hill Book Com- pany, Inc., New York, 481 pp. Struble, D. L. 1983. Pheromone traps for monitoring moth (Lepidoptera) abundances: Evaluation of cone orifice and omni-directional designs. Can. Entomol. 115:59-65. ime SCIENTIFIC WRITING B FOR y—2e GRADUATE STUDENTS This manual is a “must” for those who would introduce courses of in- struction in scientific writing into university graduate schools. The first nine chapters provide the essentials for “Writing a Journal Article,” and the remaining five chapters cover “Related Topics” in scientific com- munication. CONTENTS: |. Clearing Away the Underbrush ¢ 2. The Ground Plan e 3. The Master Plan @ 4. The First Draft ¢ 5. The First Revision: Structural Alterations ¢ 6. Further Revision: Polishing the Style ¢ 7. Editing Assignments ¢ 8. The Final Steps ¢ 9. Re- sponding to the Editor ¢ 10. Design of Tables and Figures ¢ 11. Prep- aration for Writing the Doctoral Thesis ¢ 12. Writing a Research Pro- ject Proposal e¢ 13. Oral Presentation of a Scientific Paper e 14. Principles and Practices in Searching the Scientific Literature Paperbound; ISBN: 0-914340-01-8; Published 1968, reprinted 1983; Trim size: 6 x 9 inches; 190 pages Regular Price: $9.75 (10% discount on 10 or more copies delivered to one address) CBE Member Discount Price: $8.75 (single copy paid by personal check) Terms of Sale: All sales final; no returns. Prepayment required; U.S. currency drawn on a U.S. bank. Price includes BOOK RATE postage. For faster delivery--first class, air mail, or UPS available at additional charge (book weight, 11.5 oz). Maryland residents, please add 5% sales tax. COUNCIL OF BIOLOGY EDITORS, INC. 9650 Rockville Pike, Bethesda, MD 20814 10 J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 WINDTUNNEL AND FIELD OBSERVATIONS OF WESTERN SPRUCE BUDWORM! RESPONSES TO PHEROMONE-BAITED TRAPS? N. ANGERILLI? AND J. A. MCLEAN Faculty of Forestry University of British Columbia Vancouver, B.C. V6T 1W5 ABSTRACT Five trap designs, the Pherocon 1CP, a triangular trap, dome trap, double cone trap and Kendall trap were evaluated for capturing the western spruce bud- worm, Choristoneura occidentalis Freeman, both in a laboratory-based windtun- nel and in an infested stand. Neutral density smoke tests showed the effects of orien- tation to wind on plume formation as well as highlighting plume structure around larger traps. Moth capture rates in the windtunnel did not always correlate with capture rates under field conditions. INTRODUCTION Pheromone-baited traps have proven useful for monitoring many species of insects and are often in- tegral parts of pest management programmes (Ken- nedy 1981). Such traps are most useful if they are consistent in their catches and reflect the relative abundance of the insect being monitored. Several designs of sticky traps have been evaluated against the spruce budworm, Choristoneura fumiferana (Clem.), (Sanders 1978; Houseweart et al. 1981). Omnidirectional high capacity traps have also been tested for moths (Steck and Bailey 1978; Struble 1983) with several designs recently developed and tested specifically against the spruce budworm (Ramaswamy and Carde 1982; Kendal et al. 1982). One difficulty with testing traps in the field is determining how many insects were attracted but not captured. That is, it is difficult to know how “efficient” a given trap design is except relative to other traps. The objective of this study were to observe and measure the absolute efficiency of several trap designs to attract and capture male western spruce budworm (WSBW) C. occidentalis Freeman, under laboratory conditions in a windtunnel; to relate this efficiency to the size and shape of emitted pheromone plumes; to make predictions, based on these results, of the field efficiency of the tested traps; and to test the laboratory predictions in the field. MATERIALS AND METHODS A 4.88 m long windtunnel with 1.2 m square cross section was built and calibrated for wind speeds from 0 to 1.4 ms-'. The front side and top of the tunnel were of clear acrylic plastic while the back and bottom were fir plywood. Air was drawn through a smooth curve entrance and double screens in order to produce a laminar windflow. Measurements of wind speed demonstrated uniform + Choristoneura occidentalis; Lepidoptera: Tortricidae. *Present address: Agriculture Canada, Research Station, Sum- merland, British Columbia VOH 1Z0. 3Contribution No. 605, Research Station, Summerland. cross tunnel velocities and the presence of a 2.5 cm still air boundary layer which helped to minimize pheromone contamination of the windtunnel. The end of the tunnel was also screened to prevent escape of insects. Quarter sections of the acrylic panels were hinged at the front and rear of the tun- nel to facilitate access for test materials and insects. Air was drawn from the tunnel and expelled to the outside of the building. All tests were conducted at 0.5 ms) The traps tested in the tunnel were the Pherocon 1CP (Zoecon Corp.), a triangular trap (Cory et al. 1982), a double cone trap, a dome trap and the Kendall trap (Fig. 1). The first two traps rely on sticky inner surfaces to trap attracted insects while the last three were no-exit type non-sticky traps. In order to visualize the pheromone plume emitted from these traps, an approximation was made by using titanium tetrachloride neutral density “smoke”. The TiCl, was released from half-filled one dram glass vials with a 2 cm long string wick to act as an evaporative surface. The vial of TiCl, was positioned inside each trap at the same point as the pheromone dispenser. Each trap was tested to determine the smoke plume (and so to infer the pheromone plume) from the trap in line with the wind (180°), crosswind (90°) and at an angle to the wind (45°). The plumes were recorded on pan- chromatic film and later sketched. Western spruce budworm from the non- diapausing strain kept at the Pacific Southwest Forest Range Experiment Station at Berkeley, CA, were reared on artificial diet (BioServ® 9769). Pupae were placed into individual containers and kept in a light dark regime of 16 and 8 h with dawn occurring at 2400 h and dusk at 1700 h. Adults were kept under the same regime until three days old when they were used once between 1300 h and 1800 h in flight tests. After testing, the moths were kept for a further 24 h. The data were retained only from those insects that survived. The synthetic WSBW pheromone, a 92:8 blend of (E) and (Z)-11-tetradecenal (E, Z11-14:A1), was dispensed from 10 wL glass capillaries contained in J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), Dec. 31, 1984 11 Fig. 1. Traps evaluated in the UBC windtunnel using TiC], neutral density smoke; traps A-D also tested for efficiency in capturing WSBW when baited with pheromone; all traps tested in the field, A. Pherocon 1CP trap, B. Triangular trap, C. Dome trap, D. Double cone trap, E. Kendall trap. an open 1 dr. glass vial. The pheromone test pro- cedure consisted of taking the males out of the con- trolled environment rearing chambers 0.5 h before the beginning of testing and the pheromone-loaded capillaries out of refrigeration 1 h before testing. The pheromone-baited trap was placed in the tun- nel entrance as described for the trap smoke tests. Males were released individually at the opposite end of the tunnel onto a circular glass platform (diameter = 20 cm) so positioned that the moth was in the estimated centre of the pheromone plume. Time-to-flight initiation (latency), time-in-flight, and time-to-capture (where appropriate) after reaching the pheromone source, were recorded in seconds. Males were also scored as being responders or non-responders. Typically, a responder faced in- to the wind with the longitudinal body axis in line with the wind direction, exhibited pre-flight wing- fanning, and took-off into the wind; the resulting flight line was a zig-zag upwind in the estimated plume region towards the pheromone source on which it landed and exhibited post-flight or pre- mating walking and wing-fanning. A _ non- responder usually failed to fly although it sometimes faced into the wind or took off downwind. Traps were tested using three capilaries of E,Z11-14:Al as this was shown to produce 80% responders, a short latency (x = 5.75s,n = 10), and a fast flight time (x = 33.9s, n = 10). The three directional traps were tested at the three trap- to-wind angles previously mentioned. The com- parative test of the Pherocon 1CP, triangular (apex down), dome, and double cone traps was run as a 4 x 4 latin square in which each trap was tested daily for 4-days using five individually released moths per trap. The test was re-randomized and run a second time. To test windtunnel predictions of the relative effi- ciencies of the previously tested traps, a 6 x 6 latin square design experiment was established near 12 J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), Dec. 31, 1984 Cc Fig. 2. TiCl, smoke plumes from two sticky traps: Triangular trap showing A. side view at 180° to wind, B. top view at 90° to wind, and C top view at 45° to wind; and Pherocon 1CP trap showing D, top view in line with wind, E. side view in line with wind and F. top view at 45° to wind. Oregon Jack Creek, B.C. in an area of moderate to high WSBW infestation. The fifth and sixth traps were the triangular trap with the apex up rather than down and the Kendall trap (Kendall et al. 1982). The experiment was initiated on the evening of 16 August 1982 and moths were counted and the traps emptied at mid-day on 17 and 18 August 1982. J. ENTOMOL. Soc. BriT. COLUMBIA 81 (1984), DEc. 31, 1984 13 RESULTS AND DISCUSSION The triangular trap produced a relatively dense and stable plume when orientated in line with the wind (Fig. 2A). The trap was always tunnel-tested apex down, however, and after two or three males had struggled in the sticky coating at the trap’s en- trance it became less sticky due to wing scales coating the sticky surface. Later, males were sometimes seen to enter the trap, continue wing fanning and eventually reemerge from the trap and fly away. When oriented across wind, some smoke was still released (Fig. 2B), and at 45° to the wind a broader, less dense plume was produced (Fig. 2C). When the Pherocon 1CP trap was in line with the wind it produced a broad (Fig. 2D), dense (Fig. 2E) and easily, tracked plume. The side view (Fig. 2E) shows that there was some “backwash” of the plume and males were often observed walking and fanning in this area prior to entering the trap. A less dense plume was produced when the trap was at 45° to the wind (Fig. 2F). When set out at 90° to the wind, no visible smoke plume was produced. The dome trap produced a narrow plume but had the advantage of producing it directly from its opening (Fig. 3A), and responding males normally did not find it difficult to find and enter the trap. The novel design of the trap was based on air pressure differences between its bottom and top caused by the longer travel path of air flowing over the top relative to air flowing under the bottom. The pressure difference caused air to flow through holes in the bottom of the trap which was equipped with one-way flap valves into the traps’ interior where it became pheromone laden and then emerg- Fig. 3. TiCl, smoke plumes from A. Dome traps, B. Double cone trap, C. Kendall trap (top view), and D. Kendall trap (side view). 14 J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 TABLE 1. Comparison of male WSBW responses to pheromone baited traps oriented at 180°, 45° and 90° to the windflow in a windtunnel (n = 10). Trap Orientation Latency Time in Time to Number design windflow (°) time(s) flight (s) capture(s) captured Triangular 130 Dad a 24.0 a yo eo ae 8 45 3ek 4 17.5 a 33.44..a 9 90 2.9 a IS. @ 48.12 a 8 Pherocon 1CP 730 Lo a 14.9 a 21.8 2 10 45 22404 2406/22 93.0) Db 8 90 Za Dca 27..5--a 128. b yi Double cone 130 De La 58.94 84.3 a 6 45 ge ar | 20.5.4 86.6 a 5 90 10 Eva 18.9 a 139.6 a 5 uE Means followed by the same letter within columns and within trap types are not significantly different (Student Newman-Keuls, P < 0.05). TABLE 2. Mean number of male WSBW caught by four trap designs oriented in line with the wind in a wind tunnel experiment (n = 5 per replicate, 4 replicates run in a latin square randomization con- figuration). The experiment was run twice. Mean catch? Trap Run 1 Run 2 Combined Pherocon 1CP A575 a de 25) 2) 4.50 a Triangular (apex down) 3.00 ab 2 50) .2 3200 b Dome 3.50 ab 502554 32.300-aD Double cone 2.00 b 2s J D2 2304 Iveans followed by different letters are significantly different (Student Newman-Keuls, P < 0.05). J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 15 TABLE 3. Mean number of male WSBW caught by six traps of five designs during two nights in 1982 near Oregon Jack Lake, B.C. Mean catch + s.d.t Trap July 16/17 July 17/18 Pherocon 1CP 26,09 = iL.7 a Woes +) 2a Triangular (apex up) 1593) 2 LOROUb 3907 ows Triangular (apex down) 13¢o 2 4.4 b 26s. 2 Sea pb Kendall 6 1 Oia ee ee alee beo.3 = 48.8 be Double cone 2D ee 355 2° 1.45 ¢ Dome 02302 (0.5 0¢ 0. = 0 < Total moths captured 366 7T8Z eee transformed to xt = log (X+1) prior to analysis of variance. Means not followed by the same letter are significantly different (Student Newman-Keuls test, P < 0.05). Two of the six traps became inoperative during the first night, but were repaired for the second. ed through a single hole in the top of the trap. The tested. Results for the Pherocon 1CP trap in line double cone trap produced a much broader plume with the wind were the best obtained, with the with much back-flow over the outside of the trap _— smallest latency time, least time in flight, fastest (Fig. 3B) up to the central connecting ring. This _ time-to-capture, and all the male WSBW captured. backflow could result in considerable contamina- This trap was sensitive to cross-wind orientations tion of the outside of the trap. When male WSBW _ with less dense plume formation (Fig. 2F) which landed in this area they would walk and continue to __ resulted in extended periods to capture (Table 1). wing-fan for an extended period and occasionally The plume from the double cone trap was con- enter the trap if they encountered the entrance. The _ siderably enlarged when the trap was oriented in Kendall trap generated a broad plume (Fig. 3C) _ line with the wind. The diffuseness of the plume by which also may have contaminated the outside of the time it crossed the take-off platform might ac- the collecting jar (Fig. 3D). Certainly many males _count for the increased latency times (Table 1). The fanned extensively over the outside of the collecting _ long time-to-capture probably reflected the difficul- jar without locating the entrances to the trap. ty of the male WSBW in locating the entrance hole Moths also readily walked out of this trap rather in the perforated end screen in the trap (Fig. 1d). than dropping into the collecting jar. In the first series of pheromone experiments in the windtunnel (Table 1) it was seen that the triangular trap captured more than 80% of the test insects and had low latency periods which confirmed the ade- quate plume formation seen in the tunnel. These results were consistent for all trap orientations The Pherocon 1CP was consistently the most ef- fective trap in the windtunnel (Table 2). The results suggested that the dome trap was a promising design and that the double cone trap was consistent- ly inefficient. In the field experiment, the Pherocon 1CP trap consistently captured the most male 16 J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 WSBW (Table 3) more than double the numbers caught in the best high capacity trap. The one night tests did not really test the high capacity trap func- tion although it is clear that none of the high capaci- ty designs were as effective as the sticky traps. The triangular trap captured more moths when the apex of the trap was uppermost (Table 3). This suggested that the larger landing platform may have provided an important additional entrapment area. The greatest disappointment, was the poor showing of the dome trap. Smoke tests showed that wind pat- terns within the stands where trapping was carried out were variable and of a much lower velocity than the 0.5 m s“ windspeed used in the windtunnel to calibrate and test the trap. The results of this study have shown that smoke testing of traps in a windtunnel can provide valuable information on the integrity of plume for- mation and shape in relation to orientation to the wind. Pheromone-baited traps can be evaluated as to their efficiency but these results will not necessarily be reflected by catches in the same traps under field conditions. The currently used triangular trap appears to be as effective as any other design at low population levels before the trapped moths saturate the traps. REFERENCES Cory, H. T., G. E. Daterman, G. D. Daves, Jr., L. L. Sower, R. F. Shepherd and C. J. Sanders, 1982. Chemistry and field evaluation of the sex pheromone of western spruce budworm, Choristoneura oc- cidentalis, Freeman. J. Chem. Ecol. 8:339-350. Houseweart, M. W., D. T. Jennings and C. J. Sanders. 1981. Variables associated with pheromone traps for monitoring spruce budworm populations (Lepidoptera: Tortricidae). Can. Ent. 113:527-537. Kendall, D. M., D. T. Jennings and M. W. Houseweart. 1982. A large-capacity pheromone trap for spruce budworm moths (Lepidoptera: Tortricidae). Can. Ent. 114:461-463. Kennedy, J. W. 1981. Practical application of pheromones in regulatory pest management programs. In Mitchell, E. R. (ed) Management of Insect Pests with Semiochemicals — Concepts and Practice. Plenum Press N.Y. pp. 1-12. Ramaswamy, S. B. and R. T. Carde. 1982. Nonsaturating traps and long-life attractant lures for monitor- ing spruce budworm males. J. Econ. Entomol. 75:126-129. Sanders, C. J. 1978. Evaluation of sex attractant traps for monitoring spruce budworm populations (Lepidoptera: Tortricidae). Can. Ent. 110:43-50. Steck, W. and B. K. Bailey. 1978. Pheromone traps for moths: evaluation of cone trap designs and design parameters. Environ. Entomol. 7:449-455. Struble, D. L. 1983. Pheromone traps for monitoring moth (Lepidoptera) abundances: evaluation of cone- orifice and omni-directional designs. Can. Ent. 115:59-65. J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 17 THE EFFECT OF HEIGHT OF PHEROMONE-BAITED TRAPS ON CATCHES OF THE AMBROSIA BEETLE, TRYPODENDRON LINEATUM T. L. SHORE Agriculture Canada Pacific Forest Research Centre 506 West Burnside Road Victoria, B.C. V8Z 1M5 J. A. MCLEAN University of British Columbia Faculty of Forestry 2075 Wesbrook Mall Vancouver, B.C. V6T 1W5 ABSTRACT Pheromone-baited sticky traps were suspended at five heights in five locations to determine the optimum height for catching the ambrosia beetle Trypodendron lineatum (Oliv.). Maximum catches were obtained on traps at, or just below, the height of the surrounding underbrush. RESUME Des piéges a phéromones utilisés pour le dénombrement des populations ont été accrochés a cinqu hauteurs, en cing endroits, pour déterminer la hauteur op- timale de capture du scolyte birayé (Trypodendron lineatum [Oliv.]). Le nombre maximal de captures a été obtenu 4 la hauteur du sous-bois environnant ou juste au- dessous. INTRODUCTION Ambrosia beetles cause losses to the forest in- dustry by boring “pinholes” into logs and green timber. Pheromone-baited traps have been used in recent years for surveying and mass-trapping am- brosia beetles in timber sorting and processing areas (Borden and McLean 1981, Lindgren and Borden 1983, Shore and McLean, in press). In order to im- prove future trapping efforts, an experiment was established to identify the effect of trap height on catches of T. lineatum. METHODS AND MATERIALS Twenty-five survey traps, each consisting of 0.64 cm wire mesh formed into a cylinder 20 cm in diameter and 46 cm in length attached at the top to a plywood disk, were coated with Stikem Special® (Michel and Pelton Ltd., Emeryville, Calif.). On 21 May 1980 five traps were suspended from a rope in each of five locations. In each group of five, the bot- tom of the traps were at 0.0, 1.0, 2.0, 3.0 and 4.0 m above the ground. Each trap was baited with two Conrel® fibres (Albany International Co., Needham, Mass.) containing lineatin, the aggrega- tion pheromone of T. lineatum (MacConnell et al. 1977; Borden et al. 1980) giving a combined release rate of approximately 20 micro grams per day. The average height of understory vegetation surroun- ding the traps was measured. Beetles were removed from the traps on several occasions, identified as to sex and counted. The experiment was concluded on 5 August (76 days). The total number of beetles of each sex caught on each trap was determined. In order to remove differences due to locations and sexes the numbers at each of the five trap heights were converted to the proportion of total beetles of each sex caught at each location. All subsequent analysis was done on this variable. RESULTS AND DISCUSSION A total of 5,493 beetles was trapped. The ratio of male to female T. lineatum was 1.24:1.00; the stronger response to the pheromone by the male reflects the fact that the female is the first-attacking and pheromone-producing sex in this species. In order to determine if the response to trap height was consistent between the sexes the proportion of each sex (as determined above) caught on each trap was tested using a t-test for paired comparisons. No significant difference was found between the sexes (P>0.05); therefore, they were combined in subse- quent analyses. The percentage of the total number of beetles caught at each location by trap height is shown in Table 1. Analysis of variance of this variable show- ed there were significant differences between trap heights at the .05 probability level. A multiple com- parison test showed significant differences between the highest trap height (4.0-4.5m) at which the fewest of beetles were caught and the second lowest trap height (1.0-1.5m) where the most beetles were caught (Table 1). Considerable differences between locations in the distribution of beetles by trap height were evident. While traps in the 1.0-1.5m height 18 J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 TABLE 1. Percentage of total number of Trypodendron lineatum caught in each location at each of five trap heights. Location Trap Height (wm) i 2 3 th eeand 0.0 - 0.5 19.2 6.9 39.4 9.6 14.7 18.0 ab 1.0 - 1.5 55.9 47.0 30.8 12.4 ~31a7 31.6 a 2.0 - 2.5 2540 2200 16.1 21.0 43.0 ~25.6 ab 3.0 - 3.5 12.6 13 Gal 30.8 8.8 14.5 ab 4.0 - 4.5 0.7 i223 4.6 2052 1.8 fOeoeb Total number caught 1264 408 864 1844 11h3 Avg. height of underbrush (m) ee LZ 1 4.0 330 a i nn a a re et ‘Means followed by the same letter are not significantly different. Student-Newman-Keuls test, P<0.05. class ranked first or second in percentage of beetles caught in four locations, location 4 showed a dif- ferent distribution entirely. Examination of the average height of surrounding underbrush provided a possible explanation for these location differences. In locations 1, 2 and 3, where the underbrush was 1.5m or less in height, traps in and below this height class caught the highest percentage of beetles. Loca- tions 4 and 5 had much higher understory vegeta- tion surrounding the traps, and in both cases traps in the height class just below the top of the under- brush caught the most beetles. These results suggest that T. lineatum responds optimally to pheromone- baited traps placed at, or just below, the height of the surrounding vegetation. REFERENCES Borden, J. H., A. C. Oehlschlager, K. N. Slessor, L. Chong and H. D. Pierce Jr. 1980. Field tests of isomers of lineatin, the aggregation pheromone of Trypodendron lineatum (Coleoptera: Scolytidae). Can. Ent. 112:107-109 Borden, J. H. and J. A. McLean, 1981. Pheromone-based suppression of ambrosia beetles in industrial timber processing areas. In E. R. Mitchell (Ed.). Management of insest pests with semiochemicals: Concepts and practice. Plenum Press, New York. pp. 133-154. Lindgren, B. S. and J. H. Borden, 1983. Survey and mass trapping of ambrosia beetles (Coleoptera: Scolytidae) in timber processing areas on Vancouver Island. Can. J. For. Res. 13:481-493. MacConnell, J. G., J. H. Borden, R. M. Silverstein and E. Stokkink. 1977. Isolation and tentative iden- tification of lineatin, a pheromone from the frass of Trypodendron lineatum (Coleoptera: Scolytidae). J. Chem. Ecol. 3:549-561. Shore, T. L. and J. A. McLean. In press. A survey for the ambrosia beetles Trypodendron lineatum (Oliv.) and Gnathotrichus retusus (LeC.) (Coleoptera: Scolytidae) in a sawmill using pheromone-baited traps. Can. Ent. J. ENTOMOL. SOc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 19 COLOR VIDEO TAPE TO RECORD FOREST DEFOLIATION R. I. ALFARO and T. L. SHORE Canadian Forestry Service Pacific Forest Research Centre 506 West Burnside Road Victoria, B.C. V8Z 1M5 Aerial surveys of forest insect damage conducted by the Forest Insect and Disease Survey in British Columbia utilize in-flight recording of the visual observations of trained observers directly onto field maps (sketch mapping) (Harris and Dawson 1979). Final maps are prepared in the office and com- plemented with additional information collected on the ground or by oblique color photography obtain- ed during flight (Harris 1971). Recent developments in video technology have made the use of video camera recording equipment for aerial forest insect surveys economically feasible. This note reports on the advantages and disadvan- tages of using video cameras for complementing aerial sketch information as observed furing a field test in 1983. In July 1983, color video coverage was obtained of Douglas-fir, Pseudotsuga menziesii (Mirb.) Fran- co, stands defoliated by Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough), in the Kamloops area of British Columbia. The video was recorded using a Hitachi portable video recorder from a low-flying fixed-wing aircraft. Several advantages of video tape coverage over conventional oblique aerial photography or sketch mapping alone became apparent. The large tape capacity allowed continuous running of the unit and hence the storage of large amounts of sequential images. This resulted in much greater coverage of damaged stands. The video tape could be reviewed in the plane through the camera’s monitor to see if the desired coverage has been obtained. Also, the observer’s comments could be recorded along with the video image. The tape could be viewed im- mediately after the flight and adjustments made to the sketch maps based on the visual record of geographic and pest damage information. The sweeping panoramas allowed the viewer to “get his bearings” which is difficult with individual still photographs. Also the film acts as a permanent record or can be reused. For demonstration pur- poses, the video tape system was useful; it provided a simulation of flight as the observers saw it, and could be edited to any desired length, omitting un- necessary detail. Zoom capability can be a positive factor, but at the higher zoom settings it was dif- ficult to hold the camera steady enough to obtain good picture quality. There are limitations to the video tape system. Equipment was bulky and complicated to handle in flight, although more compact units are now becoming available. The resolution was lower than that in aerial photographs, so edge distinctions bet- ween damaged and healthy stands were less defined and individual trees were harder to pick out. The angle of the sun was more critical to the resultant video image than for airphotos. Optimum image quality was produced when the operator had the sun behind him and was shooting down at roughly 45° - 90°, and relatively close to the area being recorded (300 - 1000 m). If the viewing angle allow- ed any of the horizon to show, an overall blue cast predominated in the imagery, which eliminated the visual distinction between healthy and damaged stands. When the sun and the viewing angle were cor- rect, damaged stands were fairly distinctive, especially those stands with a large component of dead (grey) and more intensely defoliated (reddish) trees. Smaller and lighter areas of damage were harder to delineate, especially when the viewing angle was not ideal (poor sun angle) or the target area was too distant. We concluded that video recording could be a valuable complementary tool to sketch mapping of defoliation if used correctly. ACKNOWLEDGEMENT We wish to thank A. F. Dawson and R. D. Erickson for technical assistance. REFERENCES Harris, J. W. E. 1971. Aerial photography (35 mm): Aid to forest pest surveys. Can. For. Serv. Bi-monthly Res. Notes 27:30. Harris, J. W. E. and A. F. Dawson. 1979. Evaluation of aerial forest pest damage survey techniques in B.C. Can. For. Serv. Pac. For. Res. Cent. Inf. Rep. BC-X-198, 22 p. 20 J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 OBSERVATIONS ON THE BIOLOGY OF PRIONUS CALIFORNICUS MOTS. ON HOPS, HUMULUS LUPULUS L, IN IDAHO! Guy W. BISHOP, JACQUELYN L. BLACKMER AND CRAIG R. BAIRD Southwest Idaho Research and Extension Center University of Idaho, Parma, Idaho 83660 ABSTRACT The damage potential, seasonal flight activity and larval development of Prionus californicus were investigated over five years in Idaho hop yards. Hop plants were not susceptible to oviposition and larval establishment until after their second year. Crowns of severely infested plants were reduced to masses of frass and rotted areas. Major roots were frequently tunneled and girdled. First foliar symp- toms were loss of vigor and often one or more wilted and yellowing shoots. Some af- fected plants died within a few months while others became less vigorous over several years. Two kinds of damage occurred: the first was from larvae that developed within root systems in established yards; the second was root damage to new plantings from larvae left in the soil when the old yard was taken out and replanted to hops. Beetle flight occurred only during July with day-to-day variation at least partially related to minimum temperatures and to precipitation. Young lar- vae were found almost entirely in the vascular region of roots to a soil depth of about 200 mm. Older larvae were in both living and dead roots to a soil depth of about 500 mm. Based upon measurements of 243 larvae taken from 50 hop root systems, the life cycle of the species is usually 4 years. INTRODUCTION Prionus californicus Mots. is widely distributed in the Pacific slope of the United States and British Columbia (Doane et al., 1936). Oak is the most common and apparently preferred host, but the species has been recorded from the roots of a variety of other broadleaved plants including poplar, alder, apricot, eucalyptus and grape, and from roots and stumps of several pines (Pinus spp.), Douglas fir (Pseudotsuga menziesii), Sequoia, Abies and butts of red-cedar (Thuja sp.) poles (Doane et al., 1936; Keen, 1952). Essig (1926) reported that the larvae can feed on living roots and frequently kill fruit trees as well as native hosts. In New Mexico, Eyer (1942) found apple trees to be preferred over several other orchard fruits. Hop growers in Idaho have noticed damage from P. californicus since at least the 1930’s and their observations indicate that the longevity of a severely infested yard may be reduced by one half. The pro- blem is compounded by the practices of concen- trating production in certain favourable areas and planting new hops in old yards without several years rotation of other crops. Hop production in Idaho is centered in an area about 150 km? in the southwest part of the state, in 3 relatively distinct areas near the communities of Wilder, Greenleaf and Notus. The principal varieties are Talisman, Late Clusters and Galena. Crawford and Eyer (1928) and Eyer (1942) ‘Idaho Agricultural Experiment Station Research Paper 83715. studied the biology and control of P. californicus on apples in New Mexico. Little information is available on other crops and apparently there have been no studies on hops. The objectives of the pre- sent study were: 1. to assess damage potential of the species; 2. to obtain information on seasonal flight activity; and 3. on larval development; and 4. to assess control possibilities. MATERIALS AND METHODS General observations on larval development and damage were made from 1977 to 1982 by digging around individual plants to expose crowns and up- per roots. Exposed parts were washed with water from a pressurized sprayer. When soil was replaced soon after examination the procedure had little ef- fect on plant growth but was clumsy and time con- suming. Detailed observations on size and location of larvae in root systems required sacrificing the plants in order to thoroughly clean and dissect crowns and roots. To monitor flight periods of the beetles light traps were placed in 7 to 9 hop yards in each of 3 seasons. Traps were slightly modified from the Ellisco General Purpose “Black Light” Trap (Ellisco Inc., Philadelphia, PA). Traps were put out well in ad- vance of anticipated emergence and maintained un- til no beetles were caught for at least 2 weeks. Traps were serviced every 2 to 3 days in 1980 and daily in 1981 and 1982. Weather records reported in rela- tion to the number of beetles trapped were from the Southwest Idaho Research and Extension Center, Parma. The weather station was within 12 km and J. ENTOMOL. Soc. Brit. CoLuMBIA 81 (1984), DEc. 31, 1984 21 250 m elevation of all light trap sites. Each of the 3 periods of measurable precipitation was from general weather systems that affected the entire area. Data on measurements of larval length were analyzed using the EM algorithm for normal populations as outlined by Everitt and Hand (1981). RESULTS AND DISCUSSION Damage Two distinct kinds of damage were observed. The first was in yards older than about 7 years and was caused by long-term infestations which weakened and eventually killed plants. In severely infested plants, crowns were reduced to masses of frass and rotted areas, and major roots were frequently tun- neled and girdled. Up to 20 larvae were found in single root systems. Early foliage symptoms were a lack of vigor, often with one or more wilted and yellowing shoots. Some plants observed to be af- fected in early summer died later in the season or the following spring. Others simply lost vigor over a period of years. Observations in several severely in- fected yards showed all plants to have some degree of damage. Although individual plants were sometimes replaced, growers typically removed en- tire yards when infestations became sufficiently ex- tensive to seriously depress yields. Observations on several new plantings showed that plants were not infested in the first or second year. This apparent immunity could result because crown areas of young plants are too smooth to be at- tractive for oviposition. Doane et al. (1936) reported that eggs are deposited in crevices near the soil level. It is also possible that larvae cannot become established because of the intense vigor of young plants. Eyer (1942) found that vigorously growing young apple trees were not frequently infested. The second type of damage occurred when old yard sites were replanted to hops. New plants are usually placed in the same locations as those previously removed to avoid changing the location of trellises. Roots and crowns, therefore, are subject to damage from P. californicus larvae left in the soil. Young plants were sometimes completely cut off and died before the end of the first season. In yards examined the second and third year after planting, up to 20% of the root systems were damaged. Potential for damage remains even if another crop is in rotation for one year between hop plantings. In one case where the interim crop was potatoes, several larvae were found feeding on the tubers, one on a cedar stake, and others on pieces of hop roots left in the soil. Flight period and Activity of Adults Light trap catches during 3 years showed the flight period of P. californicus to be essentially restricted to the month of July (Fig. 1). Day-to-day variation in numbers caught during 1981] and 1982 was generally related to warm night temperatures as indicated by daily minimum temperatures (Fig. 1). The only other factor identified was precipita- tion which apparently had an influence exclusive of temperature during the July 4-8 period, 1981 and on July 28, 1982. Peak numbers were trapped about halfway through the annual flight period each year. This was evidently after most beetles had emerged but little mortality had occurred. Annual numbers of beetles per trap site varied from 0 to 174 over the 3 years. No beetles were caught in traps in the Greenleaf area but beetles were caught in every trap in the Wilder and Notus areas each year. During daylight hours beetles were found in the duff at the base of hop plants where dense growth may provide required shade and protection. Beetles confined to plant bases in cages lived for about 10 days. A series of dissected gravid beetles contained from 150 to 210 eggs. Eggs were not found in the field where they are difficult to detect since they are sticky and become covered with fine soil particles. Eyer (1942), however, found eggs were deposited from about 12 to 37 mm below the soil surface near the bases of apple trees in cage experiments. Larval Development P. californicus larvae were removed from 50 root systems collected in April, 1982, from an 8-year-old moderately infested hop yard. Size distribution of the 243 larvae recovered (Fig. 1) suggested that they represented 4 groups. The first two with boundaries of 3 to 10 mm and 14-21 mm respectively appeared distinct, whereas the third with boundaries of 23 to 35 mm and the fourth made up of larvae larger than 35 mm, were less distinct. To test the hypothesis that these size distributions represented 4 popula- tions we used the EM algorithm for normal popula- tions (Everitt and Hand, 1981). For each of the four populations initial values of the proportion of that particular population to all populations, pj, the variance, of, and the mean, yj, were estimated. Assuming normal distributions, probabilities for each of the individual 243 observa- tions coming from each of the four hypothesized populations were computed, and new estimates of pj|, of, and pjwere chosen by the algorithm to max- imize the probabilities of belonging to the specified groups. This process was iterated until a reasonable convergence was achieved. Equations for the curves depicting the 4 hypothetical normal populations (Fig. 2) were based on the sixth and final iteration. The appropriate Z or t values were next calculated for each of the four populations with population boundaries set at 12.5, 21.5, and 37.5 mm respectively. Then the expected number of lar- vae in each of these intervals from each of the four populations was computed. For example for the first population (.607) (243) = 148 expected from the EM algorithm. The gains and losses from the hypothesized populations along with their observed values are shown in Table 1. A simple chi-square calculation with three degrees of freedom, yields a calculated x? J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 22 & 2 § é = : $ o—— Beetles DAILY MINIMA (0°) oo rFneioewdvseFPFNnN oe oo FN oOo HOH TN SO $311338 WLOL 26 30 4 8 12 16 20 24 28 1 5 9 13 August July June DAILY MINIMA (0°) NnoOowMwo tno 5 9 August 22 26 30 4 8 12 16 20 24 28 1 oo rTFnriaoesewvsoetn o $311338 1WLOL July June 1980 14 12 i=) i°) o $311338 IWLOL zt 28 2 6 10 14 18 22 26 30 3 7 9 11 August July June Fig. 1. Relationship between temperature (daily minima) and precipitation (p) and light trap catches of Prionus californicus in Idaho hop yards. J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 23 = .15, (p = .98) which is much less than 9.49 which would be needed to reject the null hypothesis at the .05 level of significance. The close correspondence of the hypothesized 4 populations to observed size groups (Fig. 2) ap- parently supports the contention of Eyer (1942) that the species usually matures in the fourth year. It seems probable that larvae represented by the distinctive populations 1 and 2 were essentially 1 and 2 years old respectively. The size range of a third distinct group, the mature larvae, can be generally approximated as between 60 and 76 mm, based on a maximum larval size of 76 mm and about a 25% size variation observed among trapped adults. Actual numbers in the 3 groups of 151, 39 and 22 seem to represent a reasonable decline in 40 Liu S a 30 bf ond LL. Oo cc a s 20 =) z 10 numbers through the development period. But even under the relatively uniform environmental condi- tion of cultivation some variation in development time would be expected. Some larvae between 20 and 60 mm in length, therefore, could be destined for 5 years or longer in the larval stage, even though the group designated as the third population pro- bably consisted mainly of 3-year-old larvae. All larvae smaller than about 10 mm were found in vertical tunnels in the vascular region to a soil depth of about 200 mm. None were found in dead tissues. Many larvae 10-15 mm in length were also associated with vascular tissues, but larger larvae exhibited little preference for particular areas of roots or crowns. Those longer than about 40 mm were sometimes associated with essentially un- —— Population 1 eee Population 2 --—— Population 3 —— Population 4 0 oo * ml oon olin op ep i [f 0 10 20 30 40 50 60 70 80 SIZE (mm) Fig. 2. Actual numbers (bars) of Prionus californicus by size class, from hop roots, and 4 hypothesized nor- mal populations based upon the same data using the EM algorithm for normal populations (curves). 24 J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 TABLE 1. Expected and observed numbers of Prionus californicus Mots. larvae in 4 hypothetical popula- tions calculated by the EM algorithm. Observed Number in Interval Expected Number iny Interval Population Number in Loss Gain Population i 148 0 Z 2 36 ate 9 3 3] 9 Ze 1. i Dp, 1 243 150 Lu 41 39 3. 30 oa 22 243 243 damaged roots showing they can move from one part of a root system to another. These larger larvae were occasionally found at depths to 50 cm. Control Considerations The presence of uninfected hops at a locality within 6 km of infected yards suggests that spread of P. californicus may be limited when occurrence of the host is not continuous, and that rotation of pro- duction between areas even relatively close together would be an effective control. Under those cir- cumstances it is highly unlikely that a serious in- festation would develop in the 15 to 20 year life ex- pectancy of a yard. Losses could also be reduced by allowing at least three years between hop plantings. Eyer (1942) found eggs to a maximum depth of 37 mm. In the present study essentially all larvae were found well below this level. Therefore applications of effective soil insecticides at plant bases as sug- gested by Eyer (1942) could provide control since newly hatched larvae would be exposed as they migrated through the soil before entering the crown or a root. Under Idaho conditions an insecticide ap- plication could be made beginning with 2-year-old hops on about July 15 and repeated annually. Eyer (1942) reported that P. californicus in New Mexico was most prevalent in light loam and sandy soils. These soil types are typical of the western Idaho hop producing area and may have con- tributed to the development of P. californicus as a serious problem. No natural enemies were observed to attack P. californicus in this study, but Leech (1947) has reported parasitism of an adult female by the dipteran, Sarcophaga rapax Walk. ACKNOWLEDGEMENTS We acknowledge the assistance of Dale Everson and Jim Norris in data analyses. This study was sup- ported by funds from the Idaho Hop Commission and the Hop Research Council. REFERENCES Crawford, R. F. and J. E. Eyer. 1928. The giant apple tree borer. New Mex. Agric. Exp. Stn. Bull. 168. 8 Pp. Doane, R. W. and E. C. Van Dyke, W. J. Chamberlin and H. E. Burke. 1936. Forest Insects. McGraw Hill Book Co., Inc. p:164-165. Essig, E O. 1926. Insects of Western North America. The MacMillan and Co., pp:449-450. Eyer, J. R. 1942. Life history and control of the giant apple tree borer. New Mex. Agric. Exp. Stat. Bull. 295. 14 pp. Keen, F. P. 1952. Insect Enemies of Western Forests. USDA Misc. Publ. 263, p 193. Leech, Hugh B. 1947. Sarcophaga rapax reared from Prionus californicus. Can. Ent. 79:141. ERRATUM In Vol. 80, 1983, in the article by Vernon and Houtman entitled, ‘Evaluation of sprayed and granular aphicides against the European asparagus aphid . . .’, the graphs from Figure 2 should appear above the caption of Figure 3 and vice versa. J. ENTOMOL. Soc. BriT. COLUMBIA 81 (1984), DEc. 31, 1984 ATTRACTION OF MALE FUMIBOTYS FUMALIS! TO FEMALES OF THE SPECIES?” H. G. DAVIS, L. M. MCDONOUGH Yakima Agriculture Research Laboratory Agric. Res. Ser., USDA Yakima, Washington 98902 K. S. PIKE Washington State University Irrig. Agric. Res. & Ext. Center Prosser, WA 99350 ABSTRACT Biological and behavioral studies show that female Fumibotys fumalis (Guenée) attract males of their species. Males responded to females between 11 p.m. and 3 a.m. and in greatest numbers between 12 p.m. and 1 a.m. Females were attractive 0.5 days after adult emergence and at least to the seventh day after emergence. Females were not attractive to males the evening following the night of 25 mating. INTRODUCTION The mint root borer, Fumibotys fumalis (Guenée), is widely distributed in North America from Nova Scotia, British Columbia, and Washington in the north to Florida, eastern Texas, and Utah in the south (Munroe 1976). The literature on this insect is limited. Forbes (1923) and Berry (1974, 1977) have reported on the biology, and Pike (1979, 1981) has reported on the chemical and cultural control of the pest. The taxonomy, morphology, and distribution of this moth has been described and reviewed by Munroe (1976). Before 1971, this insect had not been reported to be a pest of a cultivated crop, however, during that year it was found infesting peppermint in damaging numbers in the Willamette Valley of Oregon (Berry 1974). Since then it has spread to peppermint in other parts of Oregon and into central Washington. The importance of F. fumalis in the Pacific Nor- thwest has increased substantially since 1971. Detection, assessment of pest population density, and control have become necessary to the grower. Based on the vast literature on sex pheromones of Lepidoptera (Klassen et al. 1982) we presumed that either the male or female of F. fumalis produce a sex pheromone to attract the opposite sex. Because of the proven usefulness of sex pheromones for detection and population monitoring we began an exploratory study of the sex pheromone of this in- sect. Our first objectives were to provide essential biological and behavorial information prior to chemical studies of the pheromone. Tests were undertaken to determine: (1) whether males or females attract the opposite sex; (2) the time of day when flight activity in response to the sex pheromone occurs; (3) the range in age when call- ‘Lepidoptera: Pyralidae. ?Mention:of a commercial product in this paper does not constitute an endorsement by the USDA. Received for publication 11 July, 1984. SWashington State University, Paper No. 4337. ing occurs; and (4) if females are the attractive sex, whether mated females attract males. This paper reports the results of these tests. MATERIALS AND METHODS Mint root borer hibernaculae containing prepupae were collected in soil samples obtained from infested mint fields near Harrah, Washington, March 1982 and 1983. The hibernaculae were plac- ed in clear plastic shoe boxes on a 5-6 cm layer of moistened peat moss, covered with clear plastic lids and held in a rearing room at a temperature of 21°C, RH of 60%, and a daylength. of 16 h. After emergence, adult moths were sexed and maintained in corked glass vials (9.5x2 cm) containing a moistened mint leaf. Females selected for the field test were placed in wire screen cages (10x8x1.5 cm) which were suspended by a wire from the top of Pherocon IC® sticky traps equidistant between the top and bottom of the trap. The traps were suspended from a moveable metal arm attached to an iron rod stake. Each trap was positioned directly above the mint foliage, 45-60 cm above ground in the same field from which the hibernaculae were collected. In tests to determine which sex was attractive, males or females (one male or female/trap) were placed in three traps per sex with three non-baited traps during 1983 on 7/21, 7/26, 7/27, 8/13 and 8/14. Each insect was used for one night (9 p.m. to 9 a.m.). To determine the time of moth flight activi- ty, caged females (One female/cage) were placed in each of four traps on July 6, 8, and in each of three traps on July 9, 1982 for 12h. (9 p.m to9 a.m.), and the catches were counted hourly from 10 p.m. to 7 a.m. The temperature was recorded during the test period on a hygrothermograph (Belfort Instrument Co.; Baltimore, MD) in a louvered shelter in the mint field. For the experiment to determine the number of days after adult emergence that females will call and attract males, all females were careful- ly segregated according to age after emergence. 26 J. ENTOMOL. Soc. Brit. COLUMBIA 81 (1984), DEc. 31, 1984 Temperature (°C ) ) q a 15 2 40 35 300 (oe) jo) N = —a 3 \o) O > e) =< j=) J ro) z N 3 N (o) BO ) jo) je) N > pel rab) mam oF a> S i= = (2) je) Tv N (o) [o) ie) N je) @) op) (2) S N an - S) “A = 2400 2300 e) ie) N ie) v Q © s desy/jyuBneo saew x Fig. 1. Flight activity as a function time of day when F. fumalis (Guenée) were attracted to caged virgin females. O, mean number of moths captured per trap. There were 3, 4, and 5 replications for July 12, 19 and 22, respectively. Maximum trap captures were significantly different (P = 0.05, by Dun- can’s multiple range test) from adjacent lower values which were also significantly different from the next lower values, temperature variation. Harrah, WA, 1982. © bf N N J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 Wai TABLE 1. Variation in trap catch of male F. fumalis when unmated females used as attractants were of dif- ferent ages in a mint field near Harrah, Washington, July 1982. re LE K— Age after emergence in days No. traps S catch/tra 025 1 2 7 3 6 4 5 5 1 6 3 7 1 13 28 38 32 9 38 23 When the relative attractiveness of mated and un- mated females was compared, the mated females were obtained by placing them in cages with males. After the field tests, all females were dissected and checked for the presence of spermatophores. RESULTS AND DISCUSSION Traps baited with virgin females captured an average of 21.3, 34.0, 23.3, 26.0, and 31.3 males/trap and no females during five separate 12 h periods, while none of the male baited traps cap- tured males or females; unbaited traps caught no males in the three of the 12 h periods and 0.3 male/trap in each of the two other periods of 12 h. Consequently, the sex pheromone is produced by females to attract males. In tests to determine the time of day of flight ac- tivity (Fig. 1), moths were captured between 11 p.m. and 3 a.m. with signifcantly greater captures occurring between 12 p.m. and 1 a.m. The temperatures during the time of flight activity for the three nights ranged from 11-21°C. On the third night, 20 July, teperatures were lower during the flight period than on the first two nights, and flight acticity was considerably less than on the previous evenings (Fig. 1C). Traps baited with females caught males when the females ages varied from 0.5 to 7 days after emergence (Table 1). Females appear to be about constant in attractiveness during these ages, but our tests are not definitive in this respect because we could not obtain enough females from our small col- ony for adequate replication for ages 0.5, 5 and 7 days. Only unmated females attracted males. During the day following mating, none of the traps (a total of nine in three separate tests) baited with mated females caught males while the nine traps with un- mated females caught a total of 21, 48, and 74, males respectively. The biological and behavioral data presented here establish; (1) that females attract only males into traps while males do not attract either sex into traps; (2) that males respond optimally to females between 12 midnight and 1 a.m. (2400 and 100 h); (3) that females are attractive at least from 0.5 to 7 days after adult emergence and; (4) that mated females do not attract males during the day follow- ing mating. This information should be useful in the development of a monitoring system based on traps baited with the sex pheromone of F. fumalis. Such traps would be an asset to scientists and growers in detecting and assessing infestations of F. fumalis particularly in new peppermint plantings and in areas not now infested. REFERENCES Berry, R. E. 1974. Biology of Pryausta fumalis on peppermint in Oregon. Ann. Ent. Soc. Amer. 67:580-582. Berry, R. E. 1977. Insects on Mint. Pacific Northwest Cooperative Extension Publication No. 182. 15 pp. Forbes, W. T. M. 1923. The Lepidoptera of New York and Neighboring States. Memoir 68. Cornell Univ. Agric. Exp. Stn. Ithaca, N.Y. 729 pp. 28 J. ENTOMOL. Soc. Brit. COLUMBIA 81 (1984), DEc. 31, 1984 Klassen, W., R. L. Ridgeway, and M. Inscoe. 1982. Chemical Attractants in Integrated Pest Management Programs. In Insect Suppression with Controlled Release Pheromone Systems A. F. Kydonieus and M. Beroza eds. pp. 13-130. CRC Press Inc. Boca Raton, Florida. Munroe, E. 1976. Pyraloidea. In The Moths of America North of Mexico., Pyralidae (part), Fascicle 13.2A:26-28. Pike, K. S. 1979. Peppermint, Fumibotys fumalis, control, Washington Insecticide and Acaracide 4:88. Pike, K. S. and L. W. Getzin. 1981. Persistence and Movement of Chlorpyrifos In Sprinkler-Irrigated Soil. J. Econ. Entomol. 74:385-88. BIOLOGICAL CONTROL OF THE EUROPEAN FRUIT LECANIUM, LECANIUM TILIAE (HOMOPTERA: COCCIDAE), IN BRITISH COLUMBIA BRYAN P. BEIRNE Simon Fraser University, Burnaby, B.C. V5A 186 In 1928 and 1929 Glendenning (e.g., 1934) released specimens of the parasitic encyrtid Blastothrix sericea (Dalm.) from England in an in- tense and long-lasting outbreak of Lecanium tiliae (L.) in the Vancouver district of British Columbia. The infestation then collapsed: scale populations decreased from an average of 57 per 50 cm of branch in 1930 to virtually none in 1931. Parasitism of the scale increased from 25 per cent in 1930 to 99 per cent in 1983. This was later quoted widely as a classic example of successful biological control. However, the subsequent appearance of long- lasting outbreak of L. tiliae in the Vancouver district showed that it was not in fact an economic success. Flanders (1970) concluded that the numbers of specimens of B. sericea that were releas- ed were too small to have had any influence in con- trolling the 1920’s infestation, leading Rubin and Beirne (1975) to conclude that the increased percen- tage parasitism in the early 1930's was a conse- quence rather than a cause of the dramatic decrease in the scale population. The natural enemies of L. tiliae were studied by Rubin and Beirne (1975) in 1969-72 in an infesta- tion in the Vancouver district that began about 1964. The dominant parasite was the only species of Blastothrix found. It was identified by E. S. Sugon- jaev as B. longipennis (Howard), a native North American species that had earlier been regarded as a synonym of the European B. sericea. Rubin and Beirne deduced from this that B. sericea had not become established in the original biological control attempt which therefore was a technical failure as well as an economic one. Sugonjaev (1983) recently reviewed the genus Blastothrix in North America and stated that the species from British Columbia that was earlier iden- tified as B. longipennis is neither that species nor B. sericea but is B. britannica Girault, a parasite of several species of lecanium scales in Europe and not previously known from North America. Sugonjaev suggested that it had been introduced originally by Glendenning as B. sericea, became established, and subsequently spread into Washington and Oregon. Rubin and Beirne (1975) suggested that L. tiliae was still a potential subject for successful biological control in Southern British Columbia and Sugon- jaev (1983) now suggested that the true B. sericea would be suitable for introduction, since in Europe it is known to parasitize L. tiliae only and it has not been found in North America. This might now be done, some 60 years after it was first proposed by Glendenning. REFERENCES Flanders, S. E. 1970. Observations on host plant induced behaviour of scale insects and their endoparasites. Can. Ent. 102:913-926. Glendenning, R. 1934. On the control of Eulecanium coryli (L.) in British Columbia by the parasite Blastothrix sericea (Dalm.). Proc. 5th Pac. Sci. Cong. 5:3543-3545. Rubin, A., and B. P. Beirne. 1975. Natural enemies of the European fruit lecanium, Lecanium tiliae (Homoptera: Coccidae), in British Columbia. Can. Ent. 107:337-342. Sugonjaev, E. S. 1983. [A review of the genus Blastothrix Mayr (Hymenoptera, Encyrtidae) in North America]. Rev. d’Ent. URSS 62:601-609. J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), Dec. 31, 1984 29 EMERGENCE BEHAVIOUR OF PHOBOCAMPE SP. (HYMENOPTERA: ICHNEUMONIDAE), A LARVAL ENDOPARASITOID OF OPEROPHTERA SPP. (LEPIDOPTERA: GEOMETRIDAE) L. M. HUMBLE Graduate Student Department of Biology University of Victoria Victoria, B.C., V8W 2Y2 Phobocampe sp. was first recorded as a larval parasitoid of Operophtera species on southern Van- couver Island by Gillespie and Finlayson (1979). It was found to be the most important parasitoid of Operophtera spp. in 1976 and 1977 (Gillespie and Finlayson 1981). The large numbers of Phobocampe reared from a mixed collection of winter moth, O. brumata (L.), and Bruce span- worm, O. bruceata (Hulst), indicated that this in- ternal parasitoid attacked the introduced winter moth as effectively as its native host, the Bruce spanworm. Since final-instar Phobocampe larvae emerge from final-instar host larvae, the Operophtera species attacked in 1976 and 1977 could not definitely be determined from the mass- reared specimens (Gillespie and Finlayson 1981). The purpose of this paper is to describe the uni- que emergence behaviour of the final-instar larva of Phobocampe and to provide additional host associa- tion data for this parasitoid. Willow branches bear- ing Operophtera larvae parasitized by Phobocampe were brought into the laboratory for observation. The emergence and cocoon-spinning behaviour of the final-instar parasitoid larvae were observed and photographed during early June, 1982. Camera lucida drawings were prepared from selected 35 mm colour transparencies to illustrate the emergence sequence of the Phobocampe larva. Operophtera larval remains close to Phobocampe cocoons were collected by searching foliage and branches of willow. Additional host remains were obtained by individually rearing field collected host larvae parasitized by Phobocampe. The Operophtera larval remains were mounted on points and the arrangement of larval ocelli examin- ed under a dissecting scope fitted with a filar micrometer at 50X magnification. The larval ocellar characters described by Eidt and Embree (1968) were used to determine the host species. During the late stages of Phobocampe larval development, the parasitized caterpillars exhibit behavioural changes which allow them to be easily identified. Prior to parasitoid emergence, the parasitized host larvae are found hanging head down within the foliage (Fig. 1). The prolegs of the caterpillars are attached to a layer of silk, apparent- ly spun by the larvae themselves, on the underside of a leaf or branch. The Phobocampe larva can be seen moving within the host’s skin at this time; areas of the host’s body occupied by the parasitoid larva appear grayish and the remaining regions pale white. The head of the ichneumonid larva is within the posterior abdominal segments of the host, feeding on the remaining host tissue. Prior to the emergence of the Phobocampe larva, a bulge appears on the ventral surface of the host larva, anterior to the prolegs of the sixth abdominal segment (Fig. 2). The parasitoid larva uses its man- dibles to rasp through the host’s integument at the site of the bulge, taking 15-30 minutes to break through. Once the initial opening is made, the parasitoid larva forces itself out through the open- ing, alternately shortening and lengthening its body segments to move them through the opening. These movements continue until the thorax and first 2-3 abdominal segments are free of the host cuticle (Fig. 3). The parasitoid larva then arches its head caudal- ly and downward, looping its head and anterior thoracic segments in a direction along and under one side and then up the other side of its body, spin- ning a strand of silk around its body (Fig. 4). These spinning movements produce a “sling” of silk (Fig. 5) which suspends the parasitoid larva below the leaf or branch. Once the Phobocampe larva has spun the first loop of the sling, it anchors the anterior part of its body using both the sling and the leaf surface, then pulls more of its abdomen free of the host. Sling spinning continues, as more of the parasitoid larva is freed, until it is completely free of the collapsed host integument (Fig. 6). The Phobocampe larva can move up to 2 cm from the host remains, suspended in its silk sling beneath the leaf blade, before spinning its own cocoon (Fig. 7). The elapsed times from the rupture of the Operophtera larval integument to the beginning of construction of the parasitoid cocoons, for two emergence sequences timed in the laboratory, were 1] and 25 minutes. The cocoon spinning behaviour of this Phobocampe species was described by Gillespie and Finlayson (1979). Eidt and Embree (1968) showed that the ar- rangement of ocelli I and II relative to ocelli IV and VI could be used to separate most larvae of the winter moth and Bruce spanworm. Imaginary lines drawn through the two pairs of ocelli were usually parallel in the winter moth (90% of examined lar- vae) and usually diverged caudad in Bruce span- worm (93% of examined larvae). Some overlap of the ocellar characters was evident, with the lines 30 J. ENTOMOL. SOc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 4 Figs. 1-4. Initial stages of emergence sequence of Phobocampe sp.: 1, endoparasitized Operophtera larva attached to a leaf while Phobocampe larva completes feeding; 2, Operophtera larva with ventral bulge (arrow); 3, emerging Phobocampe larva with thorax and first two abdominal segments free; 4, a, Phobocampe l\arva attaching first silk strand to undersurface of leaf, b, diagrammatic representa- tion of head movements of the Phobocampe larva during sling spinning. J. ENTOMOL. SOC. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 31 2 mm 7 Figs. 5-7. Final stages of emergence and site of cocoon construction of Phobocampe sp.: 5, a, final-instar larva of Phobocampe using sling to free itself from the remains of the host larva, b, diagrammatic cross-section of Phobocampe larva suspended in sling; 6, Phobocampe larva free of host remains; 7, site of cocoon construction with collapsed sling remnants between Phobocampe cocoon and host remains. 39 J. ENTOMOL. SOC. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 diverging caudad in 5% of the winter moth larvae and parallel in 3% of the Bruce spanworm larvae examined. In this study the remains of 44 Operophtera larvae associated with Phobocampe cocoons were recovered. The arrangement of the ocellar pairs was parallel in 36 of the head capsules, slightly divergent caudad in 7 specimens and was strongly divergent caudad in a single specimen. The proportion of O. bruceata represented in the recovered remains cannot be determined exactly because the character overlaps as described between the two Operophtera species. However, these data indicate that most of the Phobocampe sp. present used O. brumata as a host. REFERENCES Eidt, D. C. and D. G. Embree. 1968. Distinguishing larvae and pupae of the winter moth, Operophtera brumata, and the Bruce spanworm, O. bruceata (Lepidoptera:Geometridae). Can. Ent. 100:536-539. Gillespie, D. R. and T. Finlayson. 1979. the function of the caudal appendage in cocoon jumping in Phobocampe sp. (Hymenoptera: Ichneumonidae:Campopleginae). J. Entomol. Soc. Br. Columbia. 76:39-42. Gillespie, D. R. and T. Finlayson. 1981. Final-instar larvae of native hymenopterous and dipterous parasites of Operophtera spp. (Lepidoptera:Geometridae) in British Columbia. Can. Ent. 113:45-55. BOOK REVIEW THE MOSQUITOES OF BRITISH COLUMBIA BY PETER BELTON Handbook 41, British Columbia Provincial Museum. Victoria, B.C. 1983, p. 189 It is a pleasure to report a second volume on in- sects in this handbook series — a series which so far has had 18 volumes on plants (including fungi and algae), 15 on vertebrates, five on marine in- vertebrates and one on marine life. I hope more of the insect fauna will be treated before long. The work should succeed admirably in_ its primary aims — to allow identification of mature larvae and females of the species of British Colum- bia, to outline their distribution within the pro- vince, and to provide a brief account of the biology of the group as a whole and of the individual species. The introductory sections are fully ade- quate; they cover the usual subjects of biology, history of mosquito study in the province, life zones, management (i.e., control), collection and preser- vation of the various stages, and anatomical terms. An unusual but interesting additon, by E. M. Belton, is “Mosquitoes in the Culture of the Nor- thwest Coast Indians”. A useful innovation consists of several blank pages; in this way the larval figures for each species except those of Anopheles face the description of the species. The drawings appear to be sufficient in number and detail to allow for ready identification of females and larvae. Two omissions are unfortunate, One is lack of treatment of the males. The author is correct in say- ing they are less often encountered than females, but half the specimens reared from larvae or pupae are males, and badly rubbed males can be much more reliably identified than can similar females. The author perhaps felt that the preparation of drawings of male terminalia was not worth the ef- fort, but the drawings in Wood et al., The Mos- quitoes of Canada, to which users of this handbook are referred for identification of males, could almost certainly have been used. The other regrettable omission is of distribution maps. The general distribution within the province is outlined for each species, but maps would have allowed the distributions to be much more quickly perceived, would have indicated which parts of the province are poorly surveyed, and would almost certainly have provided a greater incentive for fur- ther collecting. I think four maps to a page would have been possible; with non-overlapping species on one map, 10 pages of maps would probably have been adequate for the 46 species treated. One surprising statement should not go unremarked: “This order (Diptera) has about 67 families”. Williston’s Manual of Nearctic Diptera (1908) recognized 60 families, Curran’s Manual (1934) 83, the recent Agricultural Canada Manual (1981) 108, and some European authors recognize 120 or more. Not even the most enthusiastic lumper can make a reasonable case for only 67. J. R. Vockeroth March 8, 1984 J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 33 DEFOLIATION AND MORTALITY CAUSED BY WESTERN SPRUCE BUDWORM: VARIABILITY IN A DOUGLAS-FIR STAND R. I. ALFARO, T. L. SHORE AND E. WEGWITZ Agriculture Canada Pacific Forest Research Centre 506 West Burnside Road Victoria, B.C. V8Z 1M5 ABSTRACT Variation in Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) defoliation and mortality caused by the western spruce budworm (Choristoneura occidentalis [Freeman]) was measured in sequential annual surveys of a stand near Pemberton, British Columbia. The implications of this variability in designing defoliation and mortality surveys is discussed. RESUME On a mesuré, au moyen de relevés annuels successifs, dans un peuplement prés de Pemberton, en Colombie-Britanique, les variations de la mortalité et de la défoliation causées par la tordeuse occidentale de |’épinette (Choristoneura oc- cidentalis [Freeman]) chez le douglas taxifolié (Pseudotsuga menziesii [Mirb.] Franco). On discute de |’influence de ces variations sur la planification de relevés ultérieurs de la det de la mortalité. INTRODUCTION The western spruce budworm (Choristoneura oc- cidentalis [Freeman]) is a recurrent defoliator of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) and other coniferous trees, causing tree mortality, growth loss and stem deformities (Alfaro et al. 1982; Ferrell and Scharpf 1982; Van Sickle et al. 1983). Budworm infestations are often extensive. The last epidemic in British Columbia (B.C.) reached a maximum area of 226 000 ha in 1976 (Harris et al. 1984). Although defoliation and mortality vary, both within and between stands, few measurements of this variability and its effect on sample size have been reported in western North America. Intensive surveys were conducted by the late Mr. J. A. Baranyay, of this centre, to quantify defolia- tion in an infestation that started in 1970 and lasted until 1974 at Railroad Creek, 32 km northwest of Pemberton, B.C. The area was re-surveyed in 1981 to determine the extent and distribution of tree mor- tality. This paper reports and discusses the variabili- ty of defoliation and tree mortality caused by the budworm infestation in this stand. Results from studies based on a 420-tree sample within the area covered by these surveys were reported by Alfaro et al. (1982), Van Sickle et al. (1983) and Alfaro et al. (1984). Annual defolia- tion records, maintained on these trees from 1970 to 1980, indicated that the latter year marked the return to normal foliage growth following the ef- fects of defoliation (Alfaro et al. 1982). METHODS Surveys were conducted each year from 1971 un- til 1973 in an area of approximately 54 ha of pure, 80-year-old Douglas-fir at Railroad Creek. The survey design consisted of 5.06 m radius (80.4m?) plots, spaced in a systematic grid every 43 m. The number of plots (number of trees in brackets) measured each year was 135 (470), 115 (378) and 122 (406) in 1971, 1972 and 1973, respectively. Data collected in each plot included tree species, diameter, height, mortality and crown class. The live crown was ocularly divided into 4 vertical levels and defoliation was estimated to the nearest 10% of the total foliage in each level. Defoliation for each tree was then calculated as the arithmetic mean of the four crown-level estimates. Average tree defoliation and associated variance were calculated using formulae for cluster sampling with unequal cluster size (Scheaffer et al. 1979). To assess the relative efficiency of cluster versus single tree sampling, mean defoliation and variance were recalculated on a sample of one randomly selected tree out of each plot. Mean defoliation and variances were compared to those obtained using all plot trees. In 1981, the area was re-surveyed by variable radius plot cruise (BAF 5) to determine the extent of basal area mortality. Tree data collected included species, crown class and mortality. All four surveys followed a similar ground cruise design, but because plots were not permanently identified, location of the plot centers varied from year to year. Since tree mortality caused by budworm was reported to be more intense on the smaller, sup- pressed and intermediate trees (Alfaro et al. 1982), the spatial distribution of these crown classes in the stand was studied by calculating the dispersion in- dex: ID = S?(n-1)/x (Southwood 1978). J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 34 9°€ = G’e ett rag 80T Lat ae OYA S°TT (€°€)9°9S (8°€)S°9S (f°72)0°9S SI3qSN[D Seetqz vTsuTs Siay;sn{toO €L6T 80T L°eT (9°C)S°ES $903} eTsutsS saazysnTto $903q 8T3uts cLol cel cel 8° 02d S°8t (2°€)8° 972 (e°e)E°S? TL6I Jeax uotTAeT[Tojeq ‘wWaIOMpng sonids u1s}sam ay} Aq pazel[OJop pue}s I1j-sejsnoq e ul Zuljdures Jaysnjo pue 901} asus YM poule}go sonshye}s Suljdwies pue (syeyxouiq UI [AIoWUI VDUaPIFUOD % CG) UOTeI[OJap y% Uva] ‘T AIAVL Jeysn{[9 Jjed S90lT] ‘ON °*3AY ezZTtS oTdwes uOTRETASP PISPUeRS UOTRETTOJOg uePeH J. ENTOMOL. Soc. Brit. COLUMBIA 81 (1984), Dec. 31, 1984 35 RESULTS AND DISCUSSION Defoliation Mean defoliation, as estimated by plot sampling, increased from 24.8% in 1971 to 54% in 1972 and 56.6% in 1973 (Table 1). Standard deviations for the same years, were 20.8, 11.5 and 17.7%. The coefficient of variation dropped from 83.9% in 1971 to 21.3% in 1972 and 31.3% in 1973. Recalculation of the estimate, using one random- ly selected tree from each plot, yielded mean defoliation estimates that were less than 1% dif- ferent from those obtained using all plot trees. Stan- dard deviation was lower in 1971 (18.5%) and higher in 1972 (13.7%) and 1973 (20.5%) in single tree sampling relative to plot sampling. These results indicate that the original survey design which involved defoliation estimation of all trees in the plots was not justified and led to over- sampling. Single tree sampling could have provided estimates of almost identical precision. The increasing defoliation in the stand, from 1971 to 1972 and 1973, was reflected in the increas- ing frequency of plots with mean defoliation precentages in the 51-75% and 76-100% classes (Table 2). The spatial distribution of defoliation was highly variable in 1971 when defoliation was lower and the infestation was starting. Defoliation was more uniformly distributed across the stand in 1973 when 65.2% of the plots had mean defoliation of 51% or more (Table 2). The variability obtained with single tree sampl- ing can be discussed in the context of sample size determination. Two approaches are possible when determining the number of plots required to achieve a desired level of precision in the estimation of average stand defoliation. The first method, using formula (1) (Husch et al. 1972) calculates sample size by setting the error bound as a fixed proportion of the mean: t? cv? “(AE %)? (1) NUMBER OF TREES Us (eo) 5 10 where t = Student’s t value at the required confidence level cv = coefficient of variation AE% = allowable error as a percentage of the mean Thus, in our case, the sample size (number of trees) required to be 95% confident that the estimated average defoliation was within 10% of the mean, was 204, 27 and 51 trees in 1971, 1972 and 1973, respectively. Since mean defoliation for these years was 25.3, 53.5 and 57.5%, these sample sizes theoretically would provide an error bound of 2.5%, 5.4% and 5.8% defoliation for each of the years. Estimation by eye of the defoliation of in- dividual trees is an inexact method; individual estimates could at best be expected to come within 10% of the true value (Silver 1959). As a result, precision requirements related to the mean can be unrealistic when defoliation is light. This was the case in the 1971 estimate. A more realistic ap- proach, discussed by MacLean and Ostaff (1983), consists of setting the error bound on the estimate as an absolute value, independent of the mean. Using formula (2) (Husch et al. 1972) to estimate mean defoliation in this stand to + 10% , only 15, 9 and 18 trees would have been required in 1971, 1972 and 1973, respectively. This would have resulted in considerable savings in time and effort. t?SD? (AE)? (2) = Student’s t value at the required confidence level SD = standard deviation AE % = allowable error in the same units as the mean Assuming the maximum standard deviation of 20% found in these defoliation surveys, the number of trees required to estimate mean defoliation to within absolute error bounds from 5 to 25% defoliation (i.e. using formula 2), is given in Fig. 1. Sixty one trees are required to estimate mean n= where t 15 20 25 REQUIRED PRECISION ( + % DEFOLIATION ) Fig. 1. Relationship between sample size and precision when defoliation standard deviation is 20% (max- imum observed in this study). 36 J. ENTOMOL. SOC. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 Railrood Creek % MORTALITY oe) ® 1-25 @ 26-50 Fig. 2. Distribution of basal area mortality of Douglas-fir in plots surveyed in 1981, after the stand recovered from a western spruce budworm infestation that lasted from 1970 to 1974. TABLE 2. Frequency distribution of the plots in five defoliation or basal area mortality classes. Defoliation or Defoliation BA Mortality Mortality Class (%) 1971 1972 1973 1981 0 1 (¢( 0.8)* 0 ( 0.0) 0 ¢ 0.0) 35 (30.7) 1-25 61 (49.6) 300228) 6 ( 5.3) 32 (28.1) 26-50 49 (39.8) 32 (29.6) 33 (29.5) 34 (29.8) 51-75 11 ( 9.0) 69 (63.9) 54 (48.2) 10 ( 8.8) 76-100 1 ( 0.8) 4 ( 3.7) 19 (17.0) 3 ( 2.6) Total 123 (100) 108 (100) 112 (100) 114 (100) * Percentages are given in brackets. 37 J. ENTOMOL. SOC. BRIT. Co.umBiA 81 (1984), Dec. 31, 1984 A] eer B°TEe cot 6°12 BL cS G*et O°V~ (%) ey/7u BY / 7 AOD qs ueon T86T -e}saJuy ‘UIOMpNq gonids ula}saM oy} Aq payel[ojop 81 coe 7° 9 029 cl c°O BL O°9€ T° 99 (%) ey/7u BU / 7 AO qs ueoW eL6l 79 €°%d O°8t s = 0°0 79 G°¥d O°8e (%) ey/7u BU /7u AO qs ueoR clot 99 G’Tt ely T230OL 009 y°? ¥°O peod 99 G EL 6°99 SATTV AO qs Ubon es i) eae aa ‘PLOT 99 OLET Woz pore] UOH pur}s 11j-sepsnoqg e Jo shaAins Moy ut AyyeyWOU vale [eseq pur vare [eseq 10j (* AD) UOTBLIVA JO WUSTOT}Jo00 pue ((q'S) uoRetAep prepurys ‘ues *€ ATAVL 38 J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), Dec. 31, 1984 defoliation to + 5% defoliation. The number of trees required is reduced to between 5 and 10 for precision levels of 15 to 25% defoliation. Further studies in stands of different characteristics, using different plot sizes are necessary to derive sample curves of more general applicability. However, in the absence of these data, the curve in Fig. 1 can be used as a preliminary guide in the design of western spruce budworm defoliation surveys. Mortality Tree mortality during the three defoliation years covered by these surveys was less than 1% of the basal area per ha in each year; however mortality by 1981 averaged 7.8m?/ha (24.5% of the basal area per hectare) (Table 3). Mortality attributable to bark beetle or to other agents was low throughout the period (Alfaro et al. 1982); therefore, most mor- tality was attributable to budworm defoliation. Plot to plot variation in basal area mortality was high in the 1981 survey but negligible in other years. About 30% of the plots had mortality levels in the 0, 1 to 25 and 26 to 50% basal area mortality classes, while 10 plots (8.8%) had basal area mor- tality between 51 and 75% and 3 plots (2.6%) had more than 75% of their basal area in dead trees (Table 2). Coefficient of variation for basal area mortality was 102% (Table 3). This variability resulted in error bound of 1.45 m?/ha or 18.5% in the estimation of the total dead basal area in the stand (7.8 m*/ha). To reduce that error to a fixed level of 1 m?/ha (12.8%), 240 plots would have been required. Most mortality occurred among small, suppressed and intermediate trees (Alfaro et al. 1982). Using an index of dispersion to test the departure from ran- domness of the distribution of these trees (Southwood 1978) we concluded that trees of the suppressed and intermediate crown classes were distributed randomly in the stand. This random distribution of the smaller trees may explain the highly variable spatial distribution of mortality in the stand (Fig. 2). The uneven thinning effect resulting from such a mortality pattern may be silviculturally unacceptable. In conclusion, assessment of the level of defolia- tion of a stand can be performed by a single-tree sampling scheme. This sampling could be done at the same time that other surveys are conducted in an infested stand. An optimum arrangement might be to estimate defoliation on one tree per plot on randomly selected plots during a mensurational survey aimed at assessing the stand volume at risk. Since mortality occurs in the late stages of a bud- worm infestation and continues even after the population collapses, a different survey is required to determine the mortality level in the stand. Mor- tality surveys would be required to assess the total impact of an infestation and to enable management decisions such as early logging or site rehabilitation. ACKNOWLEDGEMENTS The authors would like to acknowledge the con- tribution of the late J. A. Baranyay of this centre who conducted the 1971-73 surveys. REFERENCES Alfaro, R. I., G. A. Van Sickle, A. J. Thomson and E. Wegwitz. 1982. Tree mortality and radial growth losses caused by the western spruce budworm in a Douglas-fir stand in British Columbia. Can. J. For. Res. 12:780-787. Alfaro, R. I., A. J. Thomson and G. A. Van Sickle. 1984. Quantification of Douglas-fir growth losses caus- ed by western spruce budworm defoliation using stem analysis. Can. J. For. Res. In Press. Ferrell, G. T. and R. F. Scharpf. 1982. Stem volume losses in Grand firs top killed by western spruce bud- worm in Idaho. USDA For. Serv. Pacific Southwest For. and Range Exp. Sta. Res. Pap. PSW-164. Harris, J. W. E., R. I. Alfaro, A. G. Dawson and R. G. Brown. 1985. The western spruce budworm in British Columbia 1909-1983. Agric. Can. Can. For. Serv. Inf. Rep. In Press. Husch, B., C. I. Miller and T. W. Beers. 1972. Forest mensuration. Ronald Press Co. New York. 410 pp. MacLean, D. A. and D. P. Ostaff. 1983. Sample size — precision relationships for use in estimating stand characteristics and spruce budworm caused tree mortality. Can. J. For. Res. 13:548-555. Scheaffer, R. L., W. Mendenhall and L. Ott. 1979. Elementary Survey Sampling. Duxbury Press, Massachusetts. 278 pp. Silver, G. T. 1959. Individual differences in estimating defoliation. Can. Dep. Agr. Res. Br. For. Bi. Div. Bi-mon. Prog. Rept. 15(3): 1-4. Southwood, T. R. E. 1978. Ecological methods. John Wiley & Sons, New York. 524 pp. Van Sickle, G. A., R. I. Alfaro, and A. J. Thomson. 1983. Douglas-fir height growth affected by western spruce budworm defoliation. Can. J. For. Res. 13:45-450. J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 39 FACTORS OF SUSCEPTIBILITY IN SPRUCE BEETLE ATTACK ON WHITE SPRUCE IN ALASKA E.. H. HOLSTEN State and Private Forestry, USDA Forest Service Anchorage, Alaska 99508 ABSTRACT Spruce bark beetle activity was monitored over 14 years on a transect through a mixed white spruce stand on the Kenai Peninsula, Alaska. Data confirmed bark beetle preference for attacking large-diameter, slow-growing spruce. Increased bark beetle activity was noted on north facing slopes; the least activity was on ridge tops. Moisture stress brought about by low soil temperatures is believed to be the cause for increased susceptibiity of white spruce to beetle attack on north facing slopes. A rudimentary guide is given to rate uninfested spruce timber for probable high or low losses if attacked by spruce beetles. INTRODUCTION The spruce bark beetle (Dendroctonus rufipen- nis [Kirby]) is the most devastating forest insect pest of white (Picea glauca [Moench] Voss), and Sitka spruce (P. sitchensis [Bong.] Carr.) in south-central Alaska. Beetles infested 130,000 hectares of forested land in 1983! of which 14,000 hectares occurred on Chugach National Forest on the Kenai Peninsula. Some of these areas such as the East Fork drainages (Fig. 1), have sustained chronic beetle infestations for the past 20 years (Crosby and Curtis 1968, Baker and Curtis 1972). Spruce beetles preferentially attack and breed in slow-growing, large diameter spruce where the spruce component of the stand is greater than 50 % (Schmid and Frye 1976, Werner et al. 1977). Recently, Hard et al. (1983) showed that on the Kenai Peninsula, diameter is not important for spruce susceptibility to attack, unless large diameter is related to slower than average cumulative radial growth in the last five years. Likewise, in the early stages of an outbreak, mean spruce radial growth is inversely related to the total number of trees of all species per hectare since trees in dense stands grow more slowly due to competition. Institute of Northern Forestry personnel established (early 1969) a transect through mixed spruce stands in the Dry Gulch Creek area on the Kenai Peninsula to evaluate the impact of a spruce beetle outbreak (Fig. 1). Losses were related to such stand factors as tree diameter and age. Forest Pest Management re-evaluated the transects in 1980 and 1983 when additional data were collected to deter- mine the influence of radial growth, stocking and aspect on spruce beetle attack. MATERIALS AND METHODS Description of study area: A chain-wide transect extended in a northerly direction traversing four main aspects: bottomland (BL), south-aspect slope (SA), ridge top (RT), and north-aspect slope (NA) (Fig. 1). Elevation along ‘Data on file with Forest Pest Management, USDA Forest Service, Anchorage, Alaska. the transect varied from 213 to 274 m above M.S.L. The stand was composed of white spruce, paper birch (Betula papyrifera Marsh.), and mountain hemlock (Tsuga mertensiana [Bong.] Carr). Average spruce diameter at breast height (dbh) along the transect was 27.7 + 11.7 cm and average spruce height and age were 19 + 6m and 133.5 + 34 years, respectively. Experimental design: Spruce greater than 10.2 cm dbh along the transect were labeled at breast height with numbered aluminum tags (366 trees). Diameters were recorded from each spruce as well as crown position and tree condition in relation to beetle ac- tivity as non-infested, infested, pitch outs, and bee- tle killed. Data were recorded in the early summers of 1969, 1970, 1974 and again in 1980 and 1983. Four variable plots (basal area factor,BAF = 10) were established in each of the four main aspects in 1983. Diameter at breast height of all species within each plot was recorded. An increment core, approx- imately 2.54 cm long, was removed from the uphill side at dbh from as many spruce as posible (297) along the transect. Cumulative width of the last five annual rings was measured, in the field, to the nearest 0.2 mm using a hand lens and ruler. Data compilations: Bark beetle attack was first analyzed on spruce trees along the transect over a 14 year period without regard to basal area, stocking, and aspect. Bark beetle attack was then compared between the four main aspects and their corresponding basal areas, stocking, and growth. RESULTS AND DISCUSSION Spruce diameters average 27.7 cm dbh along the transect. The diameters of spruce attacked and kill- ed by bark beetles over 14 years averaged 35.6 cm; uninfested spruce averaged 22.9 cm dbh (Fig. 2a). The tendency of spruce beetles to attack and kill large-diameter spruce is re-confirmed and is also demonstrated in Figure 2b, which shows that large- diameter trees are selected in the early years of an 40 J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 (9p) ree) oO oOo & ~~ 0 o ¢ o o a = o £ oO Ww =i Qa¢ YQ = es o c) 2] | @ dee - Portage Lake PFe) Yoiny hig = — as “= == a aN P4IBMag OL Fig. 1. 1983 spruce beetle infestations and location of the transect along the Dry Gulch drainage. outbreak and selection decreases thereafter. By 1974, diameters of attacked and killed trees averag- ed 27.9 cm dbh, which approximated endemic levels (Fig. 2b), when only 3% of the live spruce were killed. Beetle attack increased in 1977 along a powerline right-of-way adjacent to the transect (Holsten 1981). Average diameters of killed spruce increased from 31.8 cm. in 1980 to 38.4 cm in 1983 when 19% of the live spruce were attacked and kill- ed (Fig. 2b). Over the 14 year period, 161 tagged spruce (44%) were killed. J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 a1 38.0 35.6 33.0 30.5 27.9 DBH(cm) 25.4 22.9 ALL SPRUCE BEETLE n:217 UNIN. KILLED SPRUCE Fig. 2a. Condition of spruce over 14 years as related to diameter. Hard et al. (1983) found that as mean cumulative radial growth of spruce for the last five years was approximately 4 mm or less, the incidence of spruce beetle attacks resulting in tree mortality increased. Growth data from the Dry Gulch Creek transect support this finding (Fig. 3a,b). Average growth of all killed trees was 2.4 mm vs 5.0 mm for uninfested spruce. Pitch outs, or unsuccessfully attacked trees, showed an average growth rate of 4.6 mm, slightly lower than the uninfested spruce. Pitch outs occur when the density of attacking beetles is insufficient to overcome host resistance, or the host is growing vigorously and resists attack. Spruce beetles not only selected large-diameter spruce at the beginning of the outbreak, but also selected less vigorous spruce as reflected by the low cumulative radial growth (Fig. 3a). As the outbreak progressed and subse- quent beetle density increased, smaller diameter and faster growing spruce were attacked until the outbreak subsided in 1974. But with the increased beetle population density again in 1977, large- diameter and fast-growing spruce were attacked as most of the slow-growing spruce were already kill- ed. Growth rates of attacked spruce were substan- tially lower than uninfested spruce (2.5 mm vs. 5.0 mm, respectively) even at the apparent peak of the outbreak in 1983. Beetle attack was not uniform throughout the transect; increased mortality was apparent in cer- tain areas. Table 1 depicts beetle attack as related to aspect with reference to growth rate, diameter, basal area, stocking, and percent mortality. The NA site had the highest mortality (49% ) and the lowest average spruce growth rate (2.8 mm). Percent mor- tality decreased while spruce growth increased in the following order: NA, BL, SA, and RT which sustained only 20% mortality and had the highest growth rate (5.7 mm). Hard et al. (1983) found that mean radial growth of spruce was inversely related to the number of trees of all species per hectare. However, the results from the variable plots in this study indicated that high beetle attack and low growth were related to the lowest stocking (Table 1). Percent of spruce basal area in the stand was highest (67%) in the heaviest attacked areas and lowest (26%) in the lighter attacked stands on the ridge tops. Schmid and Frye (1976) have shown that increased percen- tage of spruce in the canopy increases the risk of 49 J. ENTOMOL. SOC. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 38.0 % 35.6 33.0 30.5 27.9 DBH(cm) 25.4 22.9 5 9 8 : : an 69 70 74 80 19 83 ¥%% renewed beetle attack along powerline % mortality of live spruce Fig. 2b. Average diameter of beetle-killed spruce by year. spruce beetle attack. Hard et al. (1983) showed that percent of spruce killed increased with the number of spruce greater than 24.1 cm dbh. The amount of spruce basal area in our study sites may affect susceptibility (more hosts to be attacked) but pro- bably does not affect growth rate unless spruce have different growth requirements from those of moun- tain hemlock in a mixed stand. If so, then “high” spruce basal area would be important in affecting growth of competing trees. The possibility exists that some additonal site fac- tor(s) is/are responsible for radial growth levels which are directly related to spruce susceptibility to beetle attack. Soil moisture is probably the most im- portant factor affecting tree growth. In most forest areas soil moisture levels are rarely optimal during a growing season since northern latitude soils are usually cold. It is known that water uptake by plants is reduced at low soil temperatures (Whitehead and Jarvis 1981). Water uptake can be reduced by 60% with a drop of 15°C in soil temperature. For P. sitchensis seedings, critical soil temperatures for transpiration and photosynthesis are around 1°C (Whitehead and Jarvis 1981). In northern environments, internal water stress during the dormant season often determines whether a tree survives when the ground is frozen and the foliage is exposed to excessive transpiration (Kozlowski 1968, Zahner 1968). Such a condition results in redbelt or winter desiccation and can oc- cur during warm winter or spring days. In less severe cases, internal water stress can become severe in winter, and recovery and cambial growth may be delayed in the spring. Safranyik et al. (1981) show- ed that when radial growth ceased due to moisture stress, the formation of callus tissue, traumatic resin ducts and wound periderm were prevented, significantly reducing host resistance to spruce beetles. Spruce beetles select weakened and stressed trees and the availability of such trees is necessary in the development of outbreaks (Safranyik et al. 1981). Their data suggest that spruce beetles can detect and respond to stress conditions (water stress) in live trees. It is possible that the observed low growth rates as well as the higher percent mortality along the NA portion of the Gulch Creek transect is related to water stress brought about by the low soil temperatures commonly encountered on north slopes (Buckman and Brady 1966). Soil J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 43 4 3 € E = = 2 > ve) c Oo 1 69 70 74 80 83 Fig. 3a. Condition of spruce as related to cumulative radial growth for 5 years. temperatures, recorded from a northeast aspect on the Kenai Peninsula, were as low as -6°C at a depth of 15 cm during June 1983 (Table 2)'. A possible condition for the Dry Gulch area could be: 1) from May-June, soil temperatures are very low (less than #1Personal communication — Dr. Richard Werner, Institute of Nor- thern Forestry, Fairbanks, AK 99701. 5 _ 4 = £ = 3 > Oo 2 ce SO 1 BEETLE KILLED PITCH OUTS 1°C) due to aspect, but ambient temperatures meet or exceed the flight threshold temperature for spruce beetles (16°C); and 2) soil moisture deficits exist because of increased transpiration and low soil temperatures; and 3) spruce beetles detect and suc- cessfully attack these water stressed trees. A rudimentary guide to rate uninfested spruce timber for probable high or low losses if attacked by ALL SPRUCE UNIN. SPRUCE Fig. 3b. Cumulative radial growth for 5 years of beetle-killed spruce by year. J. ENTOMOL. SOC. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 44 = = 7” _ ( ey iad) gu ¢ + €°OL gu Liyl + 2°02 gu 8 + L°02 gw Ol + 8°12 - eBeiy Teseg aonids ae = = = ( ey iad) gw y'6 + 9°6E gu o°8 + pHs gw o'k + 2°12 quis + L£°7s - eoly [eseg [eI0] swoiIs ST9 + 09ST swsaS 07S + L66 suoys ZyZ + 699 suo3s ZI¢ + pyS - (ey ied) B8utyxD0I3S wd p'OT + 2°92 Ws vecT ©. fo? 9,°0'9) O° EZ lia 7) + 2°05 - Had 2onidsg ‘s0ay (°sa4 GS) YMOID wu /£°Ss wu g°s WW PL Wu g°Z - [etpey sonids SATeT[NUN) °IOAV (vr=U) 02 (88=U) §Z (L8=U) br (OvI=U) 6p - AITTeIIOW JUSdI0q (LY) doy a8pis pue ‘(ys) adoys yoodse-yynos ‘(JTgq) puvyuroy0q ‘(WN) edojs yoodse-y}i0u ‘syoodse UIeU INO} 0} paj}e[al SB SONSTIa}ORIVYO pues pue AjTeIIOUI 9[}90q VONIdS *T ATAVL J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), Dec. 31, 1984 45 TABLE 2. Soil temperatures (°C) from a northeast aspect along Snug Harbor Road on the Kenai Penin- sula!, 1983. MAY (26-31) Depth Max Min Mean (cm) 15 - 1 - 2 -1.86 22 - 1 - 3 -1.81 9 +1 - 2 -0.50 6 + 3 0 +1.81 3 + 6 + 1 +2.91 ‘Data on file with the Institute of Northern Foresty, Fairbanks, AK 99701. spruce beetles can be based on these preliminary findings and those of others. High risk stands would be characterized by large diameter spruce, high spruce basal area, less than 4.0 mm cumulative radial growth the last five years, and a north aspect. A major precaution must be taken, however: these findings were developed from data collected in a single infestation and cannot be safely extrapolated to other areas until additional data from other areas on the Kenai Peninsula support the findings. Future studies should research such variables as elevation, JUNE Max Min - Mean = S ae - 6 -2.84 0 - 4 -1.67 + 4 ~ 4 +1.91 + 8 0 +4.55 +12 + 2 +6.89 ACKNOWLEDGEMENTS The establishment of the transect and the collec- tion of the first three years of data were carried out by Dr. Roy Beckwith of the Pacific Northwest Forest and Range Experiment Station. Special thanks go to Ken Zogas, Bob Wolfe, and Tom Ward of Forest Pest Management for their assistance in the collection of field data. I am grateful to D. Cur- tis, R. Werner, and J. Hard for reviews of early drafts of the manuscript. slope, soil type, soil temperatures, and proximity to tidewater in order to develop a regional system for risk rating spruce stands to attack by spruce beetles. REFERENCES Baker, B. H. and D. J. Curtis. 1972. Forest Insect and Disease Conditions in Alaska — 1972. Division of Timber Management Alaska Region. USDA Forest Service. 9 pp. Buckman, H. O. and N. C. Brady. 1966. The nature and properties of soils. the Macmillan Co., N.Y. 567 pp. Crosby, D. and D. J. Curtis. 1968. Forest Insect Conditions in Alaska during 1968. Division of Timber Management Forest Service, Alaska Region. USDA Juneau, Alaska. 7 pp. Hard, J. S., R. A. Werner, and E. H. Holsten. 1983. Susceptibility of white spruce to attack by spruce beetles during the early years of an outbreak in Alaska. Can. Journ. For. Res. 13:678-684. Holsten, E. H. 1981. Spruce Beetle: Chugach National Forest, Anchorage Ranger District, Forest Pest Management. Biol Eval. R10-81-4. Alaska Region 20 pp. Kozlowski, T. T. 1968. Water deficits and plant growth. Vol. I. Development, control, and measurement. Academic Press. Pgs 1-21. Safranyik, L., D. M. Shrimpton, and H. S. Whitney. 1981. The role of host-pest interaction in population dynamics of Dendroctonus rufipennis (Kirby) (Coleoptera: Scolytidae). Unpublished Proceedings on host-pest interactions. Aug. 24-27, 1981, sponsored by IUFRO and USSR Academy of Science. 24 pp. Schmid, J. M., and R. H. Frye. 1976. Stand ratings for spruce beetles. USDA For. Serv. Res. Note RM-309. App. Werner, R. A., B. H. Baker, and P. A. Rush. 1977. The spruce beetle in white spruce forest of Alaska. USDA For. Serv. Gen. Tech. Report PNW-71 13 pp. Whitehead, D. and P. G. Jarvis. 1981. Water Deficits and Plant Growth. Vol. VI. Woody plant com- munities. (ed. T. T. Kozlowski). Academic Press. Pgs. 49-152. Zahner, R. 1968. Water Deficits and Plant Growth. Vol. II. Plant water consumption and response. Academic Press. Pgs. 191-254. 46 DAMAGE BY TWO DOUGLAS-FIR CONE AND SEED INSECTS: J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 CORRELATION WITH CONE CROP SIZE G. E. MILLER, A. F. HEDLIN AND D. S. RUTH Canadian Forestry Service, Pacific Forest Research Centre, 506 W. Burnside Road, Victoria, B.C., V8Z 1M5 ABSTRACT Damage by the Douglas-fir cone moth, Barbara colfaxiana (Kearfott), in year N was significantly related to the size of the cone crop the preceding year (N-1) in the interior of British Columbia but not at the coast. Damage by the Douglas-fir cone gall midge, Contarinia oregonensis Foote, at the coast was also significantly related to cone crop size the preceding year. Fluctuations in cone crop size appear to limit populations of these cone insects. RESUME L’ampleur des dommages causés par le perce-cone du Douglas (Barbara col- faxiana [Kearfott]) au cours de l’année N est étroitement liée a l’ importance de la récolte de cones de l’année précédente (N-1) en Colombie-Brittanique, exception faite de la région cétiere. I] en va de méme pour les dommages causés par la cécidomyie des cones du Douglas (Contarinia oregonensis Foote) sur la cote. I] sem- ble y avoir un rapport entre l’importance de la récolte de cénes et les populations de ces insectes. INTRODUCTION Douglas-fir cone moth, Barbara _colfaxiana (Kearfott) (Lepidoptera: Olethreutidae), and Douglas-fir cone gall midge, Contarinia oregonensis Foote (Diptera: Cecidomyiidae), are the two most frequent and damaging seed pests of Douglas-fir, Pseudotsuga menziesii (Mirb.) Franco, in British Columbia. Douglas-fir cone moth occurs most com- monly in dry interior areas whereas Douglas-fir gall midge is most common in wet coastal areas (Hedlin et al. 1980). Both insect species are univoltine although in- dividuals may diapause for more than one winter (prolonged diapause) (Hedlin 1960, 1961). Adults of each species emerge and oviposit when seed cones are open to receive pollen, in April and early May. Feeding by cone moth larvae begins in May and is completed by mid July at which time pupation takes place. The cone moth overwinters as a pharate adult (Sahota et al. 1982) in the cones. Larval feeding by cone gall midge, which causes gall for- mation on cone scales, occurs from May to September. When the matured and dried cones are wetted by rain in September the fully-developed larvae leave them to overwinter in the duff. Damage by cone moth is the result of direct con- sumption of seeds (Hedlin 1960) while gall forma- tion by cone gall midge inhibits ovule development and impairs seed extractability (Johnson and Heik- kenen 1958). Cone and seed production by Douglas-fir varies widely over a period of years. For example, in the Vancouver Forest Region between 1935 and 1974, three heavy crops, five medium crops, 10 lights crops, nine very light crops, and 12 crop failures oc- curred (Dobbs et al. 1976). Variations in cone and seed abundance affect both populations of and damage by cone and seed insects attacking pines, Pinus spp., and Norway spruce, Picea abies (L.) Karst. (Mattson 1971, 1980; Forcella 1978, 1980; Annila 1981), but relationships between cone crop size and damage by Douglas-fir cone moth and cone gall midge have not been reported. The objective of this study was to determine whether or not damage by these insect species was related to cone abundance. MATERIALS AND METHODS Cones were collected in August or September in the interior near Keremeos, B.C., between 1959 and 1982 and at the coast near Lake Cowichan, B.C., between 1957 and 1982. No cone collections were made in 1971 and 1972 at the coast or in 1972 and 1976 in the interior. The number of cones col- lected each year depended on the size of the cone crop and ranged from 20 to 1080. The number of sample trees ranged from 3 to 40. The cones were sliced longitudinally along their axes (Winjum and Johnson 1960) and the numbers of filled and damaged seeds per axial slice were determined. Cone crops were rated at the time of collection as nil, very light, light, moderate or heavy; the criteria for each rating were similar to those of Dobbs et al. (1976). The numbers of damaged seeds per axial slice were grouped according to crop rating in the year of cone collection (N) and in the previous year (N-1), then submitted to analysis of variance and Duncan’s New Multiple Range Test. Damage counts were also grouped by years since previous heavy or moderate crops and analyzed. Damage counts were transformed by log (x +1) prior to analysis to cor- rect for heterogeneity of variance (Sokal and Rohlf 1969). Damage by cone gall midge near Keremeos was not analyzed because of the low incidence of damage. J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 B. co/faxiana (INTERIOR ) 47 1957 60 CONE CROP RATING HEAVY MEDIUM LIGHT VERY LIGt NIL 8. col/faxiana (COAST ) DAMAGED SEEDS / AXIAL SLICE 1957 60 65 C. oregonensis (COAST ) RATING CONE CROP RATING HEAVY MEDIUM LIGHT VERY LIGt NIL CONE CROP HEAVY MEDIUM LIGHT VERY LIGt NIL Fig. 1. Cone crop rating (dashed line) and damage (solid line) by B. colfaxiana and C. oregonensis near Keremeos (interior) and Lake Cowichan (coast) from 1958 to 1982. RESULTS AND DISCUSSION Damage by Douglas-fir cone moth and Douglas- fir cone gall midge fluctuated widely from year to year at both locations (Fig. 1). Average number ( + S.E.) of damaged seeds per axial slice associated with heavy, medium, light and very light cone crops were 3.59 (+ 2.57), 3.86 (+ 2.17), 5.75 (+0.80), and 7.90 (+1.02) respectively for Douglas-fir cone moth near Keremeos; 0.13 (+ 0.06), 2.00 (+ 1.68), 1.21 (+ 0.84), and 2.08 (+ 1.23) respectively for cone moth near Lake Cowichan; and 0.21 (+0.05), 4.89 (+0.48), 2.49 (+1.04), and 2.04 (+1.17) respectively for Douglas-fir cone gall midge near Lake Cowichan. Differences in damage among categories of cone crop size in the year damage occurred (N) were not significant (P = 0.12) in either species. Contrary to our results with cone moth and cone gall midge, an inverse relationship between seed abundance and damage by the Douglas-fir seed chalcidoid, Megastigmus spermotrophus spermotrophus Wachtl (Hymenoptera: Torymidae), has been reported in Britain (Hussey 1956). Damage by Douglas-fir cone moth near Keremeos and Duglas-fir cone gall midge near Lake Cowichan increased significantly (P<0.01) with 48 J. ENTOMOL. SOc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 DAMAGED SEEDS/AXIAL SLICE (MEAN + SE) IN YEARN $ 6 4 2 n= 2 5 HEAVY MED. B. colfaxiana (INTERIOR ) 5 10 B. colfaxiana (COAST ) a C. oregonensis (COAST ) 5 7 2 LIGHT VERY NIL LIGHT CONE CROP RATING IN YEAR N-| Fig. 2. Number of seeds damaged by B. colfaxiana and C. oregonensis in relation to the size of the cone crop of the preceeding year. Bars under the same letter are not significantly (P< 0.05) different, Duncan’s multiple range test. the size of the crop the previous year (N-1) but near Lake Cowichan no relationship between cone moth damage and cone abundance the previous year could be detected (P = 0.85) (Fig. 2). Damage by cone moth near Lake Cowichan was generally light but heavy damage occurred periodically (e.g., an average of 11.5 damaged seeds per axial slice in 1973). Reasons for the periodic occurrences of heavy damage are not known. In all instances in this study, abundant crops (heavy or moderate ratings) were followed the next year by light crops or crop failures. Abundant cone crops allowed the insect populations to increase and the light crops which followed were usually heavily damaged due to the high ratio of insects to cones. Damage by both Douglas-fir cone moth near Keremeos and Douglas-fir cone gall midge near Lake Cowichan was significantly (P<0.01) higher in the year following abundant crops than in other years (Fig. 3). Others have also noted this effect (Hedlin 1964; Mattson 1980; Annila 1981). Dif- ferences in insect-caused damage among other years were not significant, although there was a tendency for damage to decrease as the period since the last abundant crop increased. These results suggest that fluctuating cone abundance limits Douglas-fir cone moth in interior areas and Douglas-fir cone gall midge in coastal areas. Similar studies on red pine, J. ENTOMOL. SOc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 12 10 w 8 wn +! qa WwW = 4 uJ Sone =] (op) q x n= 6 aq aN w tw uw 8 op) (a) wu 6 oO aq = 4 b (2) 2 = 6 HEAVY OR MED. ce) 49 B. colfaxiana (INTERIOR ) ab D 4 8 C. oregonensis (COAST ) b b 4 Té 2nd 3rd AND MORE NO. OF YEARS SINCE A HEAVY OR MEDIUM CONE CROP Fig. 3. Number of seeds damaged by B. colfaxiana and C. oregonensis in relation to the number of years since the last occurrence of a heavy or medium crop. Bars under the same letter are not significantly (P<0.05) different, Duncan’s multiple range rest. Pinus resinosa Aiton, and pinyon pines, Pinus edulis Engelm. and P. monophylla Torr. & Frem., also showed that insect-caused cone damage was limited by cone abundance the preceding year (Lester 1967; Mattson 1971; Forcella 1978, 1980). Emergence of insects from prolonged diapause can result in heavier damage than expected in some years (Hedlin 1964; Annila 1981). Induction of pro- longed diapause is inversely correlated with cone abundance the year following feeding by Douglas- fir cone moth larvae at Keremeos (Hedlin et al. 1982). No correlation between prolonged diapause and crop size was apparent for Douglas-fir cone gall midge at Lake Cowichan (Hedlin 1964). Emergence from prolonged diapause in relation to sizes of subsequent crops has not been examined in Douglas-fir cone moth or Douglas-fir cone gall midge but such emergence appears to be related to crop size in Douglas-fir seed chalcidoid (Annila 1982) and some insects attacking Norway spruce (Annila 1981). Janzen (1971) hypothesized that erratic seed pro- duction in plants has evolved in response to seed predation by animals. Such may be the case in Douglas-fir. Typically, moderate and heavy cone crops are preceded by crop failures or light crops. Sharp increases in cone production can outstrip the reproductive capabilities of the insect populations and allow for production of large quantities of seed. There are fewer crop failures and more cones are usually produced in years of light production at Keremeos than at Lake Cowichan which may ac- count for the consistntly heavier damage occurring at the former location. Damage to pine cones tends to be greatest where cone production is most consis- tent (Mattson 1971; Forcella 1980). Consistent cone production from year to year could result in loss of most seed every year due to build up of cone and seed insect populations. ACKNOWLEDGEMENTS We thank the Forest Insect and Disease Survey, Pacific Forest Research Centre, for making some of the cone collections. 50 J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 REFERENCES Annila, E. 1981. Kausen kapy-ja siementuholaisten kannanvaihtelu. Commun. Inst. For. Fenn. 101, 32 pp. Annila, E. 1982. Diapause and population fluctuations in Megastigmus specularis Walley and Megastigmus spermotrophus Wachtl (Hymenoptera, Torymidae). Ann. Ent. Fenn. 48:33-36. Dobbs, R. C., D. G. W. Edwards, J. Konishi and D. Wallinger. 1976. Guideline to collecting cones of B.C. conifers. B.C. For. Serv./Can. For. Serv. Joint Rep. No. 3, Victoria, B.C., 98 pp. Forcella, F. 1978. Irregularity of pinyon cone production and its relation to pinyon cone moth predation. Madrono 25:170-172. Forcella, F. 1980. Cone predation of pinyon cone beetle (Conopthorus edulis) production. Am. Nat. 116:594-598. Hedlin, A. F. 1960. On the life history of the Douglas-fir cone moth, Barbara colfaxiana (Kft.) (Lepidoptera: Olethreutidae), and one of its parasites, Glypta evetriae Cush. (Hymenoptera: Ichneumonidae). Can. Ent. 92:826-834. Hedlin, A. F. 1961. The life history and habits of a midge, Contarinia oregonensis Foote (Diptera: Cecidomyiidae) in Douglas-fir cones. Can. Ent. 93:952-967. Hedlin, A. F. 1964. Results of a six-year plot study on Douglas-fir cone insect population fluctuations. For. Sci. 10:124-128. Hedlin, A. F., H. O. Yates III, D. Cibrian, B. H. Ebel, T. W. Koerber and E. P. Merkel. 1980. Cone and seed insects of North American conifers. Can. For. Serv./U.S.D.A. For Serv./Secret. Agric. Recur. Hidraul., Mexico. Victoria, BC., 122 pp. Hedlin, A. F., G. E. Miller and D. S. Ruth. 1982. Induction of prolonged diapause in Barbara colfaxiana (Lepidoptera: Olethreutidae): correlations with cone crops and weather. Can. Ent. 114:465-471. Hussey, N. W. 1956. The extend of seed-loss in Douglas-fir caused by Megastigmus. Scot. For. 10:191-197. Jansen, D. H. 1971. Seed predation by animals. Ann. Rev. Ecol. Systemat. 2:465-492. Johnson, N. E., and H. J. Heikkenen. 1958. Damage to seed of Douglas-fir by the esata fir cone midge. For. Sci. 4:274-282. Lester, D. T. 1967. Variation in cone production of red pine in relation to weather. Can. J. Bot. 45:1683-1691. Mattson, W. J., Jr. 1971. Relationship between cone crop size and cone damage by insects in red pine seed production-areas. Can. Ent. 103:617-621. Mattson, W. J., Jr. 1980. Cone resources and the ecology of the red pine cone beetle, Conopthorus resinosae (Coleoptera: Scolytidae). Ann. Ent. Soc. Am. 73:390-396. Sahota, T. S., D. S. Ruth, A. Ibaraki, S. H. Farris and F. G. Peet. 1982. Diapause in the pharate adult stage of insect development. Can. Ent. 114:1179-1183. Sokal, R. R., and F. J. Rohlf. 1969. Biometry, W. H. Freeman & Co., San Francisco, 776 p. Winjum, J. K., and N. E. Johnson. 1960. A modified-knife cone cutter for Douglas-fir seed studies. J. For. 58:487-488. J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 REARING NON-DIAPAUSING WESTERN SPRUCE BUDWORM ON PRE-MIXED ARTIFICIAL DIET ROSLI MOHAMAD Department of Plant Protection Universiti Pertanian Malaysia ° Serdang, Selangor Malaysia AND PETER C. OLOFFS Department of Biological Sciences Simon Fraser University Burnaby, B.C., Canada ABSTRACT The western spruce budworm, Choristoneura occidentalis Freeman, was reared on pre-mixed artificial diet in the laboratory without diapause. The colony was maintained indefinitely with a generation time of 38 to 40 days. Females deposited an average of 307 eggs of which about 91% survived. The rearing techni- que provided a steady and reliable supply of the insects for other basic research. The supply of insects could be adjusted according to need at any particular time. Sanitation is essential to successful rearing, because contamination of diet or rearing facilities produces an unsuitable environment for the survival and develop- ol ment of newly-hatched larvae. INTRODUCTION The continuing need for basic research often calls for a large and constant supply of insects and thus for practical mass rearing techniques. Clearly, it is important to have field populations available for specific research projects, but dependence on wild populations in a seasonal climate can create pro- blems. Among these are an irregular supply of the numbers needed in the proper stages and the dif- ficult and time-consuming effort to collect them. Rearing in the laboratory circumvents these difficulties. Many insect species have been reared to order in the laboratory using artificial diet and natural food sources, especially for research on pest problems in forestry (Wellington 1949, Bergold 1951, Stehr 1954, Heron 1961). In 1965, McMorran described an artificial diet mixture which was suitable for spruce budworm. Several workers have since modified the diet and improved the rearing techni- ques as well as adapting these to the rearing of several other closely related species (Allen et al. 1968, Grisdale 1973). Still further changes in the diet and improvements on the rearing techniques by Lyon et al. (1972) and Robertson (1979), made possible the rearing of spruce budworm as diapaus- ing or diapause-free colonies. This paper reports on the rearing and perfor- mance of a non-diapausing colony of the western spruce budworm, Choristoneura occidentalis Freeman, on a pre-mixed artificial diet. The rearing was intended to provide a large and constant supply of larvae for research. MATERIALS AND METHODS Stock Colony Pupae of a non-diapausing colony were obtained originally from Dr. J. L. Robertson of the Pacific Southwest Forest and Range Experimental Station, Forest Service, Berkeley, California. Rearing Environment The rearing techniques were based on those of Lyon et al. (1972) and Robertson (1979). The larvae were reared on ready-mixed artificial diet (Table 1, Bio-Mix #9769, obtained from Bio-Serv, Inc., Fren- chtown, New Jersey) in 210-cc clear polystyrene specimen containers with fitted paper covers, the latter being pervious to water vapours (Lab-Tek Product, Division of Miles Laboratories, Inc., Naperville, Illinois). The containers allowed easy observation of the insects’ development, and prevented moisture from condensing on the con- tainer walls by allowing water loss through the cover. Moisture condensed on container walls could easily drown newly-hatched larvae, and it pro- moted fungal growth on the diet. All the rearing stages were held at 26°+1°C and 30 to 40% RH, in a room with a 16-h photoperiod, provided by two fluorescent 40-W tubes. The rear- ing containers were spaced so as to allow light to reach them easily. Preparation of Diet The diet was prepared according to instructions Sv J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 TABLE 1. Spruce Budworm Diet, BIO-MIX #9769, and Mixing Instructions as Provided by the Commer- cial Supplier*. Part Ingredient A Agar Distilled Water 2k B Casein Fiber Wesson Salt Mix Toasted Wheat Germ Methyl Parahydroxybenzoate Aureomycin Aseorbie Acid Choline Chloride sucrose Linseed Oil KK C Vitamin Mixture #722 * D 4M KOH Solution Formaldehyde Mixing Instructions for 1 1 of Diet. 1, Add 25.3 ¢ of Part A (agar) to 835 ml of water. “ok While stirring agar solution constantly, bring to a full boil Lord. min: oe Transfer agar solution to blender. Cool to 65C to 70C, add 135.2 g¢ of Part B, 10-¢ of Part C, and 5.6 ml of Parn: 4. Blend for 1 minute or until mixed thoroughly. ap Dispense immediately. BIO-SERV, Ine., Frenchtown, New Jersey. a Premixed by supplier. J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 53 from the suppliers (Table 1), and poured im- mediately into 150 x 25 mm sterilized plastic Petri- dishes, to a depth of about 2 cm, and allowed to cool and set. After 1 to 2h, the diet gel was cut into cubes of about 2 x 2 x 2 cm. Each rearing cup was half-filled with these cubes. If the diet was not used immediately, it was kept uncut in the Petri-dishes at 4°C for up to two weeks. Propagation of Colony Pupae and Adults. Pupae were collected from the rearing cups about twice weekly and sexed accor- ding to the number of abdominal segments visible on the venter as described by Robertson (1979). The pupae were then placed in brown paper bags of about 20 x 23 x 39 cm with six strips of Scotch wax paper loosely tossed in, each strip 2 to 4 cm wide and 30 cm long. The wax paper provided the newly emerged moths with a support they could grasp during mating and oviposition. Fifty male and 50 female pupae were placed in each bag and held on shelves in the described rearing room. Eggs. After 7 to 10 days, depending on the age of the pupae collected, the bags were opened and strips of wax paper with egg masses adhering to them were collected. The adult moths were transferred to new bags, prepared as before, for another oviposition. The eggs were collected from these new bags after three days. The procedure was repeated for one more time before the adults were disposed of by deep freezing at -12°C. The strips of wax paper were cut into pieces to separate each egg mass. The eggs and the pieces of paper to which TABLE 2. Development Time for Non-Diapausing Colony of Western Spruce Budworm, C. occidentalis. nee UBC. C.N-G. Det. : Dondale Steatoda americana (Emerton). Victoria S.L 2 MEG. Det. : Emerton, Levi Steatoda borealis (Hentz). Prince George, Balfour, Kamloops, Salmon Arm, Fort St. John Sb. CNC. BG. E ew Det. : Dondale, Leech Steatoda grossa Chamberlin and Ivie. Victoria, Saanich, Vancouver, Comox, Nanoose Bay, Shaugnessy (Vancouver), Summerland, Langford Sa 2. UVIGC.. UB. C2 B/C PMs CNG: Det. : Dondale Steatoda hespera Chamberlin and Ivie. Salmon Arm, Kamloops, Prince George, Vernon, Nicola, Summerland, Penticton, Manning Park S.L. ~ U.B.C.. B.C.P.M.oGC.IN-C. Det. : Dondale, Leech, Levi Robertus vigerens (Chamberlin and _ Ivie). Cassiope Lake (Brooks Peninsula), Shuswap Falls, Courtenay, Mission City, Revelstoke, Brooks Peninsula S.E. 2°.B:G7P M3 GN.G, Det. : Dondale J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 FAMILY LINYPHIIDAE Centromerus sp. Terrace. Helsdingen (1973, Figs 25, 26) S.L. : M.C.Z. Det. : Helsdingen Drapetisca alteranda Chamberlin. Vancouver, Lake Cowichan S.L. : Bragg, C.N.C. Det. : Leech, Dondale Frontinella pyramitela (Walckenaer). Jackfish Creek, Creston, Summit Lake (Alaska Highway), Vernon S2L. =) B:C.P.M.,C.N.C: Det. : Dondale Pimoa altioculata (Keyserling). Kyuquot, Metlakatla, Departure Bay, Nanaimo, Sidney, Port Alberni, Victoria, Nanoose Bay, Langford, Horne Lake, Parksville So, 2 U. VIC.; “B30. PoMe, 7G. N2 Ce. A.M.N.H. Det. : Dondale, Gertsch, Chamberlin, Ivie Pityohyphantes cristatus (Chamberlin and Ivie). Cottonwood River, Stoner, Summerland, Mount McLean, Apex Mountain (Keremeos) S.L. : B:C.P.M., C.N.C., U.B.C. Det. : Dondale Pityohyphantes limitaneus (Keyserling). Atlin S$... + “C.N.C. Det. : Dondale Pityohyphantes vancouveranus Chamberlin and Ivie. Cameron Lake S.L. : A.M.N.H. Det. : Chamberlin, Ivie Neriene digna (Keyserling). Victoria, Kyuquot, Princeton, Union Island, Vancouver, Langford Slee UL VIC../B GIP: Ma C:N.C. Det. : Dondale, Gertsch Neriene litigiosa (Keyserling). Victoria, Cowichan Lake, Departure Bay, Vernon, Saanich, Lillooet S:L. + U.VIC., BC.P.M...C:.N:C. Det. : Dondale Neriene radiata (Walckenaer). Paul Lake, Trinity Valley, Lillooet, Creston, Salmon Arm S.L. + U.B:G.2 B.G.P. Me. C.N-C.._K.B:S. Det. : Dondale, Leech Microlinyphia dana Chamberlin and _Ivie. Sooke, Victoria, Anthony Island, Queen Charlotte Island, Ladysmith, Doom Moun- tain (Brooks Peninsula), Kyuquot, Osoyoos, Hotsprings Island, Errington, Wellington, Goldstream Park, Squamish S.L. ¢ U.B.C., C.N-G:, B.C .P.M:,U: VIC. Det. : Dondale, Gertsch, Helsdingen Microlinyphia mandibulata punctata (Chamberlin and Ivie). Jackfish Creek, Stoner, Pouce Coupe, Dawson Creek, Jaf- fray, Cranbrook, Liard River Hotsprings, Vernon S.L. : C.N.C., B.C.P.M. Det. : Dondale Estrandia grandaeva (Keyserling). Liard River Hotsprings, Summit Lake S.L. ¢ U.B.C.>¢.N.C: Det. : Dondale Helophora reducta (Keyserling). Masset, Metlakatla, Terrace, Vernon, Penticton, Vancouver S.L. : C.N.C., Charles Det. : Dondale Lepthyphantes alaskanus (Banks). Cassiope Lake (Brooks Peninsula) Sala. 1 -C.N.G: Det. : Dondale Lepthyphantes arboreus (Emerton). Glacier Na- tional Park Silie. f° CNG. Det. : Dondale Lepthyphantes complicatus (Emerton). Terrace S.L. $ M.C.Z. Det. : Zorsch Lepthyphantes fructuosus (Keyserling). Vancouver S.L. : B.M. Det. : Zorsch Lepthyphantes leprosus (Ohlert). Summerland S.L. : C.N.C., Charles Det. : Dondale Lepthyphantes nebulosus (Sunderall). Kamloops SLs sik Rss: Det. : Leech Lepthyphantes sammamish Levi and Levi. Queen Charlotte Islands Si be GN. GC: Det. : Dondale Lepthyphantes tenuis (Blackwall). Cape Cook Lagoon (Brooks Peninsula), Comox, Sumas, Vernon, Summerland, Vancouver, Vaseux Lake S42 C:N.C. Det. : Dondale Lepthyphantes_ turbatrix (O.P.-Cambridge). Summit Lake (Alaska Highway) Silas. eo. GaN. Ce! Det. : Dondale Lepthyphantes zebra (Emerton). Aleza Lake, Terrace SL] M:G.Z. Det. : Zorsch Lepthyphantes poss. zelata Zorsch. Cape Cook Lagoon (Brooks Peninsula) S.L. ; -G.N.C.,.B.C.P-M: Det. : Redner Bathyphantes alameda Ivie. Kyuquot S.L. : A.M.N.H. Det. : Ivie Bathyphantes alascensis (Banks). Cape Cook Lagoon (Brooks Peninsula), Kyuquot, Tofino, Wellington Sel. = C.N.C., A.M.N.H. Det. : Dondale, Ivie Bathyphantes brevipes (Emerton). Metlakatla, Mount Benson, Parksville, Wellington, Masset S.L. : A.M.N.H., C.N.C. Det. : Ivie, Dondale Bathyphantes concolor (Wider). Vernon, Sum- merland, Richmond Salon ALMUN ad C.N.G. Det. : Ivie, Dondale Bathyphantes keeni (Emerton). Metlakatla, Kyuquot, Doom Mountain (Brooks Penin- sula), Tofino, Wellington, Prince Rupert, Queen Charlotte Islands S.L. : B.C.P.M., C.N.C., A.M.N.H. Det. : Dondale, Ivie Bathyphantes magnificus Chamberlin and Ivie. Cameron Lake, Terrace S.L. : A.M.N.H. Det. : Ivie Bathyphantes malkini Ivie. Wellington Olay ah MINE Det. : Ivie Bathyphantes orica Ivie. Wellington S.L. : A.M.N.H. Det. : Ivie Bathyphantes pallidus (Banks). Penticton, Kelowna, Vernon, Terrace, Summit Lake (Alaska Highway) S.L. : A.M.N.H., C.N.C. Det. : Ivie, Dondale Bathyphantes waneta Ivie. “Nelson”, Ivie’s map shows Victoria and Glacier National Park S.L. : C.N.C., R.O.M. Det. : Ivie, Dondale Linyphantes orcinus (Emerton). Inverness 5.L. : M.C.Z. Det. : Helsdingen Linyphantes pualla Chamberlin and _Ivie. Sidney S.L. : A.M.N.H. Det. : Chamberlin, Ivie Linyphantes victoria Chamberlin and _Ivie. Victoria S.L. : A.M.N.H. Det. : Chamberlin, Ivie Arcuphantes arcuatus (Keyserling). Parksville S:L.. : A:M.N.H. Det. : Chamberlin, Ivie Centromerita bicolor (O.P.-Cambridge). Bur- naby Mountain Sales (CIN: G, Det. : Dondale Wubana atypica Chamberlin and _Ivie. Cameron Lake S.L. : A.M.N.H. Det. : Chamberlin, Ivie J. ENTOMOL. SOc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 85 \ Wubana pacifica (Banks). Goldstream Park, Cameron Lake S'L:.. 2 “Bi@.P-M...G.N.G. Det. : Dondale, Chamberlin, Ivie, Redner FAMILY ERIGONIDAE Ceraticelus atriceps (O.P.-Cambridge). Field, Atlin, Mount Revelstoke, Comox SD. JO NC.ULB.G. Det. : Dondale, Redner Ceraticelus fissiceps (O.P.-Cambridge). Mount Revelstoke National Park, Hope Sale = /C.N,G Det. : Redner Ceraticelus vesperus Chamberlin and_ Ivie. Lillooet, Hope Ss 3. (CNiG. Det. : Dondale, Redner Ceraticelus silus Dondale. Vancouver S.L.. 2-GiN.G, Det. : Dondale, Redner Ceratinella brunnea Emerton. Liard Hotspr- ings, Tetsa River Sli uN, Det. : Dondale, Redner Ceratinops inflatus (Emerton). Cape Cook Lagoon (Brooks Peninsula), Trinity Valley, Manning Park, Goldstream Park, Silverton S.lo2 = CNC, Det. : Redner Collinsia ksenia (Crosby and Bishop). Kelsall Lake, Kyuquot, Summerland, Terrace, Yoho National Park, Salmon Arm, Revelstoke S;L,.2 -B.G.P.M2GiN.G; Det. : Dondale, Gertsch, Redner Collinsia plumosa (Emerton). Comox S-le - EN.C. Det. : Redner Collinsia stylifer Chamberlin). Clinton, Jordan River, Sooke Sele 7 GrNGG, Det. : Redner Collinsia wilberi Levi and Levi. Manning Park SL: 2 G.N.G. Det. : Redner Diplocentria bidentata (Emerton). Sikanni Chief River, Whiskers Point Provincial Park, Tetsa River, Fort St. John, Liard River Hotsprings, Summit Lake (Alaska Highway) Sly 2 CNG, Det. : Redner, Millidge Diplocentria perplexa (Chamberlin and Ivie). Sikanni Chief River, Manning Park Sel. 3° @N.C: Det. : Millidge Diplocentria rectangulata (Emerton). Sikanni Chief River, Summit Lake (Alaska Highway), Tetsa River 9. 16.- 3) CNC: J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 Det. : Millidge Dismodicus alticeps Chamberlin and Ivie. Liard River Hotsprings, Atlin Sb. CLN.G, Det. : Redner Dismodicus bifrons decemoculatus (Emerton). Terrace SL aeeeN.C, Det. : Dondale, Redner Enidia marxi (Keyserling). Nanaimo, Sidney, Summit Lake (Alaska Highway) Dele. 0G 2N.C. Det. : Redner Entelecara erecta (Emerton). Courtenay, Man- ning Park, Heather Mountain Brun 2 "CNG, Det. : Redner Entelecara media (Kulczynski). Burnaby, Atlin, Lillooet SS laee CANCC. Det. : Redner Eperigone trilobata (Emerton). Terrace, Yoho National Park, Comox Sil. 2 -G.N.G; Det. : Dondale, Redner Erigone aletris Crosby and Bishop. Comox, Vancouver, Hope Sle oe GING, Det. : Redner Erigone paradisicola. Crosby and_ Bishop. Glacier National Park S LiaeJG.N.C. Det. : Dondale Gnathonarium famelicum Crosby and Bishop. Mile 379 Alaska Highway, Lakelse Hotspr- ings, Fernie, Kamloops, Pine Pass, Hazelton, Prince George (100 km east), McBride S932 CNG. Det. : Redner, Dondale Gonatium crassipalpum Bryant. Sikanni Chief River Sea N. Ca Det. : Redner, Dondale Hilaira herniosa (Thorell). Sikanni Chief River, Tetsa River Sis eG N.C, Det. : Redner Horcotes quadricristatus (Emerton). Summit Lake (Alaska Highway) SL. : -C.N.C; Det. : Redner Hypselistes florens (O.P.-Cambridge). Hyland River, Hosmer, Mackenzie, Dawson Creek, Liard River, Liard Hotsprings, Lemoray, Cottonwood River, Prince Rupert, Charlie Lake, Sikanni Chief River Sic, ¢- CN... BiG P.M. Det. : Dondale, Redner Islandiana falsifica (Keyserling). Summit Lake (Alaska Highway) Sob. 2 “CNG, Det. : Redner Islandiana flaveola (Emerton). Terrace SL. 3-C.N.G. Det. : Redner Maso sundevalli (Westring). Liard Hotsprings S.L. 7 CNC, Det. : Redner Minyriolus pampia Chamberlin. Sikanni Chief River S.-C NG: Det. : Redner Oedothorax trilobatus (Banks). Revelstoke, Liard Hotsprings S.L. + C.N.C, Det. : Redner Pelecopsis sculptum (Emerton). Metlakatla, Revelstoke, Errington S:Le* €.N.C..7U-B-C: Det. : Redner Pocadicnemis pumila (Blackwall). Frederick Island (Queen Charlotte Islands), Fulford Harbour, Summerland, Manning Park, Cowichan Lake, Honeymoon Bay SiLines (GNC: Det. : Redner Rhaebothorax paetulus (O.P.-Cambridge). Summit Lake (Alaska Highway) San GIN GC: Det. : Redner Sciastes truncatus (Emerton). Sikanni Chief River, Summit Lake (Alaska Highway) SL. @ CLN-G. Det. : Redner Scironis sima Chamberlin. Goldstream Park, Sidney, Mesachie Lake, Cowichan Lake, Barkley Sound S.L. * B.C:P.M., €.N.C. Det. : Dondale, Redner Scironis tarsalis (Emerton). Liard Hotsprings Se 2 CNG. Det. : Redner Scotinotylus alpinus (Banks). Summit Lake (Alaska Highway), Pink Mountain, Chilkat Pass SL. 2 GN.G Det. : Millidge Scotinotylus ambiguus Millidge. Millidge 1981, Map 3 S.L. : A.M.N.H. Det. : Millidge Scotinotylus bicavatus Millidge. Manning Park Slee eUNG: Det. : Millidge Scotinotylus bicornis (Emerton). Terrace Sila vy MLC.Z, Det. : Millidge Scotinotylus eutypus (Chamberlin). Parksville, Sidney S.L. : A.M.N.H. Det. : Millidge Scotinotylus monoceros (Simon). Burnaby, Ter- race, Manning Park, Mount Needham (Queen Charlotte Islands), Vancouver S.L. : C.N.C. Det. : Millidge Scotinotylus patellatus (Emerton). Goldstream Park, Metlakatla, Manning Park, Queen Charlotte Islands, Honeymoon Bay Sus ¢ BG lP.M. G.N:G. Det. : Dondale, Redner, Millidge Scotinotylus protervus (L. Koch). Summit Lake (Alaska Highway) Sale CNC: Det. : Millidge Scotinotylus sacer (Crosby). Manning Park, Summit Lake (Alaska Highway), Sikanni Chief River Solan ey CaN Ge: Det. : Millidge Scotinotylus sanctus (Crosby). Kamloops Se “GIN.G, Det. : Millidge Sisicottus montanus (Emerton). Whiskers Point Park, Sikanni Chief River, Liard River Hotsprings, Summit Lake (Alaska Highway), Goldstream Park 5 Ua. GNC. Det. : Redner Sisicottus orites (Chamberlin). Manning Park, Clinton, Trinity Valley, Burnaby, Terrace, Courtenay, Cowichan Lake, Mesachie Lake, Goldstream Park, Cayuse, Prince George Srlé. 7 GC. N.e, Det. : Dondale, Redner Sisicus apertus (Holm). (senior synonym of S. longitarsi Chamberlin and Ivie, according to Holm, 1950). Radium Sel. 2. (C.NEC: Det. : Redner, Dondale Sisicus penifusiferus Bishop and Crosby. Burton, Goldstream Park Sols, 2) (CRN. Det. : Redner Sisis rotundus (Emerton). Summit Lake (Alaska Highway), Sikanni Chief River Sulla 6) sOaNGG. Det. : Redner Soucron arenarium (Emerton). Springhouse pels. = CNG: Det. : Redner Sougambus bostoniensis (Emerton). Penticton S.L. C.N.C. Det. : Dondale, Redner Spirembolus demonologicus (Crosby, in Chamberlin). Saanich Sula 2 OG IN-G: Det. : Millidge J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 87 Spirembolus prominens Millidge. Summerland, Manning Park, Victoria Sis = GNC. Det. : Redner “Spirembolus vasingtonus Chamberlin”. See Millidge (1980). Kyuquot S.L 2 G.N.G. Det. : Gertsch Symmigma minimum (Emerton). Golden, Barkley Sound, Newcombe Harbour, Mann- ing Park, Silverton S.Ee2 CINAG. Det. : Redner Tachygyna haydeni Chamberlin and Ivie. Sum- mit Lake (Alaska Highway), Manning Park Sola, wee NEG: Det. : Redner, Millidge Tachygyna sima Chamberlin. Sidney S.L. : A.M.N.H. Det. : Chamberlin, Ivie Tachygyna ursina (Bishop and Crosby). Mann- ing Park, Vancouver, Goldstream Park S.1G.2.) CNG, Det. : Redner, Millidge Tachygyna_ vancouverana (Chamberlin and Ivie). Cassiope Lake (Brooks Peninsula), Trinity Valley, Goldstream Park, Manning Park, Saanich, Mesachie Lake, Princeton, Terrace See / GNC: Det. : Dondale, Redner, Millidge Tapinocyba minuta (Emerton). Goldstream Park Sb GANG: Det. : Dondale, Redner Tiso vagans (Blackwall). Burnaby Sb GN.G, Det. : Dondale Tunagyna debilis (Banks). Prince George, Liard River Hotsprings, Sikanni Chief River, Sum- mit Lake (Alaska Highway) See eC NEG: Det. : Millidge Walckenaeria atrotibialis O.P.-Cambridge. Burnaby, Mesachie Lake, Liard Hotsprings, Clinton, Honeymoon Bay, Terrace Sib 2 GANG: Det. : Millidge, Redner Walckenaeria auranticeps (Emerton). Van- couver Island S.L. : A.M.N.H. Det. : Millidge Walckenaeria castanea (Emerton). Liard Hotsprings, Prince George (100 km east) S.L. > C.N.G, Det. : Dondale, Redner Walckenaeria directa (O.P.-Cambridge). Ter- race, Manning Park Bee CNG) Det. : Millidge J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), Dec. 31, 1984 Walckenaeria exigua Millidge. Terrace, Mount St. Paul, Manning Park S:L.o% -€.N.C, Det. : Millidge Walckenaeria pellax Millidge. Manning Park Seba. GN: C. Det. : Millidge Walckenaeria septentrionalis Millidge. Sidney S.L. : A.M.N.H. Det. : Millidge Walckenaeria subspiralis Millidge. Osoyoos, (plus 3 additional localities in Map 2 of Millidge 1983) Sse eCUNGG, Det. : Millidge Zornella cultrigera (L. Koch). Tetsa River, Sikanni Chief River, Summit Lake (Alaska Highway) Sle GANG, Det. : Redner Zygottus corvallis (Chamberlin). Cape Cook Lagoon (Brooks Peninsula), Burnaby, Goldstream Park, Mesachie Lake S.Le = CNC: Det. : Redner FAMILY ARANEIDAE Metellina curtisi (McCook). Victoria, Ladysmith, Sooke, Kyuquot, Langford, Doom Mountain (Brooks Peninsula) Depar- ture Bay, Orchard Point Beach (Brooks Peninsula), Nanaimo, Vancouver, Hope, Squamish 5 Lows ¢U VIC CBCP MM. CNG, Det. : Dondale, Gertsch, Levi Metellina mimetoides Chamberlin and Ivie. Vernon S.L. : Charles, C.N.C. Det. : Dondale Metellina segmentata (Clerck) (introduced from Europe). Vancouver, Surrey S.L. : M.C.Z., C.N.C., Bragg , Leech Det. : Levi, Dondale Argiope trifasciata (Forskal). Prospect Lake, Penticton, Osoyoos, Victoria, Kamloops, Nanaimo, Oliver, Goldstream Park, Vaseux Lake 5.0) 2) UVIC 2 B.C.PM. CNC. UBC. Det. : Redner, Dondale, Levi Metepeira foxi Gertsch and Ivie. Osoyoos, Kamloops, Lillooet, Cache Creek, Savona, Pritchard, Walhachin, Lytton, Oliver S.L. : B.C.P.M., C.N.C. Det. : Dondale, Levi Metepeira grandiosa alpina Chamberlin and Ivie. Falkland 8 ,92)-C.N.C. Det. : Levi Metepeira grandiosa grandiosa Chamberlin and Ivie. Prince George Sob et Det. : Levi Metepeira grandiosa palustris Chamberlin and Ivie. Atlin, one additional locality in Map 2 of Levi (1977) SL. « C.N.C. Det. : Levi Cyclosa conica (Pallas). Creston, Vancouver, Hope, Victoria, Cowichan Lake, Trinity Valley S.L. ; U.B.C., U.VIC., C.N.C., B.C.P,M. Det. : Dondale, Levi Neoscona arabesca (Walckenaer). Cranbrook, Wardner, Errington, Prince George (East of) S.L. : B.C.P.M., C.N.C. Det. : Dondale, Levi Neoscona pratensis (Hertz). Terrace S.L. + M.C.Z, Det. : Berman, Levi Zygiella atrica (C. L. Koch). Victoria, Vancouver S.L. : B.C.P.M., C.N.C. Det. : Levi, Gertsch Zygiella dispar (Kulcezynski). Victoria, Metlakatla, Kyuquot, Terrace, Ocean Falls, Wellington, Mount Benson, South Pender Island S.L. : U.VIC., B.C.P.M. Det. : Dondale, Levi, Gertsch Zygiella x-notata (Clerck). Victoria, Langford, Metlakatla, Vancouver, Wellington, Sooke, North Pender Island S.L. : U.VIC., B.C.P.M., C.N.C. Det. : Dondale, Levi Singa keyserlingi McCook. Pouce Coupe S75. C.PiM: Det. : Dondale, Levi Araniella displicata (Hentz). Anthony Island, Spuzzum, Vernon, Osoyoos, Cherryville, Tofino, Manning Park, Vancouver, Kyu- quot, Pleasant Camp, Trinity Valley, Kamloops, Garibaldi Park S.L. : U.B.C., U.VIC., B.C.P.M., C.N.C. Det. : Dondale, Gertsch, Levi Nuctenea patagiata (Clerck). Manning Park, Kyuquot, Victoria, Nelson, Vancouver, Metlakatla, Sproat Lake, Kamloops, Salmon Arm, Fletcher Lake, Vernon, Penticton, Prince George, Langford, Mitlenatch Island, Cowichan Lake, Stoner, Oliver, Mackenzie, Summerland, Hope, Sooke, Meziadin Junc- tion (Hwy. 39-90 kms south of) S.L. : U.B.C., U.VIC., B.C.P.M., C.N.C. Det. : Dondale, Levi, Gertsch Nuctenea sclopetaria (Clerck). Nelson, Okanagan Landing, Manning Park, Mesachie Lake S.L. : B.C.P.M., C.N.C. Det. : Dondale J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), Dec. 31, 1984 Nuctenea cornuta (Clerck). Atlin Slo ae CAN. Det. : Levi Araneus corticarius (Emerton). Vernon S.L. : Charles Det. : Dondale Araneus diadematus Clerck. Victoria, Langford, Sooke, Prospect Lake, Van- couver, Manning Park, Metchosin, Duncan, Courtenay, Galiano Island Si. @) B.G:P.M. U.VIG.. "U-B.C., C.N.C. Det. : Dondale, Levi Araneus gemma (McCook). See Map 8 in Levi (1977) Stlbeas ir. Det. : Levi Araneus gemmoides Chamberlin and _ Ivie. South Pender Island, Victoria, Kyuquot, Tranquille, Wardner, Vernon, Kamloops, Salmon Arm, Penticton, Departure Bay, Errington Sela (BD G-P.M.s-U.B-C.. C.N.G. Det. : Dondale, Gertsch, Levi Araneus iviei (Archer). Prince George S: Lewsey C.N-G, Det. : Dondale Araneus marmoreus Clerck. Manning Park, Creston, Vancouver, Hope, Kamloops, Mons Lake, Prince George S.b:. ¢.-B.G)P.M..-C.N.G. Det. : Dondale, Levi Araneus nordmanni (Thorell). Kyuquot, Well- ington, Manning Park, Ross Lake, Victoria, Langford, Stewart Island, Trinity Valley ».L.°; U.B-C., U,VIC., B.C.P.M., C.N.C. Det. : Dondale, Gertsch, Levi Araneus saevus (C. L. Koch). Merritt, Trinity Valley, Wells Grey Park, Victoria, Kyuquot, Salmon Arm, Hope, Glacier, Vancouver, Creston, Atlin S.C > U-B.G..8,C.P:M., C.N-C, Det. : Dondale, Levi Araneus trifolium (Hentz). Langford, Victoria, Saanich, Kyuquot, Sooke, Lake Cowichan, Comox, Kalmia Lake, Salmon Arm, Cape Scott, Redonda Bay Salas ULVIC,, BIC PM,“C.N.C, Det. : Dondale, Levi Aculepeira carbonarioides (Keyserling). Kamloops, Mount St. Paul, Pink Mountain S.0..; B.C.P.M..C.N.C: Det. : Levi Aculepeira packardi (Thorell). Summit Lake (Alaska Highway), Rock Creek, Atlin, Pen- ticton, Moose Horn Lake, Ketchum Lake, Vernon, Kamloops, Victoria 5.L. : C.N.C., M.C.Z. Det. : Levi Hypsosinga alberta Levi. Summit Lake (Alaska Highway) 89 Scie SOCAN. Det. : Levi Hypsosinga groenlandica Simon. Apex Moun- tain (Keremeos) SL. + -G.N.C, Det. : Dondale Hypsosinga pygmaea (Sunderall). Queen Charlotte Islands, Okanagan Falls, Kamloops, Summerland Silie = 4OUNGG: Det. : Dondale FAMILY TETRAGNATHIDAE Pachygnatha clercki Sundevall. Springhouse S:be 2 G.NG, Det. : Levi Pachygnatha dorothea McCook. near Victoria Sula, 7 Det. : Levi Tetragnatha caudata Emerton. Creston, Port Alberni, Windermere, Chilcotin S.L. : B.C.P.M., C.N.C. Det. : Dondale, Levi Tetragnatha dearmata Thorell. Summit Lake (Alaska Highway) Se. 2 CO NEG: Det. : Levi Tetragnatha elongata Walckenaer. Salmon Arm, Wellington S.L. 4 Bi C.F.M. Det. : Levi Tetragnatha extensa (Linnaeus). Jackfish Creek, Creston, Fort. St. John, Brasenia Pond (Brooks Peninsula), Dunster, Summit Lake (Alaska Highway), Chilcotin, King Salmon Lake, Fort Nelson S.L. -2 .B-C.P.M,, €.N.C; Det. : Dondale, Levi Tetragnatha laboriosa Hentz. Manning Park, Triangle Island, Kyuquot, Jaffray, Windermere, Corbin, Spuzzum, Cranbrook, Victoria, Creston, Lemoray, Amos Creek (Brooks Peninsula), Cassiope Lake (Brooks Peninsula), Kamloops, Vernon, Prince George S.L. : U.VIC., U.B.C., B.C:.P.M., C.N.C. Det. : Dondale, Levi, Gertsch, Kurata Tetragnatha shoshone Levi. Victoria Sy Det. : Levi Tetragnatha versicolor Walckenaer. Salmon Arm, Penticton, Kyuquot, Union Island, Osoyoos, Cranbrook, McIntyre Lake, Liard River Hotsprings, Nelson, Spuzzum, Vic- toria, Canim Lake, Kamloops, Tsusiat Falls, Errington, Anarchist Mountain, Metlakatla, Lower Post, Terrace, Comox, Cowichan Lake, Pritchard, Fort Nelson, Manning Park, Summit Lake (Alaska Highway), Revelstoke National Park S-ba.> -BiG.P.MU.VIC..'G.N.G. Det. : Dondale, Levi, Gertsch J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 FAMILY AGELENIDAE Cybaeus eutypus Chamberlin and Ivie. Sooke, Ladysmith, Cape Cook Lagoon (Brooks Peninsula), Goldstream Park, Cultus Lake Park 5.0. ¢.B;C.P.M., C.N.G; Det. : Dondale Cybaeus morosus Simon. Cape Cook Lagoon (Brooks Peninsula), Sproat Lake, Queen Charlotte Islands, Terrace, Lillooet, Squamish S.L. : B.C.P.M., C.N.C. Det. : Dondale, Gertsch Cybaeus reticulatus Simon. Victoria, Kyuquot, Cape Cook (Brooks Peninsula), Metlakatla, Agassiz, Terrace, Campbell River, Point Warde, Goldstream Park S.L. : B.C.P.M., C.N.C. Det. : Dondale, Gertsch Cybaeus signifer Simon. Langford, Cowichan Lake, Victoria, Kyuquot S.L. : U.VIC., B.C.P.M. Det. : Dondale, Gertsch, Chamberlin, Ivie Cybaeina minuta (Banks). Victoria, Kyuquot S.L. : B.C.P.M. Det. : Gertsch Cybaeota nana Chamberlin and Ivie. Victoria (20 miles north of) S.L. : A.M.N.H. Det. : Chamberlin, Ivie Cybaeota vancouverana Chamberlin and Ivie. Kyuquot, Sidney Se 27 8,.CiP.M, Det. : Gertsch, Chamberlin, Ivie Cryphoeca peckhami Simon. Cassiope Lake (Brooks Peninsula), Kyuquot, Vancouver S.L. : B.C.P.M., C.N.C Det. : Dondale Cicurina idahoana Chamberlin. Penticton, Lillooet S.L. : C.N.C., A.M.N.H. Det. : Dondale, Chamberlin, Ivie Cicurina intermedia Chamberlin and _ Ivie. Vaseux Lake S: Le. ¢)°B:C.P-M3-G.N:G. Det. : Dondale Cicurina simplex Simon. Departure Bay, Cameron Lake, Sidney S.L. : A.M.N.H. Det. : Chamberlin, Ivie Cicurina tersa Simon. Campbell River, Depar- ture Bay, Sidney S.L. : A.M.N.H. Det. : Chamberlin, Ivie, Exline-Frizzell Agelenopsis actuosa (Gertsch and Ivie). Goldstream Park, Sidney, Saanich Inlet S.L. : B.C.P.M., A.M.N.H. Det. : Chamberlin, Ivie Agelenopsis oklahoma (Gertsch). Oliver S:bs @ “CANCG, Det. : Dondale Agelenopsis oregonensis Chamberlin and Ivie. Cowichan Lake, Summerland, Saanich Inlet (West side of) S.L. + U.VIC.,C.NIG. Det. : Dondale, Chamberlin, Ivie Agelenopsis potteri (Blackwall). Osoyoos, Oliver, Vernon, Kamloops, Salmon Arm, Langford, Lillooet, Summerland, Cowichan, Seton Creek, Vancouver S.L. : U.VIC., B.C.P.M:,-GC.N.©: Det. : Dondale Agelenopsis utahana (Chamberlin and Ivie). Salmon Arm, Lillooet, Canoe S.Le = B.C{P.M.,'C.N.G. Det. : Leech, Dondale Tegenaria agrestis (Walckenaer). Vancouver, Victoria, Goldstream Park, Summerland S.L. : U.B.C., B.C.P.M., G.N.G: Det. : Dondale Tegenaria domestica (Clerck). Victoria, Galiano Island, Departure Bay, Kamloops, Summerland, Mesachie Lake, Kyuquot S.L;°:¢ U.B.C;, B-G!P.M., CIn:C. Det. : Dondale, Leech, Chamberlin, Gertsch Tegenaria duellica Simon (=T. gigantea Chamberlin and Ivie). See Brignoli (1978). Victoria, Courtenay, Vancouver, Nanoose Bay, Alert Bay, Nanaimo, Campbell River, Sidney, Oak Bay, Langford, Weir Beach, Lillooet, Mitlenatch Island, Galiano Island, Wellington S.L. : C.N.C., U.VIC., U.B.C., B.C.P.M. Det. : Dondale, Chamberlin Calymmaria emertoni (Simon). Kyuquot, Departure Bay, Goldstream Park SL... Bic. PMs CN. @ Det. : Gertsch, Heiss Blabomma grandis Chamberlin and Ivie. Sidney (type locality) S.L. : A.M.N.H. Det. : Chamberlin, Ivie Dirksia cinctipes (Banks). Kyuquot, Vancouver, Cape Cook Lagoon (Brooks Peninsula) S.L. : B.C.P.M., C.N.C. Det. : Gertsch, Dondale FAMILY HAHNIIDAE Antistea brunnea (Emerton). Near Prince Rupert S.L. : No location, M.C.Z.(?) Det. : Opell, Beatty Neoantistea agilis (Keyserling). Manson River, Prince Rupert, Fort St. John S.L. : No location Det. : Opell, Beatty Neoantistea magna (Keyserling). Mosquito Lake (Queen Charlotte Islands), Osoyoos S.L4 2'G.N. G2, "(2) Det. : Opell, Beatty Hahnia cinerea Emerton. Vancouver, Kamloops, Prince Rupert Sil) M-G.Z. Det. : Opell, Beatty Hahnia glacialis Soerensen. Lakelse Lake Sti. ': CNG. Det. : Dondale Hahnia ononidum Simon. Atlin Sale @ (CONG. Det. : Opell, Beatty FAMILY MIMETIDAE Mimetus hesperus Chamberlin. Walhachin SL): -G.N.C, Det. : Dondale FAMILY PISAURIDAE Dolomedes triton (Walchenaer). Liard River Hotsprings, Victoria, Riske Creek, Summit Lake (Alaska Highway), Meldrum Creek, Cariboo Sb. ¢. BC. P.M. CNC. Det. : Dondale FAMILY LYCOSIDAE Pirata bryantae Kurata. Tetsa River, Sikanni Chief River Sib” C.N.C, Det. : Dondale, Redner Pirata insularis Emerton. Liard River Hotspr- ings, Burnaby SsL: > CiN.C: Det. : Dondale, Redner Pirata piraticus (Clerck). Kyuquot, Cape Cook Lagoon (Brooks Peninsula), Stoner, Cariboo, Kamloops, Comox, Pacific Rim National Park, Toebiter Bog (Brooks Peninsula), Bur- naby, Oliver, Goldstream Park Goldstream Park S73 ¢. Be. PM, G.N.C. Det. : Dondale, Redner Alopecosa aculeata (Clerck). Sparwood, Spr- inghouse, Summerland, Summit Lake (Alaska Highway), Fort Nelson, Tetsa River, Sikanni Chief River, McBride, Fort St. John, Manning Park, Lower Post, Atlin, Yoho, Salmon Arm, Lillooet, Terrace, Tutshi River, Chilkat Pass Sun a WaVIC.. B-C2PIM.. CNC, Det. : Dondale, Redner Alopecosa kochi (Keyserling). Weir Beach, Nanoose Bay, Victoria, Errington, South Pender Island, Departure Bay, Goldstream, Saanich, Summerland, Hope, Comox, Ver- non, Grand Forks, Golden, Mandarte Island, Kelowna Sole tb. PM, ULB, G.-C .N.G, Det. : Dondale, Redner Alopecosa pictilis (Emerton). Summit Lake (Alaska Highway) Sal 7 SCN. Det.: : Dondale, Redner J. ENTOMOL. Soc. Brit. COLUMBIA 81 (1984), Dec. 31, 1984 9] Trochosa terricola Thorell. Sable Island, Bowen Island, Celista, Kamloops, Penticton, Cape Cook (Headlands), Comox, Metlakatla, Lillooet, Salmon Arm, Telkwa, Sproat Lake, Fort St. John, Nakusp, Golden, Pine Pass, Port Alberni, Summerland, Terrace, Ver- non, Yoho National Park, Osoyoos Sil, 2 U8. Ge, BGP Me CLN-G. Det. : Dondale, Redner Arctosa alpigena (Doleschall). Yoho Valley Camp (8000’), Chilkat Pass, Manning Park, Forbidden Plateau, Lower Post, Vancouver (mountains north of), Tetsa River, Sikanni Chief River, Summit Lake (Alaska Highway), Glacier National Park, Mount Revelstoke Sie. 2 (CN. GU B.C: Det. : Dondale, Redner Arctosa emertoni Gertsch. See Dondale and Redner 1983, map 2. “British Columbia” S.L. : Unknown Det. : Dondale, Redner Arctosa littoralis (Hentz). See Dondale and Redner 1983, map 8. “British Columbia” S.L. : A.M.N.H. Det. : Dondale, Redner Arctosa perita (Latreille). Burnaby Sis @ “CN. Det. : Dondale, Redner Arctosa rubicunda (Keyserling). Yoho National Park Sk. = C.N.G. Det. : Dondale, Redner Pardosa albomaculata Emerton. Summit Lake (Alaska Highway), Mount St. Paul Sue “CNG: Det. : Redner Pardosa altamontis Chamberlin and _Ivie. Oliver, Okanagan Falls S.L. : Charles, C.N.C. Det. : Dondale, Redner Pardosa bucklei Kronestedt. Clinton S.L. : C.N.C., Buckle Det. : Redner Pardosa_ coloradensis Banks. Vernon, Sum- merland, Osoyoos, Kelowna, Orofino Mountain S.L. : C.N.C., Charles Det. : Dondale, Redner Pardosa concinna (Thorell). Apex Mountain (Keremeos), Summit Lake (Alaska Highway), Pink Mountain, Kamloops, Sum- merland, Lillooet, Mount McLean S.L. + B-G.P.M., G.N.C., U-B:C: Det. : Dondale, Redner Pardosa distincta (Blackwall). Sparwood, Goldstream Park Sols: “GeN CU, VIG: Det. : Redner J. ENTOMOL. SOc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 Pardosa diuturna Fox. Mount Arrowsmith, Garibaldi Park, Terrace, Jutland Mountain S.L. 7 C.N.C, Det. : Redner Pardosa dorsalis Banks. Apex Mountain (Keremeos), Kamloops, Manning Park, In- vermere, Yoho National Park S.L. : B.C.P.M., C.N.C., U.B.C. Det. : Redner, Lowrie, Dondale Pardosa dorsuncata Lowrie and Dondale. Cassiope Lake (Brooks Peninsula), Cape Cook Lagoon (Brooks Peninsula), Paradise Mine (9000’), Spectacle Lake, Pine Pass, Fort St. John, Barkerville, Burnaby, Salmon Arm, Revelstoke, Manning Park, Smithers, Alouette Lake, Terrace, Squamish, Metlakatla, Dawson Creek, Mount Needham (Queen Charlotte Islands), Com- ox, Victoria, Kyuquot, Heather Mountain, Mesachie Lake, Cowichan Lake, Tofino, Yoho National Park, Glacier National Park, Parksville S.L: : B.C.P.M., C.N.C. Det. : Redner, Dondale, Lowrie Pardosa furcifera (Thorell). Atlin, Sikanni Chief River, Summit Lake (Alaska Highway) Soles N-C; Det. : Dondale, Redner Pardosa fuscula (Thorell). Smithers, Tetsa River, Pink Mountain, Springhouse, Fort Nelson, Osoyoos S.L. : C.N.C., B.C.P.M., Buckle Collection Det. : Redner Pardosa groenlandica (Thorell) complex. Fort St. John, Dawson Creek, Sparwood, Clin- ton, Penticton, Paradise Mine, Vancouver Island, Kamloops S.5.. = U.VIG,; B:C.P.M., C.N:C; Det. : Redner, Kurata Pardosa hyperborea (Thorell). Atlin, Mile 150 Alaska Highway, Sikanni Chief River, Sum- mit Lake (Alaska Highway), Yoho National Park S:L.o¢ K.R:S. Det. : Leech Pardosa lapponica (Thorell). Summit Lake (Alaska Highway) S.be 2 CNC; Det. : Redner Pardosa lowriei Kronestedt. Kyuquot, Sidney, Sooke, Apex Mountain (Keremeos), Misin- chinkar River, San Juan River, Hazelton, Willows Beach (Victoria), Manning Park, Revelstoke, Pine Pass, Bijoux Falls Park, Patricia Bay S.L. : B.C.P.M., C.N.C., U.B.C. Det. : Dondale, Redner, Kronestedt Pardosa mackenziana (Keyserling). Fort St. James, Williams Lake, Salmon Arm, Trinity Valley, Pine Pass, Fort St. John, Kyuquot, Paradise Mine (9000’), Invermere, Clinton S.L. : U.B.C., BiG:P.M:, GING: Det. : Dondale, Kurata, Gertsch, Redner Pardosa metlakatla Emerton. Cape Cook Lagoon (Brooks Peninsula), Brasenia Lake (Brooks Peninsula), Kyuquot, Kalmia Lake (Brooks Peninsula), Metlakatla, North of Vancouver, Goldstream Park, Agassiz, Tofino, Metchosin S.L. : U.B.C., B.C.P.M., C.N.C., A.M.N.H. Det. : Dondale, Vogel, Redner, Gertsch Pardosa moesta Banks. Pouce Coupe, Victoria, Hazelton, Virginia Hills, Salmon Arm, Tetsa River, Prince George, Sikanni Chief River, Burnaby S.L. : B.C.P.M., C.NsG. Det. : Redner Pardosa palustris (Linnaeus). Chilkat Pass S.bs-- 2 GN-C. Det. : Redner Pardosa podhorskii Kulczynski. Pink Mountain Sc. CN. G: Det. : Redner Pardosa rainieriana Lowrie and Deondale. Lillooet S.b5°:>C.N.G, Det. : Dondale, Redner Pardosa sinistra (Thorell). Manning Park SL. 3+ CN.G. Det. : Redner Pardosa tesquorum (Odenwall). Windermere, Fort St. John, Tetsa River, Pink Mountain, Kamloops, Williams Lake, Prince George, Lower Post S.L. : A.M.N.H., B.C.P.M., C.N.C. Det. : Dondale, Redner Pardosa uintana Gertsch. Salmon Arm, Lower Post, Summit Lake (Alaska Highway), In- vermere, Tutshi River (59° 55’ N., 135° W.), Tetsa River, Sikanni Chief River, McBride, Tagish Lake, Pink Mountain S.L. : K.R.S., C.N.C. Det. : Leech, Redner, Dondale Pardosa vancouveri Emerton. Departure Bay, Vancouver, Lytton, Victoria, Galiano Island, Comox, Richmond, Hope, Sumas, Goldstream Park, Burnaby, Mesachie Lake, South Pender Island, Gibsons, Parksville S.L. : U.VIC., B.C.P.M., C.N.C., Buckle Det. : Redner, Gertsch Pardosa wyuta Gertsch. Summerland, Haney, Hope, Osoyoos, Goose Lake (Vernon), Queen Charlotte Islands, Kelowna, Golden, Burnaby, Goldstream Park, Willows Beach (Victoria), Rogers Pass, Lillooet S.L. : C.N.C., Charles Det. : Dondale, Redner Pardosa xerampelina (Keyserling). Golden, Yoho National Park, Revelstoke, Lillooet, Sumas, Hope, Bella Coola, Terrace, Fort Nelson, Lower Post, Racing River (Alaska Highway), Kamloops, Cottonwood, J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEC. 31, 1984 93 Smithers, Prince George, Sproat Lake, Fort St. John, Summerland, Sikanni Chief River, Pine Pass, Tetsa River Sauz = B.C.P.M., C.N.C: Det. : Redner, Leech Schizocosa mccooki (Montgomery). Apex Moun- tain, Osoyoos, Keremeos, Lillooet, Kamloops, Summerland, Oliver S.L. : B.C.P.M., C.N.C., U.B.C. Det. : Dondale, Redner Schizocosa minnesotensis (Gertsch). Oliver, Osoyoos, Cache Creek, Summerland S.L. : B.C.P.M., C.N.C. Det. : Dondale, Redner Melocosa fumosa (Emerton). Paradise Mine (9000), Yoho National Park S.L. : K.R.S.(?), R.O.M.(?), M.C.Z. Det. : Kurata, Leech FAMILY OXYOPIDAE Oxyopes scalaris Hentz. Summerland, Monte Creek, Penticton, Osoyoos, Vancouver, Departure Bay, Vernon, Oliver, Vaseux Lake, Victoria, Parksville, Spences Bridge, Lillooet, Pritchard, Walhachin, Trinity Valley, Kamloops, Fairview, Nicola Lake, Keremeos Creek S22 B.C. P5M;, C.N.C. Det. : Dondale FAMILY GNAPHOSIDAE Gnaphosa brumalis Thorell. Paradise Mine (9000), Summit Lake (Alaska Highway) Sa ¢.;B:C:.P.M., G.N.C. Det. : Kurata, Dondale, Redner, Platnick Gnaphosa californica Banks. Keremeos, Sum- merland, Osoyoos, Green Mountain (Keremeos) S.L. : Charles, C.N.C. Det. : Dondale, Redner, Platnick Gnaphosa microps Holm. Yoho National Park, Sikanni Chief River (17.5 km. S. on Alaska Highway) S.L.. + C.N.C; Det. : Platnick Gnaphosa muscorum (L. Koch). Keremeos, Trinity Valley, Oliver, Vaseux Lake, Princeton (12 miles east of), Blue Pool, Anar- chist Mountain, Cascade, Fountain Valley, Hedley, Lillooet, Nanoose Bay, Nelson, Radium, Revelstoke, Salmon Arm, Seton Creek, Summit Lake (Alaska Highway), Trail, Takla Landing, Wellington, Yalakom River, Yoho National Park, Apex Mountain (Keremeos) SG: UB CyB: C.P.M.,.C.N.C, Det. : Dondale, Redner, Platnick Gnaphosa parvula Banks. Kamloops, Tetsa River at Alaska Highway S-Ly > JC.N.C, Det. : Platnick Callilepis pluto Banks. Mount Benson, Well- ington, Quadra Island S.0., 2 -(C,N.Gi) UBC; Det. : Platnick Drassodes neglectus (Keyserling). Departure Bay, Atlin, Nanaimo, Oliver, Vernon, Well- ington, Apex Mountain (Keremeos), Green Mountain (Keremeos) Su. 2 GING Det. : Dondale, Redner, Platnick Drassodes saccatus (Emerton). Fountain Valley (Lillooet), Summerland, Green Mountain (Keremeos) S.L. : Charles, C.N.C. Det. : Dondale, Redner, Platnick Herpyllus hesperolus Chamberlin. Summerland S.L. : Charles, C.N.C. Det. : Dondale, Redner, Platnick Herpyllus propinquus (Keyserling). Osoyoos S.L. : Charles, C.N.C. Det. : Dondale, Redner, Platnick Drassyllus depressus (Emerton). Victoria, Buraby, Comox, Kyuquot, Mount Benson, Salmon Arm, Yale, Wellington S.L. : U.VIC., C.N.C. Det. : Dondale, Redner, Platnick Drassyllus dromeus Chamberlin. Oliver, Sum- merland, Green Mountain (Keremeos) S.L. : Charles, C.N.C. Det. : Dondale, Platnick Drassyllus insularis (Banks). Lillooet, Oliver, Summerland Sie = GING, Det. : Dondale, Redner, Platnick Drassyllus lamprus (Chamberlin). Summerland, Savona S.L. : Charles, C.N.C. Det. : Dondale, Platnick Drassyllus niger (Banks). Departure Bay, Hope, Wellington Si. = (GN G,..UB.G. Det. : Platnick Zelotes fratris Chamberlin. Sandspit, Terrace, Tagish Lake, Misinchinka River S.L.. :. B:C.P)M,, €.N.C. Det. : Dondale, Redner, Platnick Zelotes hentzi Barrows. Victoria, Wellington Sols @ ULB.C. Det. : Platnick Zelotes puritanus Chamberlin. Apex Mountain (Keremeos), Goldstream Park, Kamloops, Revelstoke, Summerland, Keremeos Creek S.L.. 2% B:C.P.M;, €.N.G. Det. : Redner, Platnick, Dondale Zelotes sula Lowrie and Gertsch. Manning Park, Manson Creek, Morley River Lodge, Summit Lake (Alaska Highway) S.L. : C.N.C., R.E.L. Det. : Platnick Zelotes tuobus Chamberlin. Departure Bay, Kamloops, Summerland S.L. : U.S.N.M., C.N.C., R.O.M. Det. : Platnick J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 Sergiolus columbianus (Emerton). Comox, Departure Bay, Goldstream Park, Langford, Wellington SL. ¢ °C.N.Ce UBC. Det. : Dondale, Redner, Platnick Sergiolus montanus (Emerton). Langford, Blue Pool Camp, Kamloops, Lillooet, Salmon Arm, Seton Creek, Terrace, Trinity Valley, Wellington, Summerland S.e 30. VIC. CN. Det. : Dondale, Redner, Platnick Haplodrassus_ bicornis (Emerton). Vernon, Westbank, Green Mountain (Keremeos) Sela. = CANEG. Det. : Dondale, Redner, Platnick Haplodrassus eunis Chamberlin. Golden (20 miles west of), Lillooet, Nelson, Matning Park, Apex Mountain (Keremeos) Srila eG N.C: Det. : Dondale, Redner, Platnick Haplodrassus signifer (C. L. Koch). Victoria, Departure Bay, Vaseux Lake, Oliver, Van- couver, Wellington, Westbank, Apex Moun- tain (Keremeos) SG. = CNG; Det. : Dondale, Redner, Platnick Orodrassus canadensis Platnick and Shadab. Atlin, Terrace, Forbidden Plateau SL. = CNC. Det. : Dondale, Redner, Platnick Orodrassus coloradensis (Emerton). Kamloops, Radium Hotsprings, Summit Lake (Alaska Highway), Kaslo Se lea 05 “CAN GS UB. Cae KGS, Det. : Dondale, Redner, Platnick, Leech Orodrassus orites Chamberlin and Gertsch. Manning Park Sil. -CoNeG: Det. : Platnick Nodocion eclecticus Chamberlin. Summerland S.L. : Charles, C.N.C. Det. : Platnick Nodocion voluntarius (Chamberlin). Summerland S.L. : Charles, C.N.C. Det. : Platnick Scotophaeus blackwalli (Thorell). Salmon Arm Sal.) =. ULB: Det. : Platnick Micaria pulicaria (Sundevall). Summerland, Terrace, Springhouse, Burnaby, Mesachie Lake, Salmon Arm, Oliver, Manning Park, Riske Creek, Revelstoke, Golden, Kyuquot SL 2 BG.PM.. G.N.C, Det. : Platnick, Gertsch FAMILY CLUBIONIDAE Cheiracanthium inclusum (Hentz). Chase, Oliver, Vaseux Lake, McIntrye Creek S.L. © C.NGC: Det. : Dondale, Redner Clubiona bryantae Gertsch. Pink Mountain Sil. 2 -C.NiC: Det. : Dondale, Redner Clubiona canadensis Emerton. McLeod Lake, Charlie Lake, Pine Pass, Manning Park, Lakelse Hotsprings, Hope, Terrace S:L. + B.C.P.MG) C.N7@} Det. : Dondale, Redner Clubiona kulczynskii Lessert. Prince George, Fort Nelson, Liard River, Teslin Lake, Sum- mit Lake (Alaska Highway), Tetsa River, Sikanni Chief River S:L: ¢ cG.N.G. Det. : Dondale, Redner Clubiona lutescens Westring. Vancouver S.L. : A.M.N.H. Det. : Dondale, Redner Clubiona mimula Chamberlin. Summerland, Vancouver S.L. : Charles, C.N.C., Bragg Det. : Dondale, Redner Clubiona moesta Banks. Salmon Arm, Osoyoos, Canoe, Lillooet S.L. : B.C.P.M:, C.N:G, Det. : Dondale, Redner Clubiona norvegica Strand. Goldstream Park S.L. + B:C.P.M.;.CLN:G. Det. : Dondale, Redner Clubiona pacifica Banks. Kyuquot, Triangle Island, Sartine Island, Wellington, Van- couver, Kaslo, Bear Lake, Glacier, Balfour, Ainsworth, Victoria, Metlakatla, Departure Bay, Qualicum, Cowichan Lake, Sidney, Goldstream Park, Masset, Comox, Errington S.L. 2 BsC.P.Mi; C.NG. Det. : Dondale, Redner Clubiona pallidula (Clerck). Vancouver S.L. : C.N.C., A.M.N.H. Det. : Dondale, Redner Clubiona praematura (Emerton). Chilkat Pass, Summit Lake (Alaska Highway), Pink Mountain 5.2 U:B GC. .C.N.G: Det. : Dondale, Redner Clubiona riparia L. Koch. Osoyoos, Kamloops S.L. : Charles Det. : Dondale, Redner Clubiona trivialis L. Koch. Cassiope Lake (Brooks Peninsula), Cape Scott, Yoho Na- tional Park, Manning Park, Hope, Lower Post S.Ey -: WBiG7, CNC: Det. : Dondale, Redner Castianeira longipalpa (Hentz). Osoyoos, Err- ington, Riske Creek, Williams Lake, Lum- by, Kamloops, Comox, Vancouver, Agassiz, Summerland, Francis Provincial Park S:.L. > BCP MM. C.N.G: Det. : Dondale, Redner Castianeira walsinghami (O.P.-Cambridge). Victoria, Prospect Lake, Salmon Arm, Min- nie Lake, Riske Creek S.L. : B.C.P.M., U.VIC. Det. : Dondale, Redner Agroeca ornata Banks. Salmon Arm, Revelstoke, Summerland, Trinity Valley, Lillooet S.L. : B.C.P.M., C.N.C. Det. : Dondale, Redner Agroeca pratensis Emerton. Summerland S.L. : Charles Det. : Dondale, Redner Phrurotimpus borealis (Emerton). Departure Bay, Salmon Arm, Oliver, Fountain Valley, Summerland, Hope, Mesachie Lake Selec CLN.G; Det. : Dondale, Redner Scotinella pugnata (Emerton). Kaslo, Terrace, Anarchist Mountain S.L. : Charles Det. : Dondale, Redner Scotinella sculleni (Gertsch). Saltspring Island S.l; >> G_N-C, Det. : Dondale, Redner FAMILY ANYPHAENIDAE Anyphaena aperta (Banks). Qualicum Falls, Victoria, Kyuquot, Errington S.L. : B.C.P.M., A.M.N.H. Det. : Redner, Gertsch, Platnick Anyphaena pacifica (Banks). Departure Bay, Osoyoos, Hope, Apex Mountain (Keremeos) S.L. : B.C.P.M., C.N.C., A.M.N.H. Det. : Dondale, Redner, Platnick FAMILY THOMISIDAE Tmarus angulatus (Walckenaer). Quesnel Si. ENC, Det. : Dondale, Redner Misumenops asperatus (Hentz). Vernon, Lillooet, Kelowna, Oliver, Summerland, Vaseux Lake Sale 8B. CP MEG. NEG: Det. : Leech, Redner Misumenops celer (Hentz). Victoria, Fairview, Oliver, Prospect Lake, Osoyoos, Cowichan Lake S:-L. 2 UWVIC.,BC.P.M,, C.N.C. Det. : Dondale, Redner Misumenops sierrensis Schick. Errington, Hope, Osoyoos So. 7 (BC.PiM.2G.N.G. Det. : Dondale, Redner Misumena vatia (Clerck). Salmon Arm, Kaslo, Manning Park, Metchosin, Lac la Hache, Kyuquot, Terrace, Princeton, Errington, Okanagan Falls, Metlakatla, Nanoose Bay, Victoria, Mitlenatch Island, Prince George, Stoner, Langford, Jackfish Creek, Tomslake, Cowichan Lake, Corbin, Penticton, Osoyoos, Jaffray, Prospect Lake, Kamloops, J. ENTOMOL. Soc. BriT. CoLuMBIA 81 (1984), DEc. 31, 1984 95 Trinity Valley, Vancouver, Babine Lake 5.0.2 7 -U.B.G,,.U VIC. B.G.P.Me-G.N.C: Det. : Dondale, Redner, Gertsch Ozyptila pacifica (Banks). Masset, Metlakatla, Terrace, Errington, Mission S.L. : B.C.P.M., C.N.C. Det. : Dondale, Redner Ozyptila septentrionalium L. Koch. Summit Lake (Alaska Highway) St. 2 aN. G. Det. : Dondale, Redner Coriarachne brunneipes Banks. Victoria, Well- ington, William Head, Nanoose Bay, Err- ington, Langford Sb. 2 UU VIG. B-C-P Me CON. G. Det. : Dondale, Redner, Bowling Coriarachne utahensis (Gertsch). Cottonwood, Langford, Osoyoos, Kyuquot, Cawston, Cultus Lake, Kelowna, Wellington, Fort Nelson, Terrace, Kaslo, Creston, Kamloops, Salmon Arm S.L. : U.VIC., B.C.P.M., C.N.C. Det. : Dondale, Redner, Leech, Gertsch, Bowling Xysticus benefactor Keyserling. Cawston, Osoyoos, Oliver, Hope, Nicola, Manning Park, Golden, Lemoray, Apex Mountain (Keremeos) S$. + B;/C.P.M., C.N.C, Det. : Dondale, Redner, Leech Xysticus canadensis Gertsch. Takla Landing, Summit Lake (Alaska Highway) Sk. 2 CNG, Det. : Dondale, Redner Xysticus cunctator Thorell. Vernon, Well- ington, Departure Bay, Victoria, Oyster River, Fountain Valley (near Lillooet), Lyt- ton, Hedley, Rock Creek, Apex Mountain (Keremeos), Cherryville, Kamloops, Prit- chard, Green Mountain Sucs & U-B CBC, beMs UVC. GC NaG. Det. : Dondale, Redner Xysticus discursans Keyserling. Cawston, Hedley, Yoho National Park, Okanagan Falls, Kaslo, Kamloops S-L.. » U.B.C,,.C.N-C. Det. : Dondale, Redner Xysticus durus (Soerensen). Summit Lake (Alaska Highway) S.L. : Leech Det. : Dondale, Redner Xysticus elegans Keyserling. Seton Creek, Foun- tain Valley (near Lillooet), Salmon Arm SL. 2 BC PM... C_N.C. Det. : Dondale, Redner, Leech Xysticus emertoni Keyserling. Okanagan Falls, Summit Lake (Alaska Highway), Sparwood, Pouce Coupe, Liard Hotsprings Sols. B CIP Mo UGV1GseG, NeG; Det. : Dondale, Redner Xysticus ferox (Hentz). Summit Lake (Alaska J. ENTOMOL. Soc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 Highway), Langford, Sparwood S.L. : U.VIC., C.N.C. Det. : Dondale, Redner Xysticus gertschi Schick. Departure Bay, Cawston, Spences Bridge, Cache Creek, Kamloops, Lytton, Keremeos Creek S.L. : Charles, C.N.C. Det. : Dondale, Redner Xysticus gosiutus Gertsch. Wellington, Depar- ture Bay, Langford Sl. 2 UVic. GUNG, Det. : Dondale, Redner Xysticus gulosus Keyserling. Fountain Valley (near Lillooet), Hermead, Cawston, Keremeos, Victoria, Osoyoos, Vernon, Walhachin SL. 2 U. BiG... BG.PM..’E.N:G. Det. : Dondale, Redner, Leech Xysticus keyserlingi Bryant. Mount St. Paul S.L..°2 *C.N.C. Det. : Dondale, Redner Xysticus locuples Keyserling. Langford, Well- ington, Departure Bay, North Vancouver, Cultus Lake, Fountain Valley, Clinton, Cawston, Okanagan Falls, Lillooet, Kamloops, Spences Bridge, Oliver, Osoyoos, Green Mountain (Keremeos) S.L.-= U.VIC.; B:C.P.M., C.N.C. Det. : Dondale, Redner Xysticus luctuosus (Blackwall). Summit Lake (Alaska Highway), Fort Nelson, Sardis, Agassiz, Fountain Valley (near Lillooet), Hope, Chase, Mill Bay, Apex Mountain (Keremeos) 5.0: BoC:P M.,-C.N-C: Det. : Dondale, Redner, Leech Xysticus montanensis Keyserling. Wellington, Comox, Oliver, Kaslo, Courtenay, Riske Creek, Vernon, Victoria, Parksville, Brasenia Pond (Brooks Peninsula), Summerland S.L... 2 U.B.C,, B.C.P.M., C.N.C. Det. : Dondale, Redner Xysticus obscurus Collett. Summit Lake (Alaska Highway), Liard River Hotsprings, Sikanni Chief River at Alaska Highway S.l,-2) CNG. Det. : Dondale, Redner Xysticus pretiosus Gertsch. Kyuquot, Terrace, Departure Bay, Lytton, Victoria, Errington, Sproat Lake, Cape Cook, Cassiope Lake (Brooks Peninsula), Triangle Island, Langford, Spuzzum S.L. : B.C.P.M., U.VIC., C.N.C. Det. : Dondale, Redner, Gertsch Xysticus punctatus Keyserling. Salmon Arm, Fountain Valley (Lillooet), Fort Nelson, Kaslo, Radium Hot Springs, Fairmont Hotsprings, Prince George S-L. + B.C:P.M., C.N.C. Det. : Dondale, Redner Xysticus triangulosus Emerton. Atlin, Summit Lake (Alaska Highway), Fountain Valley (near Lillooet), Goodfellow Creek, Hope (10 miles north of) S.L. : B-C:P™M.,C.N.C, Det. : Dondale, Redner Xysticus triguttatus Keyserling. Summit Lake (Alaska Highway), Field S, Lise &G_N.C. Det. : Dondale, Redner FAMILY PHILODROMIDAE Ebo pepinensis Gertsch. Wellington Selis ot? (P) Det. : Platnick Philodromus alascensis Keyserling. Michel, Stag Leap Prov. Park, Courtenay, Salmon Arm, Forbidden Plateau (3000’), Mount St. Paul, Summit Lake (Alaska Highway), Wycliffe, Okanagan Falls, Manning Park, Barkerville, Garibaldi Park S.L.° 2) B-CyP.Mis ‘CNC: Det. : Dondale, Redner Philodromus califoricus Keyserling. Vaseux Creek, Summerland, Osoyoos S.L. : Charles, C.N.C. Det. : Dondale, Redner Philodromus cespitum (Walckenaer). Osoyoos, Fairview, Okanagan Falls, Penticton, Foun- tain Valley, Canim Lake, Mons Lake, Kelowna, Windermere, Sparwood, Kamloops S.L: 2B. C.P.M:,.U.B.Cu“G7Ne@: Det. : Dondale, Redner Philodromus dispar Walckenaer. Langford, Victoria, Vancouver, Cowichan Lake, Wellington S.L. + BICP.M;, U.VIC.|“C.N.C, Det. : Dondale, Redner Philodromus histrio (Latreille). Osoyoos, Kelowna, Vaseux Lake, Spences Bridge, Summerland, Lytton, Walhachin, White Lake (Okanagan Falls), Cache Creek S.L; >? B.C.P.M.,C.N.C; Det. : Dondale, Redner Philodromus insperatus Schick. Summerland, Vernon, Lytton, Okanagan Falls, Keremeos Creek S.L. : Charles, C.N.C. Det. : Dondale, Redner Philodromus josemitensis Gertsch. Comox, Cowichan Lake, Victoria S-L. 2 CIN, Det. : Dondale, Redner Philodromus mysticus Dondale and Redner. Terrace Silis 3 “CNG. Det. : Dondale, Redner Philodromus oneida Levi. Lillooet, Manning Park, Duncan S.L. 2 G.N:G: Det. : Dondale, Redner Philodromus pernix (Blackwall). Cawston, Kamloops Seen GNC: Det. : Dondale, Redner Philodromus placidus Banks. Rock Creek, Liard Hotsprings, Cache Creek, Fountain Valley S.L. : Charles, C.N.C. Det. : Dondale, Redner Philodromus praelustris Keyserling. Elko, Pen- ticton, Lillooet S.L. = B-C.P.M., C.N.C. Det. : Dondale, Redner Philodromus rodecki Gertsch and _ Jellison. Cache Creek, Lytton S.L. : B.C.P.M. Det. : Dondale, Redner Philodromus rufus pacificus Banks. Spuzzum, Osoyoos, Lemoray, Langford, Hollyburn Ridge, Cassiope Lake (Brooks Peninsula), Canim Lake, Kyuquot, Lillooet S.L. : U.VIC., B.C.P.M., C.N.C. Det. : Dondale, Redner Philodromus rufus quartus Dondale and Redner. Liard Hotsprings, Prophet River (57° 58’ N, 122° 47° W) Seb s OG NEG. Det. : Dondale, Redner Philodromus speciosus Gertsch. Okanagan Falls S.L. : Charles, C.N.C. Det. : Dondale, Redner Philodromus spectabilis Keyserling. Masset, Vassant, Wellington, Mount Benson, Lillooet, Cascade, Port Alberni, Errington, Lytton, Cowichan Lake SLs B.C. PM. CNC. Det. : Dondale, Redner Apollophanes margareta Lowrie and Gertsch. Summerland, Fountain Valley, Sidney, Quesnel S.L. : C.N-C. Det. : Dondale, Redner Thanatus arcticus Thorell. Summit Lake (Alaska Highway) Sly fo O.N-G. Det. : Dondale, Redner Thanatus_ coloradensis Keyserling. Osoyoos, Kamloops, Terrace, Pritchard 5 eas Det. : Dondale, Redner Thanatus formicinus (Clerck). Wellington, Kamloops, Penticton, Salmon Arm, Oliver, Keremeos Creek, Apex Mountain (Keremeos) S.L. = BeC.P.M.. U.B.C: Det. : Dondale, Redner Thanatus patricia (Lowrie and Gertsch). Mann- ing Park S.L. : Bragg Det. : Leech Thanatus striatus L. Koch. Comox, Oliver, Okanagan Falls J. ENTOMOL. SOc. BRIT. COLUMBIA 81 (1984), DEc. 31, 1984 97 Sb oe GEN.G: Det. : Dondale, Redner Tibellus chamberlini Gertsch. Summerland, Oliver S.L. : Charles, C.N.C. Det. : Dondale Tibellus gertschi Chamberlin and_ Ivie. Cawston, Yale, Princeton S: Le 2 CNG, Det. : Dondale, Redner Tibellus maritimus (Menge). Jackfish Creek, Pouce Coupe, Fort Nelson, Oliver, Osoyoos S.L. : B.C.P.M., C.N.C. Det. : Dondale, Redner Tibellus oblongus (Walckenaer). Errington, Mitlenatch Island, Kyuquot, Brasenia Pond (Brooks Peninsula), Cape Cook, Trinity Valley, Victoria, Sparwood, Nanoose Bay, Yahk, Spuzzum, Vernon, Fairmont, Apex Mountain (Keremeos) S:L. 2. U.B:C.,.B.G.P.M.,-U.VIG., G:N.G Det. : Dondale, Redner, Gertsch FAMILY SALTICIDAE Evarcha hoyi (Peckham and Peckham). Kyu- quot, Victoria, Metlakatla, Manning Park, Langford, Brasenia Pond (Brooks Penin- sula), Dougan Lake, Pouce Coupe, Creston, Cape Cook Lagoon (Brooks Peninsula), Tomslake, Sparwood, Fife, Qualicum Falls, Summerland SL, > Ue VIC. BC. Mi CLN:G. Det. : Dondale, Gertsch, Kurata Habronattus americanus (Keyserling). Victoria, Clinton, Apex Mountain (Keremeos) S.L. : C.N.C., U.B.C. Det. : Dondale, Maddison, Griswold Habronattus hirsutus (Peckham and Peckham). Vernon, Green Mountain (Keremeos), Summerland S.L. : Charles, C.N.C Det. : Dondale Habronattus jucundus Peckham and Peckham. Glacier National Park S.L. : M.C.Z. Det. : Peckhams Habronattus oregonensis (Peckham and Peckham). Kyuquot S.L; : B.C.P.M., C.N.C. Det. : Gertsch Habronattus sansoni (Emerton). Osoyoos, Lillooet Sila. 2 CINC, Det. : Griswold Pellenes laggani Peckham and Peckham. Glacier National Park, Victoria Sle 2 IMEC 7s Det. : Peckhams Pellenes montanus (Emerton). Apex Mountain (Keremeos) or Dear al O66 334 Os Det. : Dondale 98 J. ENTOMOL. Soc. BrIT. COLUMBIA 81 (1984), DEc. 31, 1984 Sitticus absolutus Gertsch and Mulaik. Kelowna, Kamloops, Vernon, North Van- Summerland couver, Salmon Arm, Nicola, Victoria, Si GN, Enderby Det. : Maddison S.L.. + U.B.C., UNIC.. B.C.P.M. Sitticus finschi (L. Koch). Terrace Det. : Dondale Sa. 2 CUNT G: Neon reticulatus (Blackwell). Lake Cowichan, Det. : Maddison Terrace, Wellington Sitticus lineolatus (Grube). Summit Lake, Yoho S.L. : C.N.C., A.M.N.H. and Glacier National Parks, White Pass Det. : Maddison S.L. : U.BC., M.C.Z., C.N.C. Metaphidippus helenae (Banks). Monte Creek Det. : Dondale So Lc 3 GsN.G, Sitticus palustris (Peckham and Peckham). Det. : Dondale Yoho, Goldstream Park Metaphidippus manni (Peckham and Peckham). S.L. : C.N.C. Savary Island, Saltspring Island, Vancouver Det. : Dondale S.L. : C.N.C., U.B.C, Salticus scenicus (Clerck). Victoria, Vancouver, Det. : Gertsch Lytton, Sooke, Langford, Penticton, Metaphidippus montanus (Emerton). Sum- Kamloops, New Westminster merland, Tomslake, Osoyoos, Prophet River S.L. 2 U.B:G., U.V1IG., B’C.P.M, (57° 68 N, 122° 47 W), Tetsa River Det. : Dondale, Redner Si. =. GNC, Metacyrba californica (Peckham and Peckham). Det. : Dondale Victoria, Vernon, Saltspring Island, Err- Metaphidippus protervus (Walckenaer). ington, Mitlenatch Island, Osoyoos, Summerland Mesachie Lake S.L.' & -G.NIG, S.L. : B.C.P.M., C.N.C. Det. : Dondale Det. : Dondale Metaphidippus vitis (Cockerell). Osoyoos, Phidippus johnsoni (Peckham and Peckham). Summerland Nanaimo, Victoria, Langford, Vernon, S.L..¢-G.N.C, Stoner, Elko, Duncan, Vancouver, Queen Det. : Dondale Charlotte Island, Grand Forks, Clinton Sassacus papenhoei Peckham and Peckham. S.L. : U.VIC., B.C.P.M., C.N.C. Spences Bridge, Summerland, Walhachin Det. : Dondale Si: CNC. Phidippus purpuratus Keyserling. Osoyoos Det. : Dondale S.L. : B.C.P.M., C.N.C. Talavara minuta (Banks). Apex Mountain Det. : Dondale (Keremeos) Eris marginata (Walckenaer). Pouce Coupe, Ss L..4. ULB.C. Cowichan, Lumby, Creston, Sparwood, Det. : Dondale REFERENCES Brignoli, P. M. 1978. Quelques notes sur les Agelenidae, Hahniidae, Oxyopidae et Pisauridae de France et d’Espagne (Araneae). Rev. suisse Zool. 85:265-294. Dondale, C. D. and J. H. Redner. 1983. Revision of the wolf spiders of the genus Arctosa C. L. Koch in North and Central America (Araneae : Lycosidae). J. Arachnol. 11:1-30. Helsdingen, P. J. van. 1973. A recapitulation of the Nearctic species of Centromerus Dahl (Araneida, Linyphiidae) with remarks on Tunagyna debilis (Banks). Zool. Verh. Rijksmus. Nat. Hist. Leiden, No. 124. 45 pp. Holm, A. 1950. Studien uber die Spinnenfauna des Tornetraskgebietes. Zool. Bidr. Upps. 29:103-213. Levi. H. W. 1971. The diadematus group of the orb-weaver genus Araneus north of Mexico (Araneae : Araneidae). Bull. Mus. Comp. Zool.. Harv. Univ. 141 (4) :131-179. Levi, H. W. 1977. The orb-weaver genera Metepeira, Kaira and Aculepeira in American north of Mexico (Araneae : Araneidae). Bull. Mus. Comp. Zool. Harv. Univ. 148 (5) :185-238. Millidge, A. F. 1980. The erigonine spiders of North America. Part 2. The genus Spirembolus Chamberlin (Araneae : Linyphiidae). J. Arachnol. 8:109-158. Millidge, A. F. 1981. The erigonine spiders of North America. Part 3. The genus Scotinotylus Simon (Araneae : Linyphiidae). J. Arachnol. 9:167-213. Millidge, A. F. 1983. The erigonine spiders of North America. Part 6. The genus Walckenaeria Blackwall (Araneae, Linyphiidae). J. Arachnol. 11:105-200. Thorn, E. 1967. Preliminary distributional list of the spiders of British Columbia. Rep. Prov. Mus. Nat. Hist. Anthrop. Br. Columbia (1966) 17 pp. J. ENTOMOL. Soc. Brit. COLUMBIA 81 (1984), DEC. 31, 1984 99 CBE STYLE MANUAL Fifth Edition A guide for Authors, Editors, and Publishers in the Biological Sciences Widely accepted and recommended as _ the standard reference for journals and books in the biological sciences Special features of this newly updated and greatly expanded edition include: e four new chapters; ® complete revision of the section © reorganization of the ‘‘Manuscript on ‘‘Plant Sciences’’; Preparation’’ section for easier ® cross-listing of ‘‘Abbreviations reference; and Symbols’’; ® new conventions in the chapter on ‘*Style in Special Fields’’; and much more... 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V8Z 1M5 ISSN 40071-0733 J Oo U 4 N A \5 of the ENTOMOLOGI Iested December 44,1085 ECONOMIC Grimes & Cone — Control of the grape mealybug Pseudococcus maritimus, (Hom.:Pseudococcidae), on Concord grape in Washington Hathaway, Mayer & Lunden — Efficacy of pesticides on the western spotted tentiform leafminer (Lepidoptera:Gracillariidae) in the Pacific northwest Gillespie — Endemic Aleyrodidae (Homoptera) and their parasites (Hymenoptera) on southern Vancouver Island, British Columbia Messing & AliNiazee — Natural enemies of Myzocallis coryli (Hom.:Aphididae) in Oregon hazelnut orchards Hathaway, Moffitt & George — Codling moth (Lepid.:Tortricidae): Disruption of sexual communication with an antipheromone [(E,E)-8,10-dodecadien-1-O1 acetate] Sites & Cone — Vertical dispersion of twospotted spider mites on hops throughout the growing season Fuchs & Borden — Pre-emergence insecticide applications for control of the mountain pine beetle, Dendroctonus ponderosae (Coleoptera:Scolytidae). ..........-.-.-.-: 25 McMullen & Safranyik — Some effects of pine oil on mountain pine beetle (Col.:Scolytidae) at different population levels Angerilli & Logan — Early season apple pest management: control of two species of scales (Homo.:Diaspididae) and bruce spanworm (Lep.:Geometridae) with methidathion 31 GENERAL Mitchell, Bates, Winston & McCutcheon — Comparison of honey bee queens overwintered individually and in groups Forbes, Chan, Raine & McMullen — Aphids trapped in Okanagan cherry orchards and the failure of nine species to transmit little cherry disease Humble — Seasonal activity of Ichneumonid pupal parasitoids of Operophtera spp. (Lepidoptera: Geometridae) Barstow & Getzin — The seasonal activity of Trachyphloeus bifoveolatus (Coleoptera:Curculionidae) in western Washington Safranyik & Linton — Influence of competition on size, brood production and sex ratio in spruce beetles (Col.:Scolytidae) TAXONOMIC Forbes & Chan — The aphids (Homoptera: Aphididae) of British Columbia 13. further additions Hamilton — Taxa of Idiocerus Lewis new to Canada (Rhynchota: Homoptera: Cicadellidae) Scudder — Heteroptera new to Canada NOTICE TO CONTRIBUTORS ISSN 40071-0733 J oO URNAL of the ENTOMOLOGICAL SOCIETY of BRITISH COLUMBIA Vol. 82 Issued December 31, 1985 ECONOMIC Grimes & Cone — Control of the grape mealybug Pseudococcus maritimus, (Hom.:Pseudococcidae), on Concord grape in Washington ..................... 3 Hathaway, Mayer & Lunden — Efficacy of pesticides on the western spotted tentiform leafminer (Lepidoptera:Gracillariidae) in the Pacific northwest ................. fi Gillespie — Endemic Aleyrodidae (Homoptera) and their parasites (Hymenoptera) on southern Vancouver Island, British Columbia .................. 0.000 cece eeeee 12 Messing & AliNiazee — Natural enemies of Myzocallis coryli (Hom.:Aphididae) in Oregon HazelnuteOrCnarGS: 5, <4c4 ese een ee oac eA las £24 Pela a eee OEE Bee Ben 14 Hathaway, Moffitt & George — Codling moth (Lepid.:Tortricidae): Disruption of sexual communication with an antipheromone [(E,E)-8,10-dodecadien-1-O1 acetate] ..... 18 Sites & Cone — Vertical dispersion of twospotted spider mites on hops throughout the PE OWANEASCASOM se ee hE je he he we aie athe teen ee ne teem os e Gm ara de wee 22 Fuchs & Borden — Pre-emergence insecticide applications for control of the mountain pine beetle, Dendroctonus ponderosae (Coleoptera:Scolytidae). .................. 25 McMullen & Safranyik — Some effects of pine oil on mountain pine beetle (Col.:Scolytidae) at different population levels ................. 0.0.0. e eee eee 29 Angerilli & Logan — Early season apple pest management: control of two species of scales (Homo.:Diaspididae) and bruce spanworm (Lep.:Geometridae) with methidathion 31 GENERAL Mitchell, Bates, Winston & McCutcheon — Comparison of honey bee queens overwintered individually and in groups ................ 00. cee eee eee eee neces 35 Forbes, Chan, Raine & McMullen — Aphids trapped in Okanagan cherry orchards and the failure of nine species to transmit little cherry disease ...................6... 39 Humble — Seasonal activity of Ichneumonid pupal parasitoids of Operophtera spp. (cepidoptera: Geometridae): 6. isan Secl. ooo. 2h ea ee hee pele ood de olen 44 Barstow & Getzin — The seasonal activity of Trachyphloeus bifoveolatus (Coleoptera:Curculionidae) in western Washington ...................0 0000 eee 47 Safranyik & Linton — Influence of competition on size, brood production and sex ratio in spruce: bectles(Col::Scolytidae): 46.054 svete os das sw oso de da dae ewes 52 TAXONOMIC Forbes & Chan — The aphids (Homoptera: Aphididae) of British Columbia 13. further CLL ONS gee rm Peete tacos! mie tare wean, ey cetea ve fctenic eee eae a ee ee ee 56 Hamilton — Taxa of Idiocerus Lewis new to Canada (Rhynchota:Homoptera:Cicadellidae) ........... 0.0.0 cc eects 59 Scudder — Heteroptera new to Canada ............... 0.0 ccc cece cece teens 66 NOTICE ATO GONTRIBUT ORS 22 5 oot foe sae eee ele eas G26 dee ews te 72 J. ENTOMOL. Soc. Brit. COLUMBIA 82 (1985), DEc. 31, 1985 DIRECTORS OF THE ENTOMOLOGICAL SOCIETY OF BRITISH COLUMBIA FOR 1984-1985 President Nello Angerilli Agriculture Canada, Summerland President-Elect Rob Cannings B.C. Provincial Museum, Victoria Past President Richard Ring University of Victoria, Victoria Secretary-Treasurer Gordon Miller Pacific Forestry Centre, Victoria Editorial Committee (Journal) H. R. MacCarthy R. Ring A. R. Forbes Editor (Boreus) R. Cannings Directors J. Harris (2nd) B. Roitberg (2nd) J. Sweeney (Ist) S. Lindgren (Ist) M. Isman (Ist) Hon. Auditor I. Otvos Regional Director of National Society R. Cannings B.C. Provincial Museum, Victoria J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEC. 31, 1985 3 | CONTROL OF THE GRAPE MEALYBUG!, PSEUDOCOCCUS MARITIMUS, (HOM.: PPEUDOCOCCIDAE), ON CONCORD GRAPE IN WASHINGTON ELIZABETH W. GRIMES? AND WYATT W. CONE? Department of Entomology, Washington State University Irrigated Agriculture Research and Extension Center Prosser, WA 99350 ABSTRACT Ten insecticides were evaluated for control of the mealybug, Pseudococcus maritimus (Ehrhorn), (Homoptera: Pseudococcidae) on Concord grape in southcentral Washington during 1981 and 1982. Efficacy was determined from the number of mealybugs in samples taken throughout the season and frompreharvest evaluation of mealybug damage (honeydew and sooty mold, Clasdosporium sp.) to fruit clusters. Results showed that parathion, malathion, and permethrin (Am- bush®) effectively reduced mealybug numbers and resulted in reduced damage to clusters. INTRODUCTION The grape mealybug, Pseudococcus maritimus (Ehrhorn), is an economic pest on grapes (Flebut 1922), pears (Madsen and Westigard 1962), apricots (Madsen and McNelly 1960), and Taxus spp. nursery stock (Neiswander 1949). Mealybugs are sessile feeders. As they feed they excrete large amounts of honeydew which collects on the berries and provides a suitable substrate for black sooty mold, Cladosporium sp. Grape berry clusters con- taminated by honeydew, sooty mold, or insect parts have reduced value or may be unsaleable (Stafford and Kido 1955). Early researchers fumigated to control grape mealybug on Vitis sp. stock, but were unsuccessful (Flebut 1922). Since the 1950’s parathion has been the most widely used pesticide for mealybug con- trol. It has proven effective as a delayed-dormant spray with oil (Jensen et al. 1964) and as a summer spray or dust (AliNiazee and Stafford 1972). Sum- mer sprays are unacceptable for table grapes as they reduce bloom, but they may be used on processed grapes (Frick and Bry 1955). The grape mealybug was first reported as a pest in Washington vineyards in 1950. Since then it has been controlled with parathion (Frick 1952) and malathion (Cone 1971). Although parathion has been the standard control measure for grape mealybug for 30 years, vineyards with intense spray histories are developing more resistant grape mealybug populations (Jensen et al. 1964). Flaherty et al. (1982) indicated that the mealybug can develop resistance to parathion. Alternatives to parathion must be found for grape mealybug control. The objectives of this study were 1) to evaluate parathion and malathion for control of the grape ‘Homoptera: Pseudococcidae. *Research Assistant, Entomology. ’Entomologist. We thank Larry Wright and Joe Perez for aid in this study and the Columbia River Orchard Foundation for partial funding. Washington State University, Scientific Paper Number 7080. mealybug in southcentral Washington to determine if resistance had developed, and 2) to screen several non-organophosphate insecticides for comparable efficacy. Superior oil with and without insecticide was also evaluated as a control. MATERIALS AND METHODS Insecticide trials were conducted on Concord grape, Vitis labrusca L., vineyards at the Irrigated Agriculture Research and Extension Center near Prosser, Washington. The 0.8-hectare vineyard, un- treated for five years before the experiment began, supported a natural grape mealybug infestation. Plots consisted of 6 replications of 6 vines each, in a randomized complete block design for 10 treatments. In 1981 delayed-dormant sprays were applied on 14-17 April and in 1982 on 22-23 April using the same plot design. The sprays were applied at 21,000 g/cm? using a Bean Speed Sprayer® with a nozzle arrangement designed for maximal coverage of the vine. Sprays were applied to both sides of each plot using either the right or left bank of nozzles on the sprayer. The spray volume (3,785 I/ha) soaked the outer bark and allowed penetration of the pesticide under the bark. Five emulsifiable concentrates, 2 wettable powders, and 3 oils were applied to the treated plots (Table 1). Plot rows were separated by unsprayed border rows and un- treated plots served as the control. Two large canvas shields (Fig. 1) were used to prevent cross-row con- tamination. One, mounted on a second tractor, was moved along the row opposite the sprayer nozzles. Since much of the spray rolled back from the pro- tective shield and drifted in the opposite direction, a second shield was mounted on the back of the sprayer to effectively prevent any plot contamination. Early in the season mealybugs were collected from rough bark samples taken from the trunk and lateral arms. As the season progressed leaf and shoot material was sampled, and finally fruit clusters were included. The early season vine samples were weighed, and placed in Berlese funnels for 24 hours. The mealybugs were collected in vials of 70% ethyl 4 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 TABLE 1. Number of mealybugs per 10 g of Concord grape vine material from experimental plots treated with insecticide, Prosser, Washington, 1981. Insecticide used and formulation Parathion 8EC + oi1° Permethrin 2EC + oi] Malathion 5EC + oi] Parathion 8EC + oil Phosmet 5OWP Oi] 01] 011 Phosmet 50WP + 07] Untreated | * The rates of oi] Rate (kg Al/ha)? 1981 Number of Mealybugs per 10 g sample> alone are in litres/hectare. : Figures followed by the same letter are not significantly different, DMRT (P = 6.05). © All insecticides applied with oil at 18.95 litres of oil/hectare. alcohol placed below the funnels, and counted later. An index using the number of mealybugs per 10 g of vine material was established to facilitate analysis of the data. Mealybug damage to clusters was determined just prior to harvest. Damage con- sisted of contamination by honeydew secreted by the mealybugs and/or the growth of sooty mold on the honeydew. Samples consisted of 6 clusters per plot (4 from the top vine-support wire and 2 from the bottom wire) collected near the main trunk. The clusters were pulled apart and each individual berry inspected for the presence of mealybugs and % honeydew contamination. RESULTS AND DISCUSSION Results from monitoring the grape mealybug population throughout the growing season in 1981 is summarized in Table 1. Plots treated with parathion + oil or permethrin (Ambush®) + oil had significantly fewer mealybugs than the other treatments. Plots sprayed with malathion + oil, phosmet (Imidan®), or high concentrations of oil alone also had fewer mealybugs when compared to phosmet + oil or the untreated plots. The same treatments were re-applied and similar data were collected in 1982. However, significant differences were not obtained due to an overall reduced mealybug population in the vineyard. In 1981 plots treated with malathion + oil, parathion+oil, and permethrin+oil had significantly less honeydew contamination of clusters than the other plots (Table 2). Comparison of percent berries with sooty mold and/or mealybugs in 1981 closely paralleled the results for contamination of clusters with honeydew. For 1982, the percent of berries with sooty mold and/or mealybugs among treatment plots was not J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 5 TABLE 2. Percent Concord grape berries* with honeydew contamination in insecticide treated plots, Pro- sser. 1981-82. Insecticide used and formulation Malathion 5EC + oi1¢ Parathion 8EC + oil Phosmet 50WP + o7] Parathion, SEC + O11 Permethrin 2EC + oi] 0i1 Phosmet 50WP Untreated Oi] 071 Rate (kg Al/ha)? Percent berries with honeydew® 1981 1982 @ Taken from 66 fruit clusters in 1981 and 36 clusters in 1982. b The rates of 01] alone are in litres/hectare. Figures followed by the same letter are not significantly different, DMRT (P = 0.05). d significantly different due to a reduced mealybug population. The decrease in P. maritimus numbers in 1982 may have resulted from several factors: 1) the 1981 spray program may have reduced numbers enough to affect the 1982 population and, 2) mummies of parasitized mealybugs were collected in the vineyard in 1981 and 1982, so that parasitism may have reduced the population. Quantification of mealybug damage to clusters in 1982 was further complicated by atypical preharvest rains which washed off much of the honeydew. The parathion+oil, malathion+oil, or permethrin + oil-treated plots which showed low infestation levels of mealybugs throughout the All insecticides applied with oi] at 18.95 litres of oil/hectare. season also had less fruit cluster contamination by mealybugs and mealybug products at harvest. Phosmet without oil or 15.16 | of oil alone produced consistent, yet less effective, control of mealybugs and their damage. Phosmet + oil or low concentra- tions of oil alone were inconsistent and gave poor control of the mealybug. These data support a positive correlation between the mealybug numbers in the vineyard throughout the growing season and the economic damage to fruit clusters at harvest. Thus, early season estimates of mealybug density may aid growers in making decisions on summer spray management. Grape mealybug resistance to organophosphates was not apparent; both parathion and malathion 6 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 Fig. 1. Canvas shields arranged to prevent cross-row contamination of plots by insecticides during application. provided effective control in this trial. However, | mealybug population. The effect of the treatments because the vineyard had been unsprayed for 5 on the natural control agents of the mealybug is years before the study began, mealybug resistance _ uncertain as a large portion of the vineyard remain- may have been very low. Also, a large predator and _ ed unsprayed and could have served as a reservoir parasite population could have depressed the for parasites and predators. REFERENCES AliNiazee, M. T., and E. M. Stafford. 1972. Control of the grape mealybug on “Thompson Seedless’ grapes in California. J. Econ. Entomol. 65:1744. Cone, W. W. 1971. Grape mealybug control in Concord field trials in central Washington. J. Econ. En- tomol. 64:1522-3. Flaherty, D. L., W. L. Peacock, L. Bettiga, and G. M. Leavitt. 1982. Chemicals losing effect against the grape mealybug. Calif. Agric. 36:15-6. Flebut, A. J. 1922. The grape mealybug. Calif. Dep. Agric. Bull. 11:7-11. Frick, K. E. 1952. The value of some organic phosphate insecticides in control of the grape mealybug. J. Econ. Entomol. 45:340-1. Frick, K. E., and R. E. Bry. 1955. Dormant vs. summer control of the grape mealybug in the Yakima Valley. J. Econ. Entomol. 45:607-8. Jensen, F., D. Flaherty, E. M. Stafford, and H. Kido. 1964. Developments in control of the grape mealybug. J. Econ. Entomol. 57:372-4. Madsen, H. F., and L. B. McNelly. 1960. Control of the grape mealybug on apricots. J. Econ. Entomol. 53:354-7. Madsen, H. F., and P. H. Westigard. 1962. Behavior and control of the grape mealybug on pear. J. Econ. Entomol. 55:849-50. Neiswander, R. B. 1949. The grape mealybug on Taxus in Ohio, J. Econ. Entomol. 42:41-43. Stafford, E. M., and H. Kido. 1955. Control of the grape mealybug in California. J. Econ. Entomol. 48:101-2. : Key words: grape mealybug, Pseudococcus maritimus, Concord grape, Vitis labrusca, permethrin. J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEC. 31, 1985 EFFICACY OF PESTICIDES ON THE WESTERN SPOTTED TENTIFORM LEAFMINER (LEPIDOPTERA:GRACILLARITDAE) IN THE PACIFIC NORTHWEST D. O. HATHAWAY, D. F. MAYER’, AND J. D. LUNDEN! Yakima Agricultural Research Laboratory Agricultural Research Service, U. S. Department of Agriculture Yakima, Washington 98902 ABSTRACT A serious infestation of the western spotted tentiform leafminer, Phyllonorycter elmaella Doganlar and Mutuura, was discovered in a commercial apple orchard in southeastern Washington in 1980. By 1983, the insect was found in many orchards in Washington, northern Oregon, and parts of Idaho on the foliage of apple, cherry, pear, and prune trees. A number of insecticides were tested against the leafminer in the Kennewick, Pasco, Prosser, and Moxee areas of Washington during 1983 and 1984. In one orchard, early season control was best with oxamyl, permethrin, cypermethrin and diflubenzuron. In another orchard, oxamyl, endosulfan at pink stage, an endosulfan-methoxychlor mix applied in mid- June and fenvalerate applied in April were all highly effective in controlling leaf- miners. Diflubenzuron, permethrin, chlorpyrifos, and FMC 54800, all controlled leafminers. Aldicarb, a systemic insecticide, provided good control. Efficacy tests show that with proper timing, many materials effectively reduce leafminer populations. INTRODUCTION Reissig et al (1982) quantitatively measured the During 1980-84, gracillarid leafminer infesta- Cffects of the apple-blotch leafminer, tions in commercial apple, cherry, pear, and prune Phyllonorycter (Lithocolletis) crataegella orchards were reported from Washington, northern Oregon, and Idaho fruit growing regions. In 1980, D. R. Davis?, and D. M. Weisman® identified the leafminer species found in Washington State as Phyllonorycter elmaella Doganlar and Mutuura. Since 1980, P. elmaella, the western spotted ten- tiform leafminer (WSTLM) has reached outbreak numbers in some areas of the Pacific Northwest. Doganlar and Mutuura (1980) found P. elmaella on unsprayed apple in 1976 and 1977 in the Van- couver, B.C. area. They stated that this was the same species recorded by Pottinger and LeRoux (1971) on apple in Oregon. A. F. Allred (unpublish- ed data) found P. elmaella infesting leaves in Utah orchards in 1977. Don Davis (unpublished data) tentatively identified the leafminer from the Provo area of Utah as P. elmaella. He also found that many leafminer populations in apple orchards in Utah were high for four seasons in a row, then declined. In eastern North America, severe tentiform leaf- miner infestations debilitate trees in several ways: by causing premature leaf fall, fruit ripening and fruit drop, reduced terminal growth and fruit size, and reduced fruit set for the following year (Kremer 1963, Pottinger and LeRoux 1971). ‘Department of Entomology, Washington State University, Ir- rigated Agriculture Research and Extension Center, Prosser, WA 99350. *D. R. Davis, Smithsonian Institution, Department of En- tomology, Natural Museum of History, Washington, D.C. 20560. °D. M. Weisman, USDA-ARS-NER, National Museum, Washington, D.C. 20560. (Clements), on McIntosh apple in New York, where more than two mines per leaf caused premature fruit drop during the current season and reduced fruit set and production in the following season. They also found that the spotted tentiform leaf- miner, (STLM) (P. blancardella (F.), had little ef- fect on growth or production of Idared or Rome Beauty cultivars during the first year of infestation, but reduced fruit set and production the following year. They stated that second generation larvae caused more damage than the first generation larvae. At present, we know very little about the effect of WSTLM infestations on tree growth and fruit pro- duction in the Pacific Northwest. In Washington, we have observed an average of nine mines per leaf on Red Delicious and Criterion apple at mid- season, and as many as 25 mines per leaf at the end of the growing season. A _ tentative economic threshold for Red Delicious in Washington is three mines per leaf during June-July. In Washington, growers apply a variety of insec- ticides for WSTLM, particularly in the post bloom period, but such treatments may well lead to in- creases in pest mite populations. The objectives of the study reported in this paper were to determine the efficacy of and timing for several insecticides for WSTLM and to monitor their effects on mite populations. MATERIALS AND METHODS 1983 Experiments In 1983, we evaluated 10 foliar and five systemic pesticides for control of WSTLM populations. We 8 J. ENTOMOL. SOC. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 used plots at three sites. One plot was established near Kennewick, WA, in an orchard with 7-year- old Criterion apple trees in a 3.0 x 6.1 m spacing. A second test block, established near Prosser, WA, was in an orchard with 4-year-old Red Delicious apple trees in a 3.0 x 5.5 m spacing. A third test block was established near Pasco, WA, in an or- chard with 4-year-old Red Delicious apple trees in a 3.0 x 5.5 m spacing. All orchards were irrigated by sprinkler and had grass cover crops. The infestation of WSTLM varied from 2-15 mines per leaf when evaluated in the fall of 1982. Foliar applications were tested at Kennewick and Prosser; plot size ranged from 0.2 to 0.8 ha and insecticides were ap- plied with an airblast sprayer at “pink stage”, in mid June or at both times. Systemic materials were evaluated at Pasco; replicated plots composed of 5 trees were used and the systemic insecticides were applied to the soil during late May. In the test plots we evaluated populations of WSTLM, active stages of apple rust mite, (Aculus schlectendali Nalepa), European red _ mite, (Panonychus ulmi Koch), McDaniel spider mite, (Tetranychus mcdanieli McGregor), and _ the western orchard predator mite, (Typhlodromus oc- cidentalis Nesbitt). During the season at Kennewick and Prosser, 10 leaves were collected weekly or biweekly at random from fruiting clusters from each of the same 10 trees at the center of each plot. At Pasco, leaves from the fruiting cluster were ran- domly collected from the center tree in each plot. Individual leaves were examined under a dissecting microscope. For insecticide efficacy studies, the total number of mines per leaf was counted. Also, on each leaf we counted the total number of active stages of the mite species mentioned above. At Kennewick, “pink stage” applications were applied March 31 and the post-bloom applications on June 4. In all applications, 2.377 kl/ha of water was applied. Materials, rates and timing are given in Table 1. At Prosser, applications at “pink stage” were applied on April 6 using 0,561 kl/ha of water. Applications at “post-bloom” were applied on June 17 using 0.935 kl/ha of water. In addition, aldicarb was broadcast within the dripline around in- dividual trees, worked into the soil, and water ap- plied. Materials, rates, and timing are given in Table 2. At Pasco, systemic pesticides were applied to the soil during late May. Aldicarb was broadcast in a 1.4 m band, .152 m from the tree on both sides of the row and rototilled 0.76 m deep; carbofuran was broadcast and ethoprop was sprayed in a .92 m band, .152 m from the tree on both sides of the row and rototilled; phenamiphos was sprayed in a .152 m continuous band in the row; oxamyl was sprayed in two 2.5 m bands at 1.22 m from the tree on both sides. Rates are given in Table 3. TABLE 1. Mean number of WSTLM miners per leaf in plots after foliar applications, sampled on two dates. Kennewick, WA, 1983. Material! Applied Check 2s Oxamy 12 March Carbosulfan March June Chlorpyrifos March Chlorpyrifos June Permethrin March Dif lubenzuron March & June Methomy 1 March & June Cypermethrin March & June Oxamy | June Oxamy | March 1 Means within a column followed by the different (P = 0.05) DMRT. Rate (kg Al/ha Heron OOF HP HN + Sampling Dates 8 10s = 3.2 a 19 Owed 1st 1.24 b 15.4 b 240 0.98" be Zee 2 680 0.8 bcd 6.6 d 680 0.7 bed 6.0 de 225 0.4 de 4.0 if 561 O.1 ei f 016 0.0 eo 3.9 if 111 0.08 e200 f 121 0.03 e 4.9 d f Ze 0.02 e 2.5 f same letter are not significantly 2 Next to cherry orchard heavily infested with WSTLM. J. ENTOMOL. SOc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 9 TABLE 2. Mean number of WSTLM mines per leaf after foliar applications, sampled on two dates. Pro- sser, WA, 1983. Sampling Dates Material? Applied Rate (Kg Al/ha) VAS 10/26 Check = == 1.9 at Lad a Formetanate June Peak 0.68 b pe Chlorpyrifos June 1.680 Uz55> ibe es Endosul fan June 3.364 O.51 ca S20. 7G Chlorpyrifos April 1.680 0.44 cd doo ed Formetanate April dizi 0.36 d 5.4 cd Chlorpyrifos April & June 1.680 Os) e Jo... cae Endosul fan April 3.364 ees e 4.5 cdef Oxamy 1 April BERG iva Os, e 4.0 ef Formetanate April & June ieizt 0.14 2) 4.2 def Fenvalerate April 2336 0.06 a 4.0 ef Endosul fan April & June 3.364 0.06 e 33 ef Oxamy | June a ieee baa 0.01 e Dao if Aldicarb April 4.486 aa 1.4 f 1 different (P = 0.05) DMRT. Means within a column followed by the same letter are not significantly TABLE 3. Means numberof WSTLM mines per leaf in systemic insecticide plots, treated in late May and sampled on two dates. Pasco, WA, 1983. Material! Ethoprop Check Phenamiphos Carbofuran Phenamiphos Ethoprop Aldicarb Oxamy | Ethoprop Oxamy | Aldicarb Ethoprop + Aldicarb 1 Rate (kg AlI/ha) 13.457 Beo72 6.728 + 4.486 cantly different (P = 0.05) DMRT. Sampling Dates 8/16 .l6 a .l6 a .14 ab .14 ab .12 abc nA. abe ~L2 abc ovo ot OO O88 oF) oO) Oo 9/29 ee 42 38 36 oO 26 220 . 06 298 E . 06 1,00 . 88 )6 a ab bc Means within a column followed by the same letter are not signifi- 10 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 1984 Experiment In 1984, we evaluated five foliar insecticides at two application dates and one systemic pesticide at one site near Moxee. Plots were established in an or- chard with 5-year-old Red Delicious apple trees in a 3.0 x 6.1 m spacing. Each plot consisted of 16 trees and each plot was replicated twice in a randomized complete block design. Foliar applications of insec- ticides were with a handgun to the point of runoff; “pink stage” applications were done in April and mid-summer. The systemic tested, aldicarb, was worked into the soil at four locations within the dripline of individual trees and was followed by water application. Populations of WSTLM and ac- tive stages of the mites listed above were evaluated by examining with a stereomicroscope, 10 leaves collected at random from fruiting clusters from each of the same four center trees per plot. RESULTS AND DISCUSSION Results of the insecticide tests are given in Tables 1 through 4. All materials provided some control of leafminer populations, especially during the June- July period, although there were significant dif- ferences in the treatments. At Kennewick, one of the two plots treated at “pink stage” with oxamy]l, was adjacent to a cherry orchard heavily infested with WSTLM and adults apparently moved into our plot, resulting in the high infestation. In 1983, in general, applications at “pink stage” provided control as good as, or better than, applications in June and two applications were better than one. In 1984, insecticides, except for permethrin, applied at “pink stage” did not provide as good control as mid- summer applications and two insecticide applica- tions were again better than one. In the eastern USA, methomy] and oxamy] effec- tively control STLM (P. blancardella (F.)). But these carbamates can also precipitate spider mite outbreaks, be detrimental to predator mites and precipitate outbreaks of insects such as the woolly apple aphid (Leeper 1981). Baird and Homan (1983) state that methomyl! may disrupt integrated mite control efforts. In 1983, in the plots at all three of our test sites, populations of all mite species were low and spider mites did not reach damaging levels. TABLE 4. Mean number of WSTLM mines, European red mites (ERM), and McDaniel mites, (MCM) per leaf on September 13, 1984, Moxee, WA. Rate Material! Applied (kg Al/ha Check a a Dif lubenzuron April G56 Dif lubenzuron April 0.28 Dif lubenzuron April 0.21 FMC 54800 April 0.09 Thiodicarb July 0.84 Thiodicarb April 0.84 Thiodicarb April & July 0.84 Dif lubenzuron July 0.28 Diflubenzuron April & July O56 Permethrin April 0.225 Chlorpyrifos July 1.680 Diflubenzuron April & July 0:21 Diflubenzuron April & July 0.28 Dif lubenzuron July 0.21 Dif lubenzuron July 0.56 FMC 54800 July 0.09 FMC 54800 April & July 0.09 Aldicarb May 4.486 Mean No. Mean No. Mean No. Mines/Leaf ERM/Leaf MCM/Leaf 2.2 4a 0.2 a 0.04 a 2.0 ab 0.2 a 0 a 2.0 ab 0.3 a 0.06 a 1.8 ab 0.2 a 0.01 a 1.6 abc 0.4 a 0.08 a 1.3 abcd 0.6 a 0.0l a 1.1 abcd 0.6 a 0.08 a 0.9 abcd 0.6 a O.08\ca 0.8 bed 0.2 a 0 a 0.7 bed 0.6 a 0 a 0.7 bcd 0-3-4 0.6 b 0.6 bcd 4.1 ab 0.4 cd 0.3 a 0 a Oa3 cd 1.6 a 0 a 033 cd 0.4 a 0 a OZ cd ileal 0.09 a 0.08 7.4 ~»be 0.2 ab 0.05 1055 Cc 13 (e 0.03 15a 0.2..a 1 Mean within a column followed by the same letter are not significantly different (P=0.05) DMRT. J. ENTOMOL. Soc. BriT. COLUMBIA 82 (1985), DEc. 31, 1985 ll However, in the fall of 1984, following the 1984 tests, populations of European red mites and McDaniel mites were significantly higher in plots treated during the summer with FMC 58400 than in the check. We found the eulophid parasite, Pnigalio maculipes Crawford, parasitizing WSTLM larvae infesting apple and cherry leaves in central Washington. Weires et al. (1982) demonstrated that several insecticides used in eastern USA are toxic to a braconid, Apanteles ornigis Weed, which is a principal parasite of STLM. Dutcher and Howitt (1978) found parasitism by all eulophid parasites was significantly lower in all insecticide plots than in the control plots in Michigan apple orchards. During 1981-84 many Washington fruit growers applied various insecticides for control of WSTLM and these applications might have reduced parasite populations. WSTLM may continue to spread and infest fruit growing areas of British Columbia which includes fairly large numbers of McIntosh apples. In eastern New York, McIntosh appears to be quite susceptible to leafminer damage (Reissig et al. 1982). ACKNOWLEDGMENT The authors gratefully acknowledge Harold F. Madsen, Hugh W. Homan, Robert W. Zwick, Jay C. Maitlen and Eric E. Halfhill for their many sug- gestions and review of the manuscript. We also thank the Yakima Valley Fieldmen’s Association for their support. REFERENCES Baird, C. R. and H. W. Homan. 1983. Tentiform leafminer, a new Idaho pest, Univ. of Idaho. Current In- fo. Series No. 697: 1-4. Doganlar, M. and A. Mutuura. 1980. A new species of Phyllonorycter Hbn. (= Lithocolletis Hbn.) (Lepidoptera: Gracilariidae) from western North America. Can. Entomol. 112: 311-13. Dutcher, J. D. and A. J. Howitt. 1978. Bionomics and control of Lithocolletis blancardella in Michigan. J. Econ. Entomol. 71: 736-83. Kremer, F. W. 1963. Major leafminer species occurring in the south Tirolean fruit-farming region and their control Pflanzenschutz-Nachr. 16: 1-16. Leeper, J. R. 1981. Extension based tree and small fruit insect pest management strategies. New York State Exp. Station. Geneva Bull. No. 88: 1-18. Pottinger, P. R. and E. J. LeRoux. 1971. The biology and dynamics of Lithocolletis blancardella (Lepidoptera: Gracilariidae) on apple in Quebec. Mem. Ent. Soc. Can. 77. 437 pp. Reissig, W. H., R. W. Weires, and C. G. Forshey. 1982. Effects of Gracillariid leafminers on apple tree growth and production. Environ. Entomol. 11: 958-963. Weires, R. W., J. R. Leeper, W. H. Reissig, and S. E. Lienk. 1982. Toxicity of several insecticides to the spotted tentiform leafminer (Lepidoptera: Gracillariidae) and its parasite, Apanteles orgnigis. J. Econ. Entomol. 75: 680-684. THIS PAPER REPORTS THE RESULTS OF RESEARCH ONLY. MENTION OF A COMMERCIAL PRODUCT DOES NOT CON- STITUTE A RECOMMENDATION FOR USE BY THE U.S. DEPARTMENT OF AGRICULTURE, NOR DOES IT IMPLY REGISTRA- TION UNDER FIFRA AS AMENDED. 12 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 ENDEMIC ALEYRODIDAE (HOMOPTERA) AND THEIR PARASITES (HYMENOPTERA) ON SOUTHERN VANCOUVER ISLAND, BRITISH COLUMBIA DAVID R. GILLESPIE Agriculture Canada Saanichton Research And Plant Quarantine Station 8801 East Saanich Road Sidney, B.C. V8L 1H3 Contribution #275, Agriculture Canada Saanichton Research And Plant Quarantine Station ABSTRACT Four species of whitefly (Trialeurodes vaporariorum (Westwood), T. merlini (Bemis), Aleyrodes spiraeoides Quaint., and Aleyrodes sp. A) were collected on native plants on southern Vancouver Island. Three species of parasite (Encarsia sp. (?formosa Gah.), Euderomophale sp. and Amitus arcturus Whitt.) were reared from these species. The possibility of using these parasites for biological control of T. vaporariorum in greenhouses is briefly discussed. INTRODUCTION Biological control of the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Homoptera: Aleyrodidae) by Encarsia formosa (Hymenoptera: Aphelinidae) is routinely used by many greenhouse tomato growers in different parts of the world. The use of this control practice is threatened by the introduction of cold-hardy tomato varieties (Vet, van Lenteren and Woets 1980). These varieties should produce marketable crops at 18°C day and 7°C night temperatures (van Lenteren and Van der Schaal 1981) and provide considerable savings of energy costs to growers. As E. formosa does not control T. vaporariorum below 18°C (Burnett 1949), growers may have to return to a heavy reliance on traditional control measures. A solution to the problem may be the use of alter- native parasites of T. vaporariorum which have more moderate temperature requirements (van Lenteren and van der Schaal 1981). A source of such parasites is populations of aleyrodid species endemic to northern latitudes. This paper presents the results of a survey of whitefly species and their parasites on selected host plants in the southern Vancouver Island region of British Columbia, Canada. MATERIALS AND METHODS Species of whitefly and their parasites were col- lected from Arbutus menziesii Pursh. (arbutus), Lonicera hispidula (Lindl.) Doug. (purple honeysuckle), Rubus ursinus Cham. & Schl. (trail- ing blackberry), Rubus spectabilis Pursh. (salmon- berry) and various cultivated varieties of Fragaria sp. (strawberry) at selected sites on the Saanich Peninsula, B.C. at bi-weekly intervals from 6 May to 12 Sept., 1983. Sites and host plants were selected on the basis of preliminary surveys that determined on which host plants and at which loca- tions whitefly immatures could be found relatively easily. Except for the strawberry site which was a small test plot located at the Saanichton Research and Plant Quarantine Station, the sites were oc- cupied mostly by natural vegetation. Twenty-five leaves of each host were collected and leaves bearing whitefly puparia or parasitized scale were held for emergence in plastic 1 L con- tainers covered with fine screen. Moist paper towelling was placed in the bottom as a humidity source. Whitefly and parasite emergence was recorded daily. Estimates of percent parasitism were obtained by counting puparia from which either hosts or parasites had emerged in the field, on dates when emergence of the generation of whitefly had been completed. All sites were examined for overwintering stages of whitefly in the winters of 1982/83 and 1983/84. RESULTS Whitefly species Four species of whitefly were collected on the five plant hosts. Trialeurodes vaporariorum was found on A. menziesii (arbutus), L. hispidula (purple honeysuckle) and R. ursinus (salmonberry). Puparia were present from 6 May to 20 June and adults began emerging on 10 May. Nymphs and puparia occurred on the foliage from the previous year. Adults were observed on new foliage of all three hosts from 10 May to 18 Aug., but no eggs were found and no subsequent generations occurred. Eggs of T. vaporariorum were found on leaves of trailing blackberry and purple honeysuckle in December and January of 1982-83, suggesting either that T. vaporariorum adults have an aestiva- tion period on these hosts, or that they use alter- native hosts during the summer months. No stages of T. vaporariorum were found in extensive sear- ches of other plants in the vicinity of the collection sites. On arbutus, puparial densities ranged from 0.70 to 3.18 puparia per leaf; on purple J. ENTOMOL. Soc. Brit. CoLumBiA 82 (1985), DEc. 31, 1985 13 honeysuckle, from 0.04 to 1.31; and on R. ursinus (trailing blackberry) from 0.10 to 8.50 puparia per leaf. Trialeurodes merlini (Bemis) was rare on ar- butus. Twenty-three puparia were collected on May 13 and these emerged from 18-20 May. Other- wise, T. merlini was not collected. Aleyrodes spiraeoides Quaint. was collected from strawberry and was also observed on a number of hosts: potato, iris, rose and a weed, Lactuca muralis. Adults were observed continuously on strawberry from Dec. 1982 to Dec. 1983. Eggs were present from 10 May to 15 Aug., and puparia from 20 June to 12 Sept. Adults overwintered on lower leaves of strawberry as well as on those of native broad-leafed evergreens, e.g. arbutus and Gaultheria shallon Pursh (salal). On strawberry, puparial densities ranged from 0.04 to 1.24 puparia per trifoliate leaf. An apparently undescribed species of Aleyrodes (Aleyrodes sp. A) was collected from R. spectabilis (salmonberry) and was also observed on Osmaronia cerasiformis (T. & G.) Greene (Indian plum). Adults were present throughout the year. Eggs were present from 6 May to 29 Aug. and puparia from 20 June to 12 Sept. Adults overwintered on lower leaves of arbutus and salal. Densities of puparia on salmonberry ranged from 1.01 to 17.20 puparia per leaf. Puparia of Aleyrodes sp. A and A. spiraeoides are indistinguishable (J. Martin’ pers comm.). Adults of the former species are light cream-colored throughout, whereas adults of the latter species are black on the head and abdomen. Also, Aleyrodes sp. A would not accept strawberry as a host and adults of A. spiraeoides did not accept either salmonberry or indian plum. Parasite species Three species of parasite were reared from out- door collections of whitefly puparia: Encarsia sp. (?formosa Gah.), (Hymenoptera: Aphelinidae), Euderomophale sp. (Hymenoptera: Eulophidae) and Amitus arcturus Whitt. (Hymenoptera: Platygasteridae). Overall, Encarsia sp. was the most abundant species (57 % of total), A. arcturus was next (36% of ‘Dept. of Entomology, British Museum of Natural History, Cromwell Road, London SW7 5BD. total) and Euderomophale sp. was least abundant (7% of total). On T. vaporariorum, A. arcturus was the most abundant parasite (50% of total), Encarsia sp. was next (40% of total) and Euderomophale sp. was the least abundant (10% of total). Euderomophale sp. was not represented in collec- tions of Aleyrodes sp. A although adults were observed on Indian plum leaves bearing scale of Aleyrodes sp. A. Percent parasitism of T. vaporariorum ranged from 6% to 29% on arbutus and from 14% to 20% on trailing blackberry. Percent parasitism of A. spiraeoides on strawberry was 52% and that of Aleyrodes sp. A. on salmonberry ranged from 18% to 50%. Encarsia sp. was the only parasite reared from A. spiraeoides. On Aleyrodes sp. A, Encarsia sp. was the most abundant parasite (97% of total) and A. arcturus made up the remainder. DISCUSSION As all three parasite species were reared from T. vaporariorum collected outdoors in the late spring, when ambient temperatures ranged around 10°C., it may be assumed that they have some degree of cold-tolerance. Mound and Halsey (1978) record six species each of Amitus and Euderomophale as parasitic on Aleyrodidae in various parts of the world, but none parasitic on T. vaporariorum. Dowell (1979) credited A. hesperidum Silvestri with contributing to decline of populations of the whitef- ly, Aleurocanthus woglumi Ashby, in southern Florida. Further study will be required to deter- mine which of the parasite species would be useful in green houses for control of T. vaporariorum. En- carsia sp. would be the most desirable candidate because present rearing, handling, storage and ship- ping techniques could be used with little modification. ACKNOWLEDGMENTS I thank N. Williams and S. Hart for technical assistance, Mr. J. Martin (Dept. of Entomology, British Museum of Natural History) for identifica- tions of Aleyrodidae, and Dr. G. Gordh (Dept. of Entomology, University of California, Riverside) and Dr. L. Masner (Agriculture Canada, Biosystematics Research Institute, Ottawa) for identifications of Hymenoptera. REFERENCES Burnett, T. 1949. The effect of temperature on an insect host-parasite population. Ecology 30:113-134. Dowell, R. V. 1979. Synchrony and impact of Amitus hesperidum (Hym:Platygasteridae) on its host, Aleurocanthus woglumi (Hym: Aleyrodidae) in southern Florida. Entomophaga 24:221-227. Lenteren, J. C. van and van der Schaal, A. W. J. 1981. Temperature thresholds for oviposition of Encarsia formosa, E. tricolor and E. pergandiella in larvae of Trialeurodes vaporariorum. (in English) Med. fac. Landbouww. Rijks univ. Gent 46: 457-464. Mound, L. A. and Halsey, S. H. 1978. Whitefly of the World. A systematic catalogue of the Aleyrodidae (Homoptera) with host plant and natural enemy data. Chichester: British Museum (Natural History) and John Wiley and Sons. Vet, L. E. M.; van Lenteren, J. C. and Woets, J. 1980. The parasite-host relationship between Encarsia formosa (Hymenoptera:Aphelinidae) and Trialeurodes vaporariorum (Homoptera: Aleyrodidae). (in English) Z. Agnew. Ent. 90:26-51. 14 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 NATURAL ENEMIES OF MYZOCALLIS CORYLI (HOM.:APHIDIDAE) IN OREGON HAZELNUT ORCHARDS R. H. MESSING AND M. T. ALINIAZEE Departmet of Entomology, Oregon State University, Corvallis, Oregon ABSTRACT Fifty-five species of aphidophagous predators were found in a survey of the hazelnut orchards of western Oregon. Important predators of the filbert aphid, Myzocallis coryli (Goetze), include: Adalia bipunctata (L.), Cycloneda polita Csy. (Coleoptera: Coccinellidae); Deraeocoris brevis (Uhler) (Hemiptera: Miridae); and species of Hemerobius Chrysopidae). and Chrysopa (Neuroptera: Hemerobiidae and One parasitoid, Mesidiopsis sp. (Hymenoptera: Aphelinidae) was found to at- tack the aphid. In addition, one pathogenic fungus, Triplosporium fresenii (Nowakowski) Batko (Entomophthorales: Entomophthoraceae) was found to cause an epizootic in an orchard with a high aphid density. INTRODUCTION Myzocallis coryli (Goetze), the filbert aphid, is a serious pest of hazelnut (filbert), Corylus avellana (L.), orchards of North America. Recurring aphid outbreaks are experienced by commercial orchards, with population densities reaching as high as 500 aphids per leaf. Although the effects of such large aphid populations are not well documented, it is generally believed that aphid feeding causes reduc- tion in nut size and percent kernel fill. In addition, aphids secrete large quantities of honeydew which may cause leaf scorch, sooty mold growth, staining of nuts, and fouling of orchard equipment (AliNiazee, 1980). M. coryli is a monecious species, spending its en- tire life cycle on the filbert tree. It is the only aphid found on North American hazelnuts, and is con- sidered to be of European origin (Richards, 1968). Commercial hazelnut production in North America is concentrated in the Pacific Northwest, with the Willamette Valley of Oregon accounting for about 95% of production, with smaller acreages in Washington and British Columbia (Baron and Stebbins, 1978). Growers typically rely on one to three applications of insecticide annually to control the aphid. However, the aphid has developed populations resistant to carbaryl, the most com- monly used insecticide in hazelnut orchards (AliNiazee, 1983a). There is also indication of resistance against some commonly used organophosphate compounds (AliNiazee, un- published data), thus complicating the control pro- gram. Some growers are already encountering in- creasing difficulties with insecticidal control of M. coryli. A number of predacious insects are associated with the filbert aphid in western Oregon, and several of these have been presumed to be important in natural biological control of this pest (AliNiazee, 1980). However, the complex of aphidophagous in- sects has not been systematically examined. The present study was designed to determine the presence and abundance of aphidophagous predators in the hazelnut agro-ecosystem, and to provide information on their relative importance and synchrony with the filbert aphid. METHODS During 1980 and 1981 a total of twelve hazelnut orchards were surveyed for natural enemies of M. coryli. Orchards were chosen from the major hazelnut producing areas in northern, central, and southern portions of the Willamette Valley. Or- chard conditions ranged from intensively managed to essentially abandoned. In 1981, nine orchards were sampled a minimum of three times each (in April, June, and November). In addition, more detailed information was gathered by sampling three orchards near Corvallis once every week for six months, to determine the relative abundance and phenology of natural enemies. Sampling was conducted using the limb-tapping method of Lord (1949). Three limbs were sampled per tree on ten randomly chosen trees on each sam- ple date. In one orchard, a ten minute visual search per tree was used to supplement the limb-tapping method. Predator feeding behavior was observed by ex- amination of insects both in the field and under laboratory conditions. Predators were placed in petri dishes containing moistened filter paper and filbert leaves infested with the aphids. In some cases predators were reared from early instars to adults by providing fresh aphids and moisture every few days. Aphid mummies were held individually in small gelatin capsules until parasitoid emergence; spores of a pathogenic fungus were slide-mounted for identification. RESULTS AND DISCUSSION A list of aphidophagous predators collected dur- ing this study is presented in Table 1. This list in- cludes rarely encountered species and “incidentals” as well as those more abundant and widespread. A total of 55 predacious species from twelve insect families was found in the hazelnut system (Table 1). The most important predators are discussed below, by family: J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 15 TABLE 1. Predaceous insects associated with Myzocallis coryli in hazelnut orchards in Oregon. 1980-1981. COLEOPTERA Cantharidae: Podabrus pruinous Lec. Coccinellidae: Anatis rathvoni (Lec.) Adalia annectans Crotch Adalia bipunctata (L.) Adalia frigida Schn. Calvia duodecimmaculata Geb). Calvia quatuordecimgutta (L.) Chilocorus sp. Coccinella californica Mann Coccinella transversoguttata Brown Coccinella trifasciata subversa Lec. Coccinella trifasciata perplexa Muls. Coccinella unidecimpunctata L. Coccinella sp. Cycloneda polita Csy. Exochomus quadripustulatus (L.) Exochomus sp. Hippodamia convergens G. M. Hippodamia quinquesignata ambigua Lec. Hippodamia sinuata spuria Lec. Hippodamia sinuata disjuncta Timb. Mulsantina picta Rand Scymnus sp. DERMAPTERA Forficulidae: Forficula auricularia L. DIPTERA Syrphidae: Eupeodes volucris (O.S.) Metasyrphus fumipennis (Thomsen) Syrphus opinatar (O.S.) Syrphus ribesii (L.) or torbus (O.S.) Cecidomyiidae: A phidolestes sp. Coccinellidae Twenty-two species of coccinellids were collected in association with the filbert aphid, but only two, Adalia bipunctata (L.) and Cycloneda polita Casey, were consistently abundant in all orchards surveyed. Coccinella californica Mann., C. trifasciata LeC., and Hippodamia convergens G.M. were moderately abundant, while the remaining species were infrequent or rare. A. bipunctata adults were active in the orchards from April through October (see Table 2), and some localized aggregations were found as early as March 17. This suggests that at least part of the population may be overwintering in the orchards, as has been reported in Europe (Hodek, 1973). A. bipunctata’s life cycle was well synchronized with that of the filbert aphid, which generally hatches from over- wintering eggs during the first week in March. Predation during this early period (March-April), the “initiation phase” of aphid population growth, is more likely to contribute to substantial biological control than predation later in the season. Obrycki et al. (1983) have shown that A. bipunctata over- wintering adults in New York have a low post- HEMIPTERA Anthocoris antevolans White Orius tristicolor White Atractotomus sp. Campyloneura virgula (H.S.) Compsidolon salicellum (H.S.) Deraeocoris brevis (Uhler) Deraeocoris fasciolus Knight Diaphnocoris sp. Heterotoma meriopterum (Scop.) Lupus decolor (Fallen) Paraproba nigrinervis (V.D.) Phytocoris sp. A Phytocoris sp. B Pilophoris sp. Nabis alternatus Parshley Anthocoridae: Miridae: Nabidae: NEUROPTERA Chrysopa placita Banks Chrysopa nigricornis Burmeister Chrysopa rufilabris Burmeister Chrysopa carnea Steph. Chrysopidae: Hemerobius humulinus Linn. Hemerobius ovalis Carpenter Hemerobius pacificus Banks Hemerobius stigma Steph. Hemerobiidae: ORTHOPTERA Oecanthus nigricornis (Walker) Oecanthus niveus (DeGeer) Gryllidae: RAPHIDIOPTERA Raphidiidae: Agulla sp. diapause developmental threshold of 7°C., which explains the early season activity of this predator in the field. Populations of A. bipunctata in Oregon peaked in early July, with a second, smaller peak in October indicating a partial second generation. Aye (1962) also reported a second generation in Califor- nia. Obrycki et al. (1983) found two to three generations per year in New York. C. polita adults were found in large numbers in most orchards; however, they did not colonize until May, when aphids were already entering their “ex- ponential growth phase”. Thus, their impact on biological control seems less pronounced. A single population peak was noticed, which indicates a univoltine life cycle for this species. The three other coccinellids, C. trifasciata, C. californica, and H. convergens were frequently found in the orchards, but in much lower numbers than either A. bipunctata or C. polita. Moreover, they occur during the mid-season after a substantial increase in aphid populations had already occurred. Miridae: Of the twelve species of mirids collected, 16 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 TABLE 2. Mean number of predators per sample for three hazelnut orchards. Willamette Valley, Oregon, 1981. Species Life-stage April A. bipunctata Adult 2.4 Cc. polita Adult 0.9 C. trifasciata Adult 0.2 H. convergens Adult >) ro) a t 200 ‘ Pd 100 pe: 0 a 21 28 6 13 July T. urticae overwinters in protected locations in the hop yard, probably around the base of trellis poles or on the subterranean crown. When the plant grew up the strings in May and June, the mites had already emerged and were feeding on basal hop leaves and on various weeds. As the season progress- ed the mites moved higher on the plant, attaining the greatest percentage of the total mites/leaf in the 0.9-3.7 m height range (Fig. 2a-d). Late in the season (i.e., early to mid-August) the proportion of mites/leaf in the upper 3 to 2 of the plant increased (Fig. 2i-m). Since there were many more leaves and a higher number of mites/leaf in this section of the plant, a very large percentage of mites on the plant was found here. In late August and early September larger, orange deutogynes developed and initiated a downward migration along the main vines. Once at the bottom of the plant they did not move onto leaves but probably left the vine to find overwinter- ing sites. The large twospotted spider mite population in the apical regions of the plant is extremely difficult for hop growers to control. Since conventional tractor-drawn, air-blast sprayers cannot deliver n 2e-==P. humuli ama | urticae 23 ZO Aug. 27 63 10 t Diazinon Fig. 1. Population levels of Phorodon humuli and Tetranychus urticae during the hop growing season. 24 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 + - se 37.5 25 12.5 0 A. 21 June B. 24-25 June ©.28-30 June D.6-8 July E. 13-15 July F. 21-23 July G. 27-28 July [. 6 Aug. J. 10 Aug. K. 13 Aug. L. 16-17 Aug. M. 20 Aug. N. 24 Aug. O. 27 Aug. P. 30-31 Aug. Fig. 2. Combined data of 1968 and 1982 showing percent of total twospotted spider mites/leaf at six heights on hop plants, from 21 June-31 August. The figure is sequentially arranged so that the change in dispersion from the lower leaves early in the season to the upper leaves later in the season may be readily seen. J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 25 enough pesticide into the upper regions of the plant and _ aircraft-applied material cannot descent through the canopy to reach the middle and lower regions of the plant, systemic pesticides may prove to be an essential control strategy. Although disulfoton is currently registered at 0.89 kg a.i./ha, no systemic pesticide is currently registered at a high enough rate to effect satisfactory control of twospotted spider mites. However, several are cur- rently being evaluated for this use. ACKNOWLEDGEMENTS We would like to thank Drs. R. D. Akre, L. K. Tanigoshi, and R. S. Zack, Department of En- tomology, Washington State University, for critically reviewing this manuscript, and Ms. San- dra D. Sites for assistance with field work. REFERENCES Henderson, C. F. and H. V. McBurnie. 1943. Sampling techniques for determining populations of the citrus red mite and its predators. USDA Circ. 671. PRE-EMERGENCE INSECTICIDE APPLICATIONS FOR CONTROL OF THE MOUNTAIN PINE BEETLE, DENDROCTONUS PONDEROSAE (COLEOPTERA:SCOLYTIDAE).! M. G. FUCHS AND J. H. BORDEN? Centre for Pest Management Department of Biological Science Simon Fraser University Burnaby, B.C., Canada V5A 1S6 ABSTRACT An experiment was set up near Princeton, British Columbia to investigate the efficacy of carbaryl (Sevin SL) and chlorpyrifos and (Dursban 4E) at 1% and 2% a.i. in water, to prevent the successful emergence of mountain pine beetles, Den- droctonus ponderosae Hopkins, from infested lodgepole pines, Pinus contorta var. latifolia Engelmann. All treatments were effective in killing the emerging beetles outright. Mortality ranged from 83.3% for 1% Sevin to 94.9% for 2% Dursban, compared with 6.1% mortality of beetles emerging from water-treated control trees. Living emergent beetles from all treatments suffered >50 and >90% mor- tality after 1 and 5 days, respectively, compared with 5 and 10 days, respectively, for beetles from control treatments. INTRODUCTION Various insecticides applied to the bark of in- fested trees are effective in preventing or reducing the successful emergence of bark beetles. Examples are: lindane against the western pine beetle, Den- droctonus brevicomis LeConte (Swezey and Dahlsten 1983), and lindane, chlorpyrifos, fenitrothion (and several other insecticides) against the southern pine beetle, Dendroctonus frontalis Zimmerman (Brady et al. 1980; Jones et al. 1980). As lindane is in disfavor because of environmen- tal concerns, it was judged necessary to evaluate ad- ditional materials for remedial use on the mountain pine beetle, Dendroctonus ponderosae Hopkins. In- tegrated pest management using semiochemicals (Conn et al. 1983; Borden et al. 1983) and insec- ticides for the eradication of small infestations from lodgepole pine, Pinus contorta var. latifolia Engelmann is of particular concern. Toward this end, this paper describes the evaluation of 2 insec- ‘Research supported in part by the Science Council of British Columbia and the Natural Sciences and Engineering Research Council, Canada, Operating Grant No. A388]. *Send requests for reprints to J. H. Borden. ticides, Sevin SL° (carbaryl) and Dursban 4EF*‘ (chlorpyrifos). MATERIALS AND METHODS Thirty lodgepole pines infested by D. ponderosae in 1981 were selected in the spring of 1982 and in the Summers Creek area approximately 25 km NE of Princeton, B.C. The timber type and the ecological classification is uniform throughout the area. All trees were >26 cm diameter at breast height (dbh) (x = 32.3 cm) and the mean dbh’s bet- ween treatment groups did not differ significantly (F test, p>0.05). To minimize potential problems with insecticide drift and contamination, 6 replicates (trees) for each of 5 insecticide treatments were randomly chosen as same-treatment groups. The control group was located approximately 400 m away from the nearest insecticide-treated trees. On 6 July, 1982, the trees were sprayed to the drip point with 2-3 L of water or insecticide for- *Union Carbide Agricultural Products Company, Inc., Jackson- ville, Florida. ‘Dow Chemical of Canada Limited, Sarnia, Ontario. 26 J. ENTOMOL. Soc. Brit. COLUMBIA 82 (1985), Dec. 31, 1985 mulation in water. A backpack sprayer (Solo 425, Solo Kleinmotoren GMBH, Sindelfingen, FDR) was used, allowing coverage of the basal 3 m of the bole. The 5 treatments were: Sevin at 1% a.i., 2% Sevin, 1% Dursban, 2% Dursban, and water. On 8 July, prior to beetle emergence, all 30 trees were felled. The first 0.8 m of each tree above the 0.3 m high stump was cut and transported to a B.C. Forest Service fire suppression camp approximately 5 km E of Princeton. There they were bagged in muslin and kept in a shaded area. Emergent beetles were collected every 2-3 days. Dead beetles were counted; live or moribund beetles (those unable to move normally) were held at room temperature in petri dishes with moist filter paper and checked dai- ly for longevity. _ The data were transformed by logio (x+1) if necessary and subjected to analysis of variance and the Newman Keuls test. RESULTS AND DISCUSSION Emergence of D. ponderosae was first noted on 17 July. The first major peak of emergence occurred during a warm period from 23-29 July, 17-23 days after the insecticide treatment. Subsequent peaks of comparable magnitude occurred from 5-9 and 15-27 August and 31 August - 4 September. There were no geniteant differences in total emergence between treatment groups, despite the very low emergence rate of 309.3/m? from the logs treated with 2% Dursban (Table 1). A possible 100 | PERCENTAGE OF BEETLES SURVIVING 2 4 6 fumigant effect of Dursban may account for this low emergence. L. H. McMullen® found 2% Dursban to be as effective as or better than 1% Lin- dane and recommended its use to kill D. ponderosae brood under the bark. R. S. Hodgkinson® obtained similar results with 2.4% Dursban in diesel oil for the spruce beetle, Dendroctonus rufipennis Kirby. The most striking effects of the insecticide treatments were the significantly small numbers of healthy beetles that emerged, especially for 2% Dursban, and the significantly greater numbers of dead and moribund beetles for all treatments except 2% Dursban (Table 1). This apparent anomaly can be explained by the low numbers of emergent beetles from logs treated with 2% Dursban, and is offset by the fact that this treatment resulted in the highest percentage (94.9%) of dead and moribund emergent beetles. Beetles emerging alive from logs treated with 2% Dursban suffered 96.5% mortality after 24 h (Fig. 1). Beetles emerging from logs treated with 1% Dursban or Sevin at both concentrations sustained less, but still severe mortality (>50% after 24 h), while only 4.1% of beetles emerging from the con- trol logs were dead after 24 h. Over 90% of the beetles emerging alive from treated logs were dead ‘Unpublished report, 1980, Pacific Forest Research Centre, Vic- toria, B.C. ®*Internal Report PM-PG-2. 1983. B.C. Forest Service, Prince George, B.C. CONTROL #&——# ec SEVIN 2% s——a SEVIN 1% 4 A DURSBAN 2% e—e 60 DURSBAN 1% o——o 8 10 12 14 16 DAYS AFTER COLLECTION Fig. 1. Survival of D. ponderosae held at room temperature and 100% RH after emergence from logs sub- jected to various insecticide treatments. 27 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEC. 31, 1985 *a0ueTIPA JO STSATeue 09 JOTId (1 + x) OTHoT Aq poawsojssueszy ALAC LO’ > d £3892 ,STNey ueUMaN ‘fqUdTayJTpP ATJUROTYTUBTS Jou aze JaqqQaT owes ayy Aq PaMOTTOJ UWNTODS eB UTYZIM Sue aH 6°76 Ge L°6€€ + 8° LEC Ole Peele Pe Onn + G°IE qe 6°S62 * £°SS2 eB 9°6SE + €°60E %2 “J uegsing ; 8°88 q L°LOS ¥ 2°068 Gb’ Stl+-O°9tl q O°OL F# 2°tLl Q 9 tthh + COLL Re L°8LS # E°900L %L Sah UeGsaIng 8°S8 q O°2SS + 8°698 Gea lL OL Q 2°0G6¢2 + 2°G8E Ge E€°9GE + S° HSH PB 2°E€LS + 8° 666 %Z ‘1S UTAIS €°€8 q 9°SGS9 + 0°SL6 q +t LO¢e + L°2S2 Q €°H82 + G°98E Je YOM L6E + S°BES eP 6°LH8 + B°L22l %L STIS UTAIS ig eP 96 + OEL BP O°L1LS + O°9EOL PF 9°8L F L°SL BP CLL + LS eB 2°60S + O°6OLL (41972M) TOTQUOD % Te.O] : 2W/AuaTROH ° ON zu /PUNqT ION °ON 7u/pead Iaqunn 7u/pabsow3 Teq.O] qVUuOWJeOT] punqtaoW pue peoqg JIquN phaobeqe) yoej ut satqeeq JO 4S + X ‘soyeor[dey 9 = N ‘Z86I ‘'O'e “UOOUIIg IvaU “YVII_ SIOUIUING ‘S9o1} PaISafUl UO S}UIUTV91} BplOloas -UI 90U9810UI9-a1d yUSJFFIP BULMOT[OJ UOIPUOD IIay} pue aesorapuod *q UeSIOUIS Jo sIaqUINN *T ATAVL 28 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), Dec. 31, 1985 within 5 days, while >50% of those from control logs survived 5 or more days. Thus, Dursban 4E appears to be slightly more ef- fective than Sevin SL, but only at a concentration of no less than 2%. These encouraging results with water-based formulations indicate that a diluent such as diesel oil need not be transported to target areas that have an adequate source of nearby water. The effectiveness of both insecticides for remedial treatments (Table 1, Fig. 1), and their efficacy in preventing attack by Dendroctonus spp. (Hall et al. 1982; McCambridge 1982) suggests that they may reliably replace lindane for direct suppression of the mountain pine beetle in lodgepole pine. ACKNOWLEDGMENTS We thank the B.C. Forest Service, particularly Messers G. W. Cooper and T. E. Lacey for allow- ing us to carry out the field work and for supplying frequent assistance, L. J. Chong, T. Ebata and L. H. Graf for help in experimental setup and evalua- tion, G. J. R. Judd for assistance in statistical analysis, the Department of Biological Sciences, Simon Fraser University for financial assistance, and Dow Chemical of Canada Limited and Union Carbide Agricultural Products Company for donating the experimental pesticides. REFERENCES Borden, J. H., J. E. Conn, L. M. Friskie, B. E. Scott, L 1983. Semiochemicals for the mountain pine bee 7 . Chong, H. D. Pierce Jr. and A. C. Oehlschlager. e, Dendroctonus ponderosae, in British Columbia: baited tree studies. Can. J. For. Res. 13: 325-333. Brady, U. E., C. W. Berisford, T. L. Hall and J. S. Hamilton. 1980. Efficacy and persistence of chlor- pyrifos, chlorpyrifos-methyl, and lindane for preventive and remedial control of the southern pine beetle. J. Econ. Entomol. 73: 639-641. Conn, J. E., J. H. Borden, B. E. Scott, L. M. Friskie, H. D. Pierce Jr. and A. C. Oehlschlager. 1983. Semiochemicals for the mountain pine beetle, Dendroctonus ponderosae, in British Columbia: field trapping studies. Can. J. For. Res. 13: 320-324. Hall, R. W., P. J. Shea and M. I. Haverty. 1982. Effectiveness of carbaryl and chlorpyrifos for protecting ponderosa pine trees from attack by the western pine beetle (Coleoptera:Scolytidae). J. Econ. En- tomol. 75: 504-508. Jones, A. S., F. L. Hastings and C. J. Kislow. 1980. Evaluation of 12 insecticides for remedial efficacy against southern pine beetle adults. J. Econ. Entomol. 73: 736-738. McCambridge, W. F. 1982. Field tests of insecticides to protect ponderosa pine from the mountain pine beetle (Coleoptera:Scolytidae). J. Econ. Entomol. 75: 1080-1082. Swezey, S. L. and D. L. Dahlsten. 1983. Effects of remedial application of lindane on emergence of natural enemies of the western pine beetle, Dendroctonus brevicomis (Coleoptera:Scolytidae). Environ. En- tomol. 12: 210-214. J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 SOME EFFECTS OF PINE OIL ON MOUNTAIN PINE BEETLE (COLEOPTERA: SCOLYTIDAE) AT DIFFERENT POPULATION LEVELS L. H. McMULLEN AND L. SAFRANYIK Canadian Forestry Service Pacific Forestry Centre 506 West Burnside Road Victoria, B.C. V8Z 1M5 ABSTRACT Two formulations of pine oil (BBR2 and Norpine 65) were tested for effec- tiveness in preventing attacks by mountain pine beetle and reducing brood produc- ition at different population levels on lodgepole pine trees. Pheromone-baited trees sprayed with BBR2 had a lower attack intensity than baited check trees and a lower brood success than either baited check trees or baited trees sprayed with Norpine 65. Only at a low population level was attack intensity reduced by both pine oil treatments. The proportion of attacked trees within 10m of the treated trees was lower in low than in high populations but showed no difference among treatments. RESUME On a vérifié l’efficacité de deux préparations d’huile de pin (BBR2 et Norpine 65) pour prévenir les attaques des dendroctones du pin ponderosa et réduire la pro- duction d’une couvée chez les insectes a différents niveaux de population habitant des pins tordus. Avec le BBR2, l’intensité de l’attaque des arbres piégés avec des phéromones a été moins élevée que dans le cas des arbres témoins piégés, et les couvées ont été moins nombreuses que dans le cas des arbres témoins piégés ou des arbres piégés arrosés avec du Norpine 65. L’intensité de l’attaque a été réduite par les deux préparations a de faibles niveaux de population seulement. La proportion des arbres attaqués a 10 m de distance des arbres traités a été moindre a des faibles niveaux de population qu’a des niveaux élevés, mais l'emploi de l’une ou de |’autre 29 préparation n’a fait aucune diffét rence. INTRODUCTION Pine oil (Norpine 65!) has been demonstrated to be effective in preventing attack on treated and un- treated neighboring trees by three species of Den- droctonus bark beetles (Nijholt and McMullen 1980, Nijholt et al. 1981), and by ambrosia beetles on logs (Nijholt 1980). Another formulation of pine oil (BBR2?) appears to be effective also in preven- ting attack by mountain pine beetle, (D. ponderosae Hopk.), on lodgepole pine, Pinus con- torta Douglas, (Nijholt, personal communication). However, BBR2 in fibreboard pieces distributed on the ground at the rate of 50 ¢/ha (McMullen and Safranyik unpublished? 1983) or fastened on baited trees (Nijholt, personal communication) did not pierce attack on lodgepole pine by mountain pine eetle except in one location where population pressure might already have been low. This report describes a study in which both pine oils, BBR2 and Norpine 65‘, were used in locations with different beetle populations to compare their ‘Northwest Petrochemical Corp., Anacortes, Wash. *Safer Agro-chem. Ltd., Victoria, B.C. 3McMullen, L. H. and L. Safranyik. 1983. Effect of pine oil distributed in fibreboard on the ground for protecting lodgepole pine from mountain pine beetle attack. File Rpt. 2 pp, 1 table, 2 maps. Pacific Forest Research Centre, Victoria, B.C. ‘Similar to that used by Nijholt (1980) but with « and @ pinene removed. effectiveness in preventing attacks on treated and neighboring untreated lodgepole pine trees. MATERIALS AND METHODS The study was carried out in mature (80 yrs. +), predominantly pure lodgepole pine stands of poor to medium site quality in the Cariboo Forest Region. The beetle population in each stand was rated as high or low on the basis of general tree mor- tality within the area. The locations of each stand and its population rating were as follows. a) Alexis Lake Road, high population. b) Tsuh Lake, high population. c) Tyee lake, low population. At each location 27 trees were selected for treat- ment in three 3 x 3 Latin squares. Treatment trees were at least 20 m apart and had a dbh of at least 20 cm. On July 4 and 5, 1984, before the attack period, BBR2 and Norpine 65 oils were sprayed on the lower 3.5 m of the bole of the respective treat- ment trees at the rate of approximately 2 per tree (0.55 ¢/m* bark area) with a garden type pressure sprayer. The check treatment trees were left unsprayed. Each treatment tree was baited with 0.5 cc of trans-verbenol and 0.5 cc of myrcene in separate, size 00, BEEM® capsules. The treatment trees, as well as those trees within 10 m, were ex- amined for attack (entrance holes) between August 3 and 13 (Table 1), after the attack period. The 30 J. ENTOMOL. Soc. Brit. COLUMBIA 82 (1985), DEc. 31, 1985 TABLE 1. Effect of two pine oil formulations (Norpine 65 and BBR2) on attack and brood success by moun- tain pine beetle on pheromone-baited and adjacent! lodgepole pine trees in stands with different population levels. Population Treatment2/ Level Dbh (cm) x Sx Index High Norpine 65 31.1 1.3 3.6 BBR2 315,070 V2 3). Check 28:51 2a 3.6 All 30.1 0.7 3.4a4/ High Norpine 65 31.8 1.8 Sid BBR2 30.3 1.0 om Check S153) 92:6 248 All 7 ice) Wana Lie | 2.7a Low Norpine 65 38.4 3.3 0.0 BBR2 S77 250 0.0 Check S425 dec 138 All 36.8 2.5 0.6b 1Within 10 m of treatment trees. 29 trees/treatment/location. 35 galleries of each attacked tree examined. Treatment trees Mean Attack Mean No. galleries Adjacent!’ trees Number Mean Percentage with brood?/ >10cm dbh attacked 23 93 54 0.4 138 57 2.4 TL 49 pea 342 50a 3.4 101 Spt 2 144 46 353 136 39 27 381 46a - op 0 - 45 4 = 25 14 - 121 6b ‘Means of the same level in columns followed by different letters are significantly different, Student Newman Keul’s range test (P = < 05). number of attacks on each treatment tree was recorded in classes of 0, 1 to 5, 6 to 10, 11 to 15, and 16 or more, and indexed as 0, 1, 2, 3, and 4, respec- tively. To determine the impact of the pine oil on brood success, five galleries on each attacked treat- ment tree at the two locations with high population levels were examined for the presence of brood on 14 November. The indexed attack classes and the number of galleries with brood were transformed to (X + .375)°-5. Analysis of variance and Student Newman Keul’s range tests were used to compare means. Analysis of variance with arc-sine transfor- mation was made on the percentage of trees attack- ed within 10 m of treated trees. RESULTS AND DISCUSSION Of the 425 adjacent trees with a dbh greater than 20 cm, 49.6% were attacked, and of 419 trees with a dbh less than 20 cm, 16.0% were attacked. The indexed attack data showed a significant dif- ference (P<.05) among locations and treatments (Table 1). The trees in the two high population areas had higher indices than those in the low population area and BBR2 had a lower index than the check treatment. Analysis of individual loca- tions indicated that only at the low population loca- tion, where the check was higher than either pine oil treatment, was there a difference among treatments. Also, the percentage of attacked trees adjacent to the treated trees differed only among locations; the low population location had a smaller percentage of adjacent trees attacked. This result confirms the original population rating of the stand. Brood success for the BBR2 treatment was significantly lower (P<0.01) than either the Nor- pine 65 or check treatments (Table 1). These data suggest that where the beetle popula- tion pressure is high, pine oil will not effectively prevent attack on trees baited with trans-verbenol and myrcene, but it will be effective where popula- tions are low. The data do not support any real differences bet- ween BBR2 and Norpine 65 in prevention of attack but BBR2, unlike Norpine 65, did reduce the brood success in terms of the number of galleries with brood in treatment trees. A study is needed to determine if attacks on un- baited trees can be prevented. REFERENCES Nijholt, W. W., and L. H. McMullen. 1980. Pine oil prevents mountain pine beetle pine beetle attack on living lodgepole pine trees. Can. For. Serv. Bi-monthly Res. Notes 36: 1-2. Nijholt, W. W., L. H. McMullen, L. Safranyik. 1981. Pine oil protects living trees from attack by three bark beetle species, Dendroctonus spp. (Coleoptera: Scolytidae). Can. Ent. 113: 337-340. Nijholt, W. W. 1980. Pine oil and oleic acid delay and reduce attacks on logs by ambrosia beetles (Coleoptera: Scolytidae). Can. Ent. 112: 199-204. J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), Dec. 31, 1985 31 EARLY SEASON APPLE PEST MANAGEMENT: CONTROL OF TWO SPECIES OF SCALES (HOMO.:DIASPIDIDAE) AND BRUCE SPANWORM (LEP.:GEOMETRIDAE) WITH METHIDATHION!' N. P. D. ANGERILLI AND D. M. LOGAN Agriculture Canada, Research Station Summerland, British Columbia, VOH 1Z0 ABSTRACT The organophosphate insecticide, methidathion, proved to be more ef- ficacious for the control of San Jose scale (Quadraspidiotus perniciosus (Comstock)) and European fruit scale (Q. ostraeformis (Curtis)) than dormant oil when applied at the tight cluster stage of bud development. The compound also provided effec- tive control of Bruce spanworm (Operophtera bruceata (Hulst)) and did not cause excessive mortality of the predaceous mites responsible for the biological control of orchard phytophagous mites. Methidathion use could be integrated into existing or- chard pest management programs by using currently accepted sampling schemes for the above pest organisms to determine when thresholds requiring treatment have been exceeded. INTRODUCTION In British Columbia apple orchards, San Jose scale and European fruit scale are serious pests in view of the requirement of several overseas export markets for apples to be free of San Jose scale. On apple fruit, European fruit scale is almost in- distinguishable from San Jose scale and hand sorting to remove scale infested apples increases packaging costs that can best be reduced through improved control measures in the orchard. Currently recommended control procedures for San Jose scale involve applications of petroleum oils during the dormant period with later applications of the organophosphate diazinon for control of the flying males in order to disrupt mating (Downing and Logan 1977) and for control of summer crawlers. These procedures have inherent logistical and technical difficulties that cause them to be less than 100% effective. The oil sprays are difficult to apply because of adverse winter weather and because equipment limitations often prevent the complete tree coverage which is necessary for effec- tive scale control. In some years the males emerge during bloom when insect pollination is essential, which prohibits coordination of spray application with male emergence. The crawlers are very small and difficult to detect, thereby making the timing of spray applications difficult. Control of European fruit scale currently relies on the application of dormant oil only, as the males almost always emerge during bloom and emergence of crawlers extends over most of the summer which would therefore require repeated diazinon applications. The objectives of this project were to: 1. determine if the organophosphate, methidathion, could be used during the dormant period to control both species of scale; 1Contribution No. 621 , Research Station, Summerland. 2. determine if this single spray could replace all or any of the currently recommended sprays; 3. measure the effects of methidathion on predaceous mites in order to determine the potential impact of the compound on the integrated mite con- trol program; 4, measure the effects of methidathion on the ear- ly season bud-feeding Bruce spanworm. MATERIALS AND METHODS For all treatments using methidathion (S-(2,3- dihydro - 5 - methoxy-2-oxo-1,3,4-thiadiazol- 3- yl-methyl)-0,0-dimethyl-phosphorodithioate) the commercial 25 EC formulation (Supracide®) was used. Dormant oil used was Axis dormant spray oil (viscosity approximately 180-220). San Jose Scale. 1982 A commercial orchard in Osoyoos, B.C. con- sisting of mixed Red Delicious, Golden Delicious and Winesap apple trees, about 20-years-old and planted 6 x 6 m, was divided into 6 unequal-sized plots that each contained at least 6 trees heavily in- fested with San Jose scale (SJS). Red Delicious trees were used as much as possible but Winesaps were included as necessary. Two guard rows were left between each plot. Treatments were assigned ran- domly and aplied at the 15 mm green stage of bud development on the Red Delicious trees, using an air-blast sprayer calibrated to deliver 2247 L/ha. At harvest, 500 apples were sampled from each of the 6 designated trees/plot. Treatments and rates of ap- plication are shown in Table 1. 1984 The same orchard was used again with some operational differences. Only Red Delicious trees were used, treatments were applied during the tight cluster stage of Red Delicious bud development, and only 400 apples per tree were sampled at harvest. 32 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 TABLE 1. Effect of several treatments on incidence of San Jose scale on fruit at harvest in an Osoyoos, B.C. orchard. i eee a a a a EN ee eee I OP ONE Dr ern em et Rate/ha Mean Percent Infested Fruit Red Delicious Winesap Total a a Si oe eee Treatment 1982 Oil 90.0 L 14.04 - 14.04 a 1* Methidathion 53674 + oil 45.0 L 1.64 0.05 0.58 a2 Methidathion Le2 + oil 45.0 L 0.23 - Os23 a2 Methiadathion 5.6 L 210 - 2./0-a 2 Methidathion Pls 291 0.60 - 0.60 ar 2 Control no treatment 82.40 58.90 14.57 1984 Oil 90.0 L 2.61 ab* ¥ Methidathion 5.6 L + oil 45.0.4. 0.21 a Control no treatment 4.65 b *Means followed by the same letter are not significantly different(P 0.01, SNK) Means followed by the same number are not significantly different(P 0.05, SNK), the control treatment was not included in the analysis for 1982. **kMeans followed by the same: letter are not significantly different(P 0.05, SNK) European Fruit Scale. 1983 In a commercial orchard in Summerland, B.C. consisting of 70 to 80 year old standard McIntosh apple trees, 7 treatments (Table II) were applied to blocks of about 20 trees all heavily infested with European fruit scale (EFS). All treatments were ap- plied at the tight cluster stage of bud development using an air-blast sprayer as above. Control effec- tiveness was measured by harvesting 500 apples (or all of the apples) from 6 randomly selected trees in each block. 1984 In the same orchard, the same treatments and methods were used except that treatment block assignments were re-randomized. For all of the above tests, the harvest data (as per- cent infested fruit) were transformed to arcsine square root (x) and subjected to an analysis of variance. Differences between means were tested with either the Student-Newman-Keuls test (SNK) or Duncan’s Multiple Range test. Non-Target Organisms Phytophagous and predaceous mites were sampl- ed by taking 15 leaves from each of 6 trees per plot in both of the orchards during both years and pro- cessing them by standard leaf brushing techniques in the laboratory (Morgan et al. 1955). These samples were taken during the period when the numbers of European red mites (Panonychus ulmi Koch) were increasing or had peaked. One sample was taken/orchard/year. Predaceous Mite Mortality Tests In addition to the mite counts described, two tests were conducted to determine the impact of methidathion on predaceous mites. In 1983, a plan- ting of 23 year old Golden Delicious apples was used to test the time of application of methidathion on predator mortality. There were 3 plots for each treatment and 4 trees per plot in a completely ran- domized experimental design. Guard trees were left between treatment rows and one guard tree was left between adjacent plots. Treatments were applied with a hydraulic boom sprayer operating at 1035 kPa, 3.10 kmh and calibrated to deliver 24.8 L/min or 2247 L/ha. Methidathion was applied at a rate of 5.6 L/ha, and treatments were applied at the following stages of tree bud development; 15 mm green, tight cluster, pre-pink, pink and petal fall. Mites were sampled by taking 10 leaves/tree from each of the trees in each of the plots and processing them in the laboratory using standard leaf brushing J. ENTOMOL. SOc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 33 techniques. Three samples were taken: the first on 83.05.10, the second on 83.05.19 and the last on 83.06.03. In 1984 a similar experiment was conducted us- ing a block of 23 year old Red Delicious apple trees. In this experiment there were 5 trees/plot and samples were taken on 84.06.05 and 84.06.20 and processed as described. Bruce Spanworm In the same orchard used for the EFS trials in 1984, 25 bud clusters were taken from 6 randomly selected trees from each of the 7 treatment blocks. The clusters were then examined for the presence of live or dead spanworm larvae. Mean numbers of larvae varied between clusters, so an analysis of variance was performed on the percentage of dead larvae per cluster. Means were compared with Duncan’s Multiple Range Test and the Student- Newman-Keuls test. RESULTS AND DISCUSSION In 1982, because of large differences between scale infestation levels on the harvested apples from the control block and the remaining blocks, an analysis of variance was performed on the remain- ing blocks in addition to an analysis of variance of all treatments. When the treatments were con- sidered together (including the control) all were equally effective relative to the control (Table 1). Comparing treatments after the exclusion of the control block suggests that all of the methidathion treatments were equally effective and superior to the oil treatment. However, the oil treatment did not control SJS at a commercially acceptable level. It is for this reason that the additional malathion sprays are recommended. Methidathion at 5.6 L/ha combined with oil gave commercially acceptable control of SJS during both years of the study. The treatments in this study were applied under ideal weather conditions of little or no wind using a carefully calibrated sprayer. However, commercial growers are often not able to wait for ideal weather conditions and their sprayers may not always be ac- curately calibrated, conditions which result in poor or erratic spray coverage and scale control. SJS con- trol with methidathion is probably not so sensitive as oil treatment to application conditions. There were no significant differences between treatments in the number of phytoseiid mite predators found during the mid-summer peak of European red mite which occurred in significantly larger numbers only in the control block in 1982. No significant differences between treatments in either predaceous or phytophagous mites were found in 1984. Results of the EFS trials were similar in both years (Table 2). Oil applied by air-blast sprayer was not so effective for scale control as methidathion, whereas oil applied by hand-gun was equally effec- tive. The trees used in this experiment were very large and had very rough bark, both of which limit the effectiveness of spray coverage with an air-blast sprayer. Poor EFS control is probably a conse- quence of large numbers of the insect under flaking bark and on new growth in the tops of the trees. Oil TABLE 2. Effect of several treatments on incidence of European fruit scale on fruit at harvest in a Sum- merland, B.C. orchard. Treatment Rate/ha on i 90.0 2 oil - hand gun to drip methidathion 5. 6-1 + oil 45.001 methidathion dels 2 racks + oil 45.0 1 methidathion DG. al methidathion Re COnELOL no treatment Mean Percent Infested Fruit 1983 1984 1.13 ab! 6.15 a On20ea 3.12 db 0.52 a 1.82 b O.27 a aT es 1.27 ab 3.62 b 0.47 a 8207 ob DOA 9.23 a IMeans within columns followed by the same letter are not significantly different (P<0.05, SNK). 34 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), Dec. 31, 1985 applied in large quantities by hand-gun gives effec- tive coverage and acceptable control. Unfortunate- ly, the time commitment and inconvenience of hand-gun applications limit their use. Significantly better control of EFS without the stringent coverage requirements of oil can be achieved with methidathion. There were no significant differences between phytophagous or predaceous mite populations dur- ing either year of the study. The results of the predator mortality tests showed no significant difference between time of applica- tion of methidathion for the phytoseiid predator, Typhlodromus occidentalis (Nesbitt), in 1983 or for the stigmaeid predator, Zetzelli mali (Ewing) in 1984. Bruce spanworm larval mortality was significant- ly higher in trees treated with methidathion than in those receiving either no treatment or dormant oil (Table 3). Dormant oil does not control this insect. The level of control effected by methidathion at either rate, with or without oil would be commer- cially acceptable. Better control might have been realized, but a lengthy period of cool weather in- creased the spanworm hatching period, thus allow- ing survival of late hatching larvae. The current recommendation for Bruce Span- worm control is an application of an organophosphate pesticide at the pink bud stage. Previous work by McMullen (1973) indicated 90 to 100 percent control with such an application. Our results are comparable in terms of commercially ac- ceptable levels of control and we believe that the tight cluster methidathion application can replace the pink spray. Pest Management Recommendations The integration of the tight cluster methidathion spray into existing orchard pest management regimes could proceed as follows: 1. Harvest fruit samples and assess for incidence of SJS and EFS to determine the dormant period control measures. Based on previous experience, areas with high counts of SJS or in orchards with chronic EFS problems, this step could be omitted and a spray applied routinely at least every other year. Our results suggest that for SJS, the methidathion spray could replace the dormant oil spray, the petal fall spray for male mating disrup- tion, and the two summer crawler sprays, thus resulting in a considerable reduction in pesticide usage and control effort. Research is underway to clarify the relationship between pheromone and sticky trap captures of SJS males and eventual fruit infestation. A positive relationship would enable monitoring of the male population levels with traps and thus the efficacy of dormant control measures could be determined. If the measures were unsuc- cessful, summer crawler sprays could be applied us- ing the degree day timing model currently being developed. 2. Bruce spanworm control is an automatic benefit of the methidathion spray. However, in those orchards with no scale problem, but with ab- TABLE 3. Effect of several treatments on incidence of Bruce Spanworm in apple blossom clusters in a Sum- merland, B.C. orchard. Treatment Rate/ha oil 2 Or Oa oil - hand gun toldxip methidathion Sao + Gack 45.0. 2 methidathion Teo + oat : 4550 1 methidathion DiaiO ad: methidathion Lie 2 control no treatment Mean Larvae % Dead 11.00 acl 0.00 a2 £2567) b 1.52: 2 8.50 abc 35.98 b List be Sore OS. S233 abe 5355 Db So? va I9-238e 6.33 ac “Zona IMeans within columns followed by the same letter are not significantly different (Duncan's Multiple Range Test, P<0.05). Means within columns followed by the same letter are not significantly different (Newman-Keuls test, P<0.01). J. ENTOMOL. Soc. BriT. COLUMBIA 82 (1985), DEc. 31, 1985 35 normally high spanworm populations, the methidathion spray could prove to be more useful than the currently recommended pink spray as it will also control some leafroller species (H. Madsen, personal communication). Work is currently in pro- gress to measure the relationship between males captured in pheromone traps in the fall and larval populations in the spring. This information could also be used to determine the need for spring control measures. 3. Our experiments suggest that methidathion ap- plied at the recommended rate of 5.6 1/ha does not cause significant predaceous mite mortality. This observation will require further investigation in other locations and subsequent years. 4. There is some evidence that methidathion ap- plied at tight cluster can have detrimental effects on insect pollinators if dandelions on the orchard floor or adjacent deciduous stone fruit trees are in bloom. Cultural practices may need modification to over- come this problem. ACKNOWLEDGMENTS We thank Lynn Brochu, Linda Dale, Frances FitzGibbon, Casey Jong and Brian Thair for technical assistance. We are grateful to John Mateus and Frank and Jean Lauer for permission to work in their orchards. REFERENCES Downing, R. S. and D. M. Logan. 1977. A new approach to San Jose scale control (Hemiptera: Diaspi- didae). Can. Ent. 109: 1249-1252. McMullen, R. D. 1973. The occurrence and control of the Bruce Spanworm in the Okanagan Valley, 1972. J. Ent. Soc. B.C. 70: 8-10. COMPARISON OF HONEY BEE QUEENS OVERWINTERED INDIVIDUALLY AND IN GROUPS STEPHEN R. MITCHELL', DANIELLA BATES?, MARK L. WINSTON!', AND DOUGLAS M. MCCUTCHEON? SUMMARY Productivity of honey bee queens, as measured by area of sealed worker brood and net weight of colonies, was generally higher with queens over- wintered in 2-frame nuclei, than with queens over- wintered in a group. Poor acceptance and supercedure of group overwintered queens suggest that this method of storage is not yet acceptable for commercial use. Survival of the nucleus queens was low in outdoor 2-frame units during the winter, but improved with an indoor system. Overwintering queens indoors in 2-frame nuclei and outdoors in 3-5 frame nuclei with supplemental feeding of car- bohydrate in late winter should provide a source of queens which could partially fulfill market demands in spring. INTRODUCTION Two systems of bee management are commonly employed in the cold beekeeping regions of Canada. Traditionally, beekeepers destroy all bees in the fall after removing honey, and renew their apiaries in the spring with imported packages containing 0.9-1.8 kg of worker bees and a queen. Increasingly however, beekeepers are overwintering a portion of their colonies and reducing the need to import packages. Nevertheless, large numbers of packages are still imported annually from the United States; in 1982, 350,000 packages valued at $10 million were imported (Winston 1983). Recognition of impending threats to North American apiculture from two parasitic mites of the ‘Department of Biological Sciences, Simon Fraser University, Burnaby, B.C. V5A 1S6. *B.C. Ministry of Agriculture and Food, 32916 Marshall Road, Abbotsford, B.C. V2S 1K2. honey bee and from Africanized bees moving nor- thward from Latin America, has resulted in the establishment of research programs on queen breeding (Corner 1977) and package bees (Winston 1983) in British Columbia. The presence of one of these mite parasites, Acarapis woodi (Rennie), was discovered in some of the package and queen pro- ducing regions of the southern United States in 1984, and has resulted in quarantines and import restrictions being imposed on the affected areas. A ban on importations of packages from the United States would create considerable hardship for Canadian beekeepers, since New Zealand is the only other country from which bees may be imported, and it is only a minor source of packages and queens (Canadian Honey Council 1982). The feasibility of producing package bees at competitive volumes in western Canada was first demonstrated by Pankiw and Corner (1970), and is now the subject of extensive research in British Col- umbia (Winston 1983; McCutcheon 1984). Development of a package bee industry would be facilitated by successful overwintering of large numbers of queens, since spring-reared queens may not be available early enough to meet the April deadlines necessary for commercial Canadian beekeeping. This study was started to investigate various methods of overwintering queens. In the study, queens were overwintered either in a 2-frame nucleus (small populations of worker bees on 2 frames) or in a mass holding facility, as describ- ed by Harp (1969). In the nuclei, single queens are free to move over the combs; in the Harp system, many queens are confined in special compartments on a modified frame. In both systems, the queens may lay eggs. An evaluation of queens overwintered by these two methods was undertaken in April 1983. 36 J. ENTOMOL. SOc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 METHODS Mated Italian honey bee queens, Apis mellifera ligustica Spin., which had been reared by the Ministry of Agriculture and Food in 1982, were established in colonies at Abbotsford, B.C. in late October. Eighteen queens were installed in a strong 20-frame colony outdoors according to the method described by Harp (1969). In brief, queens were placed singly in adjoining 4 cm x 4 cm wooden com- partments on a comb (9 on each side of the frame). Hive bees had access to the queens through queen excluder material covering the compartments. The colony was gorged with approximately one liter of honey one-half hour before the queens were in- troduced. An empty comb was placed on either side of the compartment frame, serving as storage space for sugar syrup, medicated with Fumidil B and sulphathiazole. Nine liters of this syrup (2 parts sugar; 1 part water) were fed in October, 1982. In January and February 1983, baker’s fondant icing sugar and pollen supplement patties were fed to the hive. One frame of brood from the support colony was placed next to the queens every 10-14 days. During March and April, two frames of brood were taken out of the support colony and placed next to the queens at 2-week intervals. Frames of pollen or pollen supplement patties were added every week. In addition, 9 L of sugar syrup were fed to the colony. On 3 November 1982, 68 queens were placed singly in 2-frame nuclei which were kept either in a 10°C building (32 nuclei) or outdoors in a long row (36 nuclei). The nuclei were derived from the parti- tion of a standard Langstroth hive body, resulting in 4 nuclei per box. Indoor nuclei had 2.54 cm of styrofoam insulation on top, while those outdoors were insultated with styrofoam on the top and sides and then wrapped with roofing paper. Queens from the Harp overwinterig system were caged and transferred to a queenright colony on 12 April 1983. To evaluate the Harp and nucleus queens, 26 packages of 0.9 kg (2 1b.) each were pro- duced at an apiary in Fort Langley, B.C., on 14 April. Six Harp queens, 10 nucleus queens, and 10 spring-produced queens imported from California were introduced to the packages in mailing cages, one queen per package. Syrup (1 part sugar: 1 part we) containing Fumidil B was supplied in stan- dard feed cans. In order to simulate the usual inter- val between package production and hiving, all packages were held in a cool basement for 48 hours. The packages were then hived at an apiary near Aldergrove, B.C., in standard Langstroth hive bodies containing 10 frames of foundation. Colonies were arranged randomly and each received 4.5 L of syrup (2 parts sugar: 1 part water). Between the time of installation and early June, each colony received an additional 12 L of syrup. A second hive body containing 10 frames of foundation was added to each colony when there were enough bees to cover 8 frames in the original box. The surface areas of comb occupied by sealed worker brood, honey and syrup, and pollen were determined on 10 May, 30 May, 20 June, 15 July, and 5 August, 1983. An 800 cm? plexiglass plate scored in 25 cm? units was used to measure the areas to the nearest 10 cm?. Colonies were also weighed on the measuring dates; net colony weight was calculated as the total colony weight minus weight of empty equipment. By 4 August, only one Harp queen was still alive and data for this single colony were not included in the analysis. Data were analyzed using a one-way ANOVA (SPSS-X). Further overwintering trials were undertaken in 1983. Forty-eight Italian queens imported from Texas were put in a populous 20-frame colony on 25 October, using the Harp system as previously described. Bees in the top super were gorged with honey poured on the top bars, the frame holding 48 queens was inserted in the center of that super, and more honey was poured on the top bars. The hive was wrapped with roofing paper for insulation in January 1984. On 5 and 25 February, 2 frames of brood from a support colony were added. On the first date, the colony also received syrup medicated with Fumidil B. On 25 February, syrup containing Fumidil B and Terramycin, and a_ pollen supplement patty were added to the colony. Medicated syrup was again given to the colony on 11 March. RESULTS Queen overwintering 1982-1983 From October 1982 until mid-April 1983, the Harp bank system suffered a 28% queen loss. Sealed brood was present in each compartment containing a live queen. However, when 10 Harp queens were placed in individual cages and introduced to a new queen bank in April, six died within 48 hours. The total overwintering loss of nucleus queens was 53%; of the 68 queens introduced on 3 November, 36 were alive on 22 March. Only 33% of the nucleus queens survived outdoors; but 75% of indoor-wintered nucleus queens survived until April. Queen overwintering 1983-1984 There was an initial loss of 9 queens between 18 October and 21 November 1983. The remaining 39 queens had sealed brood at 5 February when two frames of brood were added. Twenty-seven queens were alive on 25 February when brood was again added to the colony, but there was a subsequent decrease to 10 queens by 11 March. Queen evaluation 1983 During the course of the evaluation, queen supercedure occurred with 2 of the 10 California queens, 2 of the 10 nucleus queens, and 5 of the 6 Harp queens. At all observation dates, colonies with Califor- nia queens or nucleus queens had more sealed brood than those with Harp queens; the differences were significant on 30 May and 15 July (fig. 1, p < 0.05). In addition, nucleus queens produced slightly more brood than California queens, although the results were not significant at any dates (p > 0.05). J. ENTOMOL. Soc. Brit. CoLuBIA 82 (1985), DEc. 31, 1985 37 Surface areas of honey (syrup) were not significantly different at each observation date. Through July, the amount of pollen stored in all col- onies increased from an average of 808 cm? on 20 June to 2800 cm* on 5 August (Fig. 1), but there were no significant differences at any measuring date between the treatments (p > 0.05). The pattern of net colony weights (Fig. 1) was similar to that of sealed brood, with the Harp queens being lowest all season, but the differences were statistically significant only on 30 May (p < 0.05). DISCUSSION The results of this and other studies suggest that queen survival using the Harp overwintering system may be too variable for commercial use. Storage of viable mated queens for 5-6 months during the winter with low mortality would be necessary for By ‘LHOISM ANO109 LIN MOONY WAAAY 7.08 oO NOOO Fg California PA Nucleus “Id oe 6.8, w vv ~ N hia O00L x 749 ‘GOOus G31V3S BB terp spring package production, but in our studies, mor- tality from October - April ranged from 28% in 1983 to 79% in 1984. Similarly, Szabo (1977) found 77-98% mortality during 5 months of winter storage. In contrast, Harp, (1969) found only 5% mortality during the winter in Wisconsin. Levin- sohn and Lensky (1981), using a system of confining queens singly and adding sealed brood every 10-14 days, reported a 5-year average of 20% mortality after 5 months storage in queenless colonies in Israel. The highest mortalities were reported by Szabo, which may have resulted from failing to add carbohydrate during the winter. Carbohydrate was fed to colonies in the other studies, by shifting frames of honey closer to stored queens every 2-4 weeks (Harp 1969), or by supplying sugar syrup and/or icing sugar every 7-10 days except during the major nectar flow (Levinsohn and Lensky 1981) or irregularly (our studies). The relatively high queen 0001 x 742 ‘A3NOH -overwintered queens and spring-reared queens imported from California. N = i=) 0001 x 29 'N3170d Fig. 1. Productivity of Harp and nucleus 38 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 survivals found in Israel and Wisconsin may have been due to the availability of nectar and addition of brood in Israel during the storage, and to regular movement of honey closer to queens in the Wiscon- sin studies. But the importance of carbohydrate and the addition of brood in winter survival needs to be more rigorously examined before drawing conclu- sions concerning its importance in queen overwintering. The loss of queens overwintered in 2-frame nuclei was likely due to the low initial worker population and subsequent dwindling through winter. Indoor wintering was considerably more successful than outdoor. Most beekeepers use a nucleus of 3-5 frames for outdoor overwintering, and from our experiments using 2-frames it appears that the larger nucleus is necessary. By most means of evaluation, the surviving Harp queens were inferior to the nucleus and California queens. Susceptibility to supercedure and lower productivity of Harp queens, particularly in worker production as measured by sealed brood area, suggest that either the mode or duration of storage altered their physiological condition. Sup- port for this view is derived from the observation that after removing 10 Harp queens from winter storage (April 1983), six were not accepted in tem- porary storage bank, and 5 of 6 Harp queens in- troduced to colonies were superceded by August. In his study of overwintering, Szabo (1977) reported that 5 out of 12 queens surviving from a Harp storage system were superceded or lost over a 5-month season. However, this replacement was not significantly different from that seen in colonies with queens which had been overwintered either in screened compartments which prevented entry of attendant bees, or in nuclei. The lack of significant differences in net colony weight may have been due in part to the cool, wet spring and early summer which shortened nectar flows and depressed forager activity. Scale hive records (unpublished) from the Ministry of Agriculture and Food show that May and June were dearth periods in the immediate area. Seasonal and short term weight gain have both been used as in- dicators of queen productivity in the selection of breeding stock (Szabo 1982), but in the Fraser Valley, which is characterized by unpredictable and sporadic nectar flows, net colony weight was not a reliable parameter for queen productivity. Our experience with the Harp overwintering system suggests that if it is to be used, queens might be established in nuclei made up by bees from the overwintering bank after a maximum of 4 months of storage, since queen survival begins to decline rapidly at that time. However, the usual nucleus size of 3-5 frames may prove difficult to populate in late winter. An alternative would be the use of smaller nuclei which would require fewer bees. Such units would have to be adequately protected from low temperatures. Establishment of queens in small nuclei would allow the beekeeper to evaluate acceptance and egg laying capacity and pattern before using the queen for packages or individual sales. The judicious use of sugar syrup, candy or ic- ing sugar in these nuclei would enhance the survival of queens until spring nectar sources are available. The performance of nucleus queens in 1983 reaf- firms the use of this storage method, but larger nuclei are necessary for outdoor storage due to high mortality in 2 frame units. An acceptable level of outdoor overwintering may be achieved by establishing nuclei in late August or September, allowing an extension of brood rearing into fall and ensuring that some young bees would be present through winter. Nuclei made up in late summer would also be able to take advantage of late nectar and pollen sources which may reduce the feeding requirements. Recent findings of the mite Acarapis woodi in the United States will stimulate Canadian package bee and queen production. The demand for queens in the spring may be met by a combination of nucleus overwintering, spring-reared queens, and importation from areas of the United States and New Zealand declared free of pests. However, mass overwintering should be further investigated since it requires fewer resources than nuclei and as such is a desirable long-term solution. ACKNOWLEDGEMENTS This work was supported by grants from the Agriculture and Rural Development Subsidiary Agreement (ARDSA Project 271311), the Demonstration of Agricultural Technology and Economics (DATE) program, and the B.C. Honey Producers Association to the B.C. Ministry of Agriculture and Food, Apiculture Branch; and Natural Sciences and Engineering Research Council (NSERC A7774) and Science Council of British Col- umbia grants to M.L.W. We also wish to thank Mr. George Grant and Mrs. Joan Smirle for allowing us to maintain apiaries on their properties. REFERENCES Canadian Honey Council. 1982. Minutes and Proceedings. Corner, J. 1977. Provincial Apiarist’s Report. Harp, E. R. 1969. A method of holding large numbers of honey-bee queens in laying condition. Am. Bee J. 109:340-341. Levinsohn, M. and Y. Lensky. 1981. Long-term storage of queen honeybees in reservoir colonies. J. apic. Res. 20:226-233. McCutcheon, D. M. 1984. Final report: B.C. honeybee stock improvement project. Pankiw, P. and J. Corner. 1970. Production of package bees in southern British Columbia, Canada. J. apic. Res. 9:29-32. J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 39 Szabo, T. I. 1977. Overwintering of honeybee queens. 2. Maintenance of caged queens in queenless col- onies. J. apic. Res. 16:41-46. . 1982. Phenotypic correlations between colony traits in the honey bee. Am. Bee J. 122:711-716. Winston, M. L. 1983. Trends in Canadian beekeeping. Am. Bee J. 123:837-840. APHIDS TRAPPED IN OKANAGAN CHERRY ORCHARDS AND THE FAILURE OF NINE SPECIES TO TRANSMIT LITTLE CHERRY DISEASE A. R. FORBES!, C. K. CHAN!, J. RAINE! AND R. D. McMULLEN? 1Agriculture Canada Research Station, Vancouver, B.C. V6T 1X2 *Agriculture Canada Research Station, Summerland, B.C. VOH 1Z0 ABSTRACT In a search for possible vectors of little cherry disease (LCD) more than 118 aphid species, including 13 new records for B.C., were trapped in yellow-pan water traps set out in Okanagan cherry orchards. Eleven species were trapped more than 250 times. In descending order of occurrence, they were Aphis pomi de Geer, Aphis nasturtii Kaltenbach, Myzus persicae (Sulzer), Pemphigus populivenae Fitch, Aphis citricola van der Goot, Hyperomyzus lactucae (Linnaeus), Capitophorus horni Borner, Metopolophium dirhodum (Walker), Rhopalosiphum padi (Linnaeus), Capitophorus hippophaes (Walker) and Hayhurstia atriplicis (Linnaeus). Nine species of aphids reproducing on Prunus spp. including Aphis pomi, Asiphonaphis_ pruni Brachycaudus _helichrysi Wilson & Davis, (Kaltenbach), Brachycaudus_ cardui Dysaphis_ plantaginea (Linnaeus), (Passerini), Hyalopterus pruni (Geoffroy), Myzus cerasi (Fabricius), Myzus persicae, and Rhopalosiphum cerasifoliae (Fitch) failed to transmit LCD to test trees of c.v. Sam. INTRODUCTION As part of a search for the possible vectors of little cherry disease (LCD), we made a survey of the aphids occurring in Okanagan cherry orchards from June to October in 1975 and 1976. This paper reports more than 118 species collected during the survey, including 13 new records for B.C. We also include a record of attempts to transmit LCD with 9 species of aphids from Prunus spp. METHODS Survey Traps similar to those used by Moericke (1951) and Taylor (1960) were used in the survey. They consisted of 29 x 13 cm bright yellow, round plastic pans each with a screened 2.5 cm hole about 2.5 cm below the rim to prevent overflow and loss of specimens in the event of rain. Each pan was filled with about 8 cm of water and a few drops of liquid detergent were added to reduce surface tension and to cause any aphids alighting on the surface of the water to sink. The pans were set on adjustable stands and were maintained at the same height as the orchard undercover. Aphids were removed from the pans at weekly or semiweekly intervals and preserved in 70% alcohol for later identification. When the pans were cleaned, fresh water and detergent were added. Identifications were made by A. R. Forbes and C. K. Chan. Some specimens were submitted to W. R. Richards, Biosystematics Research Institute, Ottawa, Ontario, for confirma- tion of identifications. Six traps were placed in each of 3 cherry orchards in 1975 and 6 were placed in each of 11 cherry or- chards in 1976. Half of the traps were placed within the orchards and half were placed on the periphery. The orchards were located in the Penticton, Naramata and Summerland areas where LCD was still spreading. One orchard was located about 1.5 km east of the centre of Penticton, where the disease was first detected; 5 were located 2.5 to 10 km north of Penticton toward Naramata and 5 more were located in the Summerland area, 2 at the Research Station and 3 located 1.5 to 5 km north of the Station. The orchards in which the traps were located were of mixed sweet cherry varieties, including Bing, Lambert, Van and Sam. The ground cover varied from dense to sparse and consisted mainly of mowed grasses and broadleafed weeds; a few or- chards were clean cultivated or with sparse weed growth. Flora adjacent to the orchards consisted of grasses or other fruit trees including apples, pears, plums, peaches and apricots or sometimes, shrubs such as chokecherry, saskatoon, snowberry, rabbit- bush, sagebrush, Oregon grape and sumac. Occa- sionally, Douglas fir, ponderosa pine, maple and poplar were also nearby. Transmission tests More than 700 transmission tests were conducted with 9 species of aphids reproducing on cherry and other Prunus species. For each test 50 or more aphids were confined in small cylindrical leafcages, first on LCD source trees for 2 or 3 days then on Sam indicator trees for 4 or 5 days. The indicator trees were then sprayed to kill the 40 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), Dec. 31, 1985 aphids and observed for red-leaf symptoms characteristic of LCD (Welsh and Cheney 1976). The species of aphids used and the number of tests conducted (in brackets) were as follows: Aphis pomi de Geer (4): Asiphonaphis pruni Wilson & Davis (81); Brachycaudus cardui (Lin- naeus) (19); Brachycaudus helichrysi (Kaltenbach) (99); Dysaphis plantaginea (Passerini) (35); Hyalopterus pruni (Geoffroy) (21); Myzus cerasi (Fabricius) (176); Myzus persicae (Sulzer) (138); and Rhopalosiphum cerasifoliae (Fitch) (130). RESULTS AND DISCUSSION Survey Table 1 summarizes the total numbers of alate aphids trapped in the survey of Okanagan cherry orchards in 1975 and 1976. The traps caught 43,758 aphids during the 2 year period. More than 40 per- cent of them were trapped in August. Most of the species trapped were migrants from diverse hosts other than cherry (Forbes and Chan 1978b). Only Hyalopterus pruni, Myzus cerasi, Nearctaphis bakeri (Cowen), and Rhopalosiphum nymphaeae (Linnaeus) are known to reproduce on sweet cherry, Prunus avium, in British Columbia (Forbes and Chan 1978b). Eleven species were trapped more than 250 times. In descending order of occurrence, they were Aphis pomi, Aphis nasturtii Kaltenbach, Myzus persicae, Pemphigus populivenae Fitch, Aphis citricola van der Goot, Hyperomyzus lactucae (Lin- naeus), Capitophorus horni Borner, Metopolophium dirhodum (Walker), Rhopalosiphum padi (Linnaeus), Capitophorus hippophaes (Walker) and Hayhurstia atriplicis (Linnaeus). Thirteen of the species trapped were new records for B.C. (Forbes and Chan 1978a, 1980, 1981, 1983). They were: Aphis craccae Linnaeus; Brachycolus asparagi Mordvilko; Chaitophorus nigricentrus Richards; Chaitophorus pusillus Hottes & Frison; Chaitophorus saliciniger (Knowlton); Colopha ulmicola (Fitch); Cryptaphis bromi Robinson; Forda formicaria von Heyden; Kakimia polemonii (Gillette & Palmer); Macrosiphoniella ludovicianae (Oestlund); Rhopalomyzus lonicerae (Siebold); Therioaphis trifolii (Monell); and Uroleucon hieracicola (Hille Ris Lambers). Transmission tests Aphid species that are known to colonize cherry or related Prunus spp. (Forbes and Chan 1978b) were considered to be the best vector candidates and were chosen for testing. Transmission tests with Aphis pomi, Asiphonaphis pruni, Brachycaudus cardui, Brachycaudus helichrysi, Hyalopterus pruni, Myzus cerasi, Myzus persicae and Rhopalosiphum cerasifoliae failed to transmit LCD. Thus 8 of the 13 species of aphids known from Prunus spp. in British Columbia (Forbes and Chan 1978b) were tested. TABLE 1. Total number of alate aphids trapped in Okanagan cherry orchards 1975 and 1976. Species June Acyrthosiphon lactucae (Passerini) 12 Acyrthosiphon macrosiphum (Wilson) 8 Acyrthosiphon pisum (Harris) 23 Acyrthosiphon spp. 8 Amphorophora agathonica Hottes 9 Amphorophora parviflori Hill - Amphorophora spp. 23 Anoecia corni (Fabricius) - Aphis citricola van der Goot = Aphis craccae Linnaeus 1 Aphis fabae Scopoli 8 Aphis helianthi Monel] - Aphis nasturtii Kaltenbach 27 Aphis pomi de Geer Aphis spp. Appendiseta robiniae (Gillette) 19 Asiphonaphis pruni Wilson & Davis 1 July August Sept. Oct. Total 9 : . : 21 4 1 1 - 14 58 1 3 - 85 53 79 17 12 169 8 - - - 17 1 - - - 1 7 8 17 18 73 9 15 34 3 61 - 1789 - - 1789 - 6 - - 7 i 3 58 20 100 1 - 34 - 35 2445 5593 - - 8065 3551 9470 437 3 13659 121 24 67 60 392 108 6 - - 133 - - - - 1 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 TABLE lL. (continued) Species Asiphum sp. Aulacorthum solani (Kaltenbach) Aulacorthum spp. Boernerina occidentalis H.R.L. & Hottes Brachycaudus cardui (Linnaeus) Brachycaudus helichrysi (Kaltenbach) Brachycaudus sp. Brachycolus asparagi Mordvilko Brevicoryne brassicae (Linnaeus) Cachryphora sp. Calaphis spp. Capitophorus elaeagni (del Guercio) Capitophorus hippophaes (Walker) Capitophorus horni Borner Cavariella aegopodii (Scopoli) Cavariella pastinacae (Linnaeus) Cavariella spp. Ceruraphis viburnicola (Gillette) Chaetosiphon fragaefolii (Cockerel1) Chaitophorus nigrae Oestlund Chaitophorus nigricentrus Richards Chaitophorus populicola Thomas Chaitophorus populifolii (Essig) Chaitophorus pusillus Hottes & Frison Chaitophorus saliciniger (Knowlton) Chaitophorus spp. Chaitophorus viminalis Monel] Colopha ulmicola (Fitch) Cryptaphis bromi Robinson Cryptaphis sp. Cryptomyzus galeopsidis (Kaltenbach) Cryptomyzus ribis (Linnaeus) Cryptomyzus spp. Diuraphis frequens (Walker) Dysaphis plantaginea (Passerini) Dysaphis sp. Eriosoma lanigerum (Hausmann) June 36 35 July 13 10 August o7 29 Sept. 23 95 Oct. Total 146 50 59 4] 42 J. ENTOMOL. Soc. BriT. COLUMBIA 82 (1985), DEc. 31, 1985 TABLE lL. (continued) Eriosoma spp. 5 1 - 5 5 16 Essigella sp. - - - 1 - 1 Euceraphis gillettei Davidson 2 2 3 - - 7 Euceraphis sp. 1 - - - - 1 Fimbriaphis spp. 1 3 5 288 - 297 Forda formicaria von Heyden 2 - = = - 2 Forda sp. 2 - - = - 2 Hayhurstia atriplicis (Linnaeus) 6 54 209 10 1 280 Hyadaphis sp. 1 2 - - - 3 Hyalopterus pruni (Geoffroy) 1 - 2 1 - 4 Hyperomyzus lactucae (Linnaeus) 23 83 119 328 114 667 Illinoia davidsoni (Mason) - - 1 - - i} Illinoia spp. 18 3 13 19 | 60 Kakimia polemonii (Gillette & Palmer) 3 - - - - 3 Kakimia wahinkae (Hottes) - 1 - - - 1 Lipaphis erysimi (Kaltenbach) 1 2 - - ~ 3 Macrosiphoniella ludovicianae (Oestlund) 2 - - - - 2 Macrosiphoniella sp. - 1 - - - 1 Macrosiphum euphorbiae (Thomas) 8 4 2 - - 14 Macrosiphum rosae (Linnaeus) 5 3 - 4 2 14 Macrosiphum spp. 52 33 18 14 5 122 Metopolophium dirhodum (Walker) 1 2 5 213 182 403 Myzaphis sp. 1 - - - - d! Myzocallis coryli (Goeze) 5 3 - - - 8 Myzocallis spp. Zz 37 5 i - 45 Myzodium modestum (Hottes) 1 1 - - - 2 Myzus ascalonicus Doncaster - - - 5 - 5 Myzus cerasi (Fabricius) 42 98 1 3 1 145 Myzus persicae (Sulzer) 4706 2717 164 161 108 7856 Myzus spp. - - 1 1 2 4 Nasonovia spp. 2 2 1 - - 5 Nearctaphis bakeri (Cowen) 1 1 - 4 - 6 Nearctaphis sensoriata (Gillette & Bragg) 1 - 1 5 ~ 7 Nearctaphis spp. 3 i - - - 4 Oestlundiella flava (Davidson) 3 3 6 = - 12 Pemphigus bursarius (Linnaeus) - 1 - - - 1 Pemphigus populivenae Fitch 3802 787 5 3 - 4597 Pemphigus spp. 389 85 8 8 18 508 Periphyllus brevispinosus Gillette & Palmer 1 ik - - - 2 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEc. 31, 1985 43 TABLE 1. (continued) Periphyllus testudinaceus (Fernie) - - 1 - - i} Phorodon humuli (Schrank) 63 42 7 - - lid Phyllaphis fagi (Linnaeus) 1 - - - - 1 Prociphilus spp. - 2 - 44 8 54 Pterocomma bicolor (Oestlund) if - - - - 1 Rhopalomyzus lonicerae (Siebold) - - - 1 - il Rhopalomyzus poae (Gillette) - - - 5 8 13 Rhopalomyzus spp. 2 - - 22 5 29 Rhopalosiphoninus staphyleae (Koch) - i! - - - 1 Rhopalosiphum insertum (Walker) - - - - 146 146 Rhopalosiphum padi (Linnaeus) - - 1 177 149 327 Rhopalosiphum spp. - - - 1639 116 1755 Sipha elegans del Guercio 1 - - 1 - 2 Sitobion avenae (Fabricius) 4 40 9 18 - 71 Sitobion manitobense (Robinson) 1 - - - ~ 1 Therioaphis trifolii (Monel1) - 2 1 - - 3 Tinocallis platani (Kaltenbach) 3 13 15 - - 31 Tuberculatus annulatus (Hartig) - 1 - - - 1 Uroleucon cirsii (Linnaeus) - 1 - - - 1 Uroleucon hieracicola (Hille Ris Lambers) - 3 - - - 3 Uroleucon spp. 7 29 13 53 8 110 Uroleucon taraxaci (Kaltenbach) 4 10 - 6 1 21 Utamphorophora humboldti (Essig) 3 1 - - - 4 Utamphorophora spp. - - 1 ] 1 3 Wahlgreniella nervata (Gillette) 3 1 9 4 - ial Total 10,027 10,907 17,880 3,891 1,053 43,758 % of total 22.9 24.9 40.9 8.2 2.4 Dysaphis plantaginea from apple was also tested. ACKNOWLEDGEMENTS It too failed to transmit LCD. The authors wish to acknowledge the help of C. More recently it was shown by R. D. McMullen, Chong and W. Hurdal who made trap collections that the apple mealybug, Phenacoccus aceris and assisted in the aphid transfers at Summerland. (Signoret) is a vector of LCD (Agr. Can. 1982). It is unlikely, therefore, that any aphid species can transmit the disease. REFERENCES Agriculture Canada. 1982. Transmission of little cherry disease by apple mealybug. Research Branch Report 1981. p. 382. Forbes, A. R. and C. K. Chan. 1978a. The aphids (Homoptera: Aphididae) of British Columbia. 6. Further additions. J. ent. Soc. Brit. Columbia: 75:47-52. Forbes, A. R. and C. K. Chan. 1978b. The aphids (Homoptera: Aphididae) of British Columbia. 7. A revis- ed host plant catalogue. J. ent. Soc. Brit. Columbia 75:53-67. 44 J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), Dec. 31, 1985 Forbes, A. R. and C. K. Chan. 1980. The aphids (Homoptera: Aphididae) of British Columbia. 8. Further additions. J. ent. Soc. Brit. Columbia 77:38-42. Forbes, A. R. and C. K. Chan. 1981. The aphids (Homoptera: Aphididae) of British Columbia. 9. Further additions. J. ent. Soc. Brit. Columbia 78:53-54. Forbes, A. R. and C. K. Chan. 1983. The aphids (Homoptera: Aphididae) of British Columbia. 11. Further additions. J. ent. Soc. Brit. Columbia 80:51-53. Moericke, V. 1951. Eine Farbfalle zur Kontrolle des Fluges von Blattlausen insbesondere der Pfirsichblat- tlaus, Myzodes persicae (Sulz.). Nachrichtenbl. Dtsch. Pflanzenschutzdienst. (Berl.) 3:23-24. Taylor, L. R. 1960. The distribution of insects at low levels in the air. J. Animal. Ecol. 29:45-63. Welsh, M. F. and P. W. Cheney. 1976. Virus diseases of sweet cherry. Little Cherry. U.S. Dept. Agr. Handbook 437:231-237. SEASONAL ACTIVITY OF ICHNEUMONID PUPAL PARASITOIDS OF OPEROPHTERA SPP. (LEPIDOPTERA:GEOMETRIDAE) L. M. HUMBLE Graduate Student Department of Biology University of Victoria Victoria, B.C., V8W 2Y2 ABSTRACT Field placement of cocoons of Operophtera spp. was used to determine the timing of attack by pupal parasitoids of the winter moth, Operophtera brumata (L.), and the Bruce spanworm, O. bruceata (Hulst). Coccygomimus hesperus Tow... & Tow., the most abundant parasitoid recovered, attacked Operophtera pupae from early June until the end of August. At least two generations of C. hesperus oc- cur each season. Buathra dorsicarinata (Pratt) was not recovered in numbers large enough to determine its timing of attack and no pupae parasitized by Cratichneumon sp. were recovered. INTRODUCTION Three native species of Ichneumonidae, Coc- cygomimus hesperus Tow. & Tow., Buathra dor- sicarinata (Pratt) and an undescribed species of Cratichneumon are known to attack pupae of the introduced winter moth, Operophtera brumata (L.), and the native Bruce spanworm, O. bruceata (Hulst), on southern Vancouver Island (Humble in press). Over their range both C. hesperus and B. dorsicarinata have long flight seasons; the former is active from mid-May to late Dec., and the latter from mid-May to late Aug. (Townes and Townes 1960, 1962). In the Victoria area, the flight season for both species begins in mid-May. Buathra dor- sicarinata flies until early Aug. (Humble in press), and C. hesperus until late Aug. (Humble unpub. data). The range and flight season of Cratichneumon sp. are unknown. The timing of attack by these parasitoids on Operophtera pupae is unknown. Both winter moth and Bruce spanworm larvae mature between late May and early June, drop to the ground and pupate in silken cocoons. Pupae are present from mid-June to mid-Nov., and adults begin to emerge in early Nov. Although Operophtera pupae are present, they may not be suitable as hosts throughout the flight seasons of the parasitoids, since increasing host age can reduce the suitability of a host for parasitoid development (Schultz and Kok 1979). This study was carried out to determine the timing of attack by the pupal parasitoids on Operophtera pupae. MATERIALS AND METHODS Operophtera pupae were obtained by beating mature larvae from willow, broad-leaf maple and Garry oak on the University of Victoria campus. The larvae were provided with a substrate of moistened sand:vermiculite:peat moss (2:1:1) in screen-covered 25.4 cm plastic plant pots for pupa- tion. The pots were held indoors at 15°C and 70% RH. The substrate was periodically sprayed with a 1% solution of sodium proprionate to inhibit the growth of mould (Maybee and Wylie 1961). Co- coons were sieved from the substrate as needed for field placement. Pupae were placed in the field in four-mesh wire cages similar to those used by Price (1970) to pre- vent predation by small mammals or birds. Five cages were placed along the margins of a small (0.12 ha) stand of heavily defoliated willows growing in association with arbutus, Douglas fir, broad-leaf maple and red-osier dogwood. A thick shrub layer of snowberry, salmonberry, thimbleberry, Pacific blackberry, ocean spray and Rosa spp. was present along the margins of the stand. J. ENTOMOL. Soc. BRIT. COLUMBIA 82 (1985), DEC. 31, 1985 45 Five cocoons were placed on the surface of the ground in each of the cages at the beginning of each weekly sample interval from 10 June to 17 Sept., and each two-week interval from 17 Sept. to 15 Oct., 1982. No cocoons were placed in the cages from 2-10 Sept. At the end of each sample interval the cocoons in each of the cages were replaced with fresh cocoons and individually reared at 20°C and 70% RH. The emergence date was recorded for each adult parasitoid. Developmental time from egg to adult parasitoid at 20°C was estimated by setting the midpoint of field exposure as the date of parasitism. Emerged parasitoids were identified with the keys provided in Townes and Townes (1960), and compared with reference specimens. All non- emerged pupae were dissected for evidence of parasitism in June 1983. Exuviae of final-instar lar- vae of hymenopterous parasitoids were mounted on microscope slides for identification following the procedure of Finlayson (1960) and identified using keys provided by Gillespie and Finlayson (1981) and Humble (in press). Some cocoons used for field placement were found to contain dead Operophtera larvae or larval- pupal parasitoids (puparia of Cyzenis (Diptera:Tachinidae) or final-instar larvae of Triclistus or Agrypon (Hymenoptera: Ichneumonidae)). None of the pupal parasitoids recovered are known hyperparasites (Carlson 1979; Humble in press; Townes and Townes 1960, 1962), therefore, the number of cocoons present during each sample interval was corrected to exclude those cocoons containing larval/pupal parasitoids. The G- test for goodness of fit (Sokal and Rohlf 1981) was applied to determine if the proportion of pupae parasitized by C. hesperus differed significantly between sample intervals. 0.4 23 9° A) PROPORTION 5° 22 29 «5 JULY 10 17 24 1 8 JUNE RESULTS A total of 375 Operophtera cocoons were placed in the field and all but five of the cocoons were recovered. The losses were probably due to preda- tion by Carabidae. Twenty-three of the non- emerged cocoons contained the remains of dead host larvae or larval-pupal parasitoids. Thirty-four of the pupae were parasitized by C. hesperus and two were parasitized by B. dor- sicarinata. No pupae parasitized by Cratichneumon sp. were recovered. The proportion of cocoons parasitized per sample interval by the two species is shown in Fig. 1. Coccygomimus hesperus attacked Operophtera pupae from early June through to the end of Aug., while B. dorsicarinata was recovered only during the 12-19 Aug. sample interval. 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