Anderbrant, O., & Schlyter, F. 1987. Differences in morphology and sexual size dimorphism between the dutch elm disease vectors scolytus-laevis and scolytus-scolytus coleoptera scolytidae. J. Appl. Entomol. 103 (4). 378-386. ab The external differences between the well-documented S. scolytus and the little studied S. laevis are clarified with the help of SEM micrographs of the frons and abdomen of both sexes of the two species. The convex frons of both male and female S. scolytus is densely covered with short hairs. S. laevis males have a flat frons with long hairs in a pair of bundles, whereas the females have a convex and nearly bald frons. Males of S. scolytus are readily distinguished from females by their long yellow tufts of hair on the anal segment. The pronotal width and elytron length are significantly larger for S. scolytus females than for males. In S. laevis males and females are of the same size but significantly smaller than S. scolytus. The difference between the species in intersexual size variation and frontal hair cover suggests differences in their mating systems. LG EN.

Anderbrant, O., & Schlyter, F. 1987. Ecology of the dutch elm disease vectors scolytus-laevis and scolytus-scolytus coleoptera scolytidae in southern sweden. J. Appl. Ecol. 24 (2). 539-550. ab The distribution and phenology of the elm bark beetles Scolytus laevis and S. scolytus were studied at an infestation centre in Scania, southernmost Sweden in 1983-85. Two rings of pheromone-baited sticky traps surrounded the elm wood 'Orups almskog', at 20-300 m and 1-2 km outside the forest edge. The distribution of both Scolytus laevis and S. scolytus was very concentrated, most beetles being caught at sites in the inner ring near the forest, while < 1% of the total were caught in the outer ring. Seventeen baited sticky traps, positioned at 5 km in a grid surrounding Orup did not catch any beetles. The results indicate a low proportion of dispersing beetles. Emergence from logs and trap catches showed a first peak in July in the 3 years studied. Flight activity was recorded from the end of May to September for both species. A second peak of activity was evident in August in two of the years for S. scolytus, indicating a second generation. The commercially available racemic 4-methyl-3-heptanol was attractive to S. scolytus over a range of release rates (0.3-20 mg day-1) but less so for S. laevis. The efficiency of the sticky trap (white cardboard) was similar to or better than that of non-sticky window traps and drainpipe traps with exterior funnels. LG EN.

Barger, J.H. 1984. Evaluation of hydraulically applied methoxychlor to protect american elms ulmus-americana from feeding by the smaller european elm bark beetle scotytus-multistriatus coleoptera scolytidae. J. Econ. Entomol. 77 (3). 794-797. ab U. americana L. were sprayed by hydraulic sprayer with various concentrations of methoxychlor, with and without stickers, in different seasons and cities to determine chemical deposit and efficacy against S. multistriatus (Marsham), a vector of the Dutch elm disease fungus (Ceratocystis ulmi). GLC assays and beetle bioassays were used to quantify methoxychlor deposits. Methoxychlor deposit was unaffected by the addition of spray sticker, but concentration, residual period, season sprayed, and skill of the spray crew significantly affected deposit. LG EN.

Barger, J.H., & Hock, W.K. 1971. Distribution of dutch elm disease and the smaller european elm bark beetle in the usa as of 1970. Plant. Dis. Rep. 55 (3). 271-272.

Barger, J.H., Cannon, W.& N., JR. 1987. Response of smaller european elm bark beetles to pruning wounds on american elm. J. Arboric. 13 (4). 102-104.

Barger, J.H., Cuthbert, R.A., & Roberto, N.H. 1971. Assessment of 3 pre cold storage preparations on the feeding response of scolytus-multistriatus and the degradation of dicrotophos. J. Econ. Entomol. 64 (3). 621-624.

Barger, J.H., Cuthbert, R.A., Cannon, W.& N., JR. 1984. Numbers of scolytus-multistriatus coleoptera scolytidae caught on multilure-baited sticky traps increase with methoxychlor. J. Econ. Entomol. 77 (5). 1251-1253. ab Multilure-baited sticky traps were attached to various methoxychlor-sprayed and unsprayed trap sites to determine the effect of the insecticide treatments on catches of the smaller European elm bark beetle, S. multistriatus (Marsham). Significantly more bark beetles were captured by baited sticky traps attached to the boles to sprayed healthy American elms, Ulmus americana L., and also by traps attached to the boles of sprayed elms infected with the Dutch elm disease fungus (Ceratocystis ulmi), than were captured by traps on comparable unsprayed elms. Bark beetle catches on traps attached to sprayed and unsprayed utility poles and tree trap sites other than elms were not significantly different. These test suggest that other beetle attractants associated with healthy and diseased elms and the presence of methoxychlor on the trap sites significantly affected trap catches. LG EN.

Basset, Y., Favaro, A., Springate, N.D., & Battisti, A. 1992. Observations on the relative effectiveness of scolytus-multistriatus marsham and scolytus-pygmaeus fabricius coleoptera scolytidae as vectors of the dutch elm disease. Mitt. Schweiz. Entomol. Ges. 65 (1-2). 61-67. ab Some aspects of the relative effectiveness of Scolytus multistriatus and S. pygmaeus as vectors of the Dutch elm disease were studied in north-eastern Italy. About 58% of beetles collected at emergence were contaminated with the pathogen Ophiostoma ulmi, with no interspecific difference being observed. Under controlled conditions (beetles saturated with spores, high R.H.), successful transmission of the pathogen during maturation feeding of beetles on elm saplings was achieved in 11% of the cases. Again, no significant interaction of the species was observed, although samples size was low. These data suggest that the specific size of beetles and concomitant subordination to specific breeding habitats is unimportant in affecting the proportion of beetles contaminated with the pathogen in humid conditions. With reference to the effective transmission of the disease in the field, the influence of these factors is less clear. If the trends reported above are verified and observed in natural conditions, it would be imperative to destroy also small elm branches during sanitation felling programes, at least when these are performed in humid areas. LG EN.

Beaver, R.A. 1969. Natality mortality and control of the elm-d bark beetle scolytus-scolytus coleoptera scolytidae. Bull. Entomol. Res. 59 (part 3). 537-540.

Benson, J.F. 1974. Elm bark beetles the vectors. Biol. J. Linn. Soc. 6 (4). 359.

Benson, J.F., & Walker, C. 1974. Abundance of odinia-meijerei diptera odiniidae. Entomol. Mon. Mag. 110 (1316-18). 50.

Blight, M.M., Fielding, N.J., King, C.J., Ottridge, A.P., Wadhams, L.J., & Wenham, M.J. 1983. Field response to the dutch elm disease ceratocystis-ulmi vectors scolytus-multistriatus and scolytus-scolytus coleoptera scolytidae to 4 methyl-3 heptanol baits containing alpha beta gamma or delta multistriatin. J. Chem. Ecol. 9 (1). 67-84. ab The field responses of English populations of the Dutch elm disease vectors, S. multistriatus and S. scolytus to baits containing 4-methyl-3-heptanol, a host synergist ((-)-.alpha.-cubebene or (-)-limonene) and (.+-.)-.alpha.-, (+)-.beta.-,(-)-.beta., (.+-.)-.gamma.-, or (.+-.) were examined. (.+-.)-.alpha.-Multistriatin, released at 5-10 .mu.g/day, enhanced the response of S. multistriatus to baits containing 4-methyl-3-heptanol and either of the host synergists but had no effect on the capture of S. scolytus. The release of larger amounts (57 or 365 .mu.g/day) of (.+-.)-.alpha.-multistriatin interrupted the response of both species to the 4-methyl-3-heptanol baits. .alpha.-Multistriatin has multiple functions as a behavior-modifying substance for the 2 beetles. The (+)-.beta.-, (-)-.beta.-, (.+-.)-.gamma.- and (.+-.) were inactive when released at 5-10 .mu.g/day. One bait can be formulated to capture both species. LG EN.

Blight, M.M., Henderson, N.C., & Wadhams, L.J. 1983. The identification of 4 methyl-3 heptanone from scolytus-scolytus and scolytus-multistriatus absolute configuration laboratory bioassay and electro physiological studies on scolytus-scolytus. Insect. Biochem. 13 (1). 27-38. ab The identification of (4S)-4-methyl-3-heptanone among the volatiles produced when male S. scolytus (a major vector of Dutch elm disease, Ceratocystis ulmi, in Europe) bore into 4 spp. of Ulmus (U. procera, U. carpinifolia var. sarniensis, U. carpinifolia var. cornubiensis, U. glabra) is described. The quantity of 4-methyl-3-heptanone found in extracts of volatiles was 12-32% of the total amount of 4-methyl-3-heptanol present. From gas chromatographic analysis and a coupled gas chromatography-single cell recording technique, evidence was obtained for the production of 4-methyl-3-heptanone by female S. multistriatus boring in 2 Ulmus spp. These are the 1st reports of 4-methyl-3-heptanone from the order Coleoptera. Electrophysiological studies (electroantennogram and single cell recordings) and a laboratory walking bioassay indicated that (.+-.)-4-methyl-3-heptanone is biologically active towards S. scolytus. Of the olfactory cells recorded from the antennae of males and females, 11% responded preferentially to (.+-.)-4-methyl-3-heptanone at low stimulus concentrations. In the bioassay, addition of specific concentrations of this substance to a mixture of 4-methyl-3-heptanol and (-)-.alpha.-cubebene modified the type of response given by both sexes, but a significant increase in the overall response was shown only by female beetles. LG EN.

Blight, M.M., Henderson, N.C., Wadhams, L.J., Fielding, N.J., & King, C.J. 1982. Field response of elm bark beetles to baits containing 4 methyl-3 heptanone. Naturwissenschaften 69 (11). 554-555.

Blight, M.M., King, C.J., Wadhams, L.J., & Wenham, M.J. 1978. Attraction of scolytus-scolytus to the components of multilure the aggregation pheromone of scolytus-multistriatus coleoptera scolytidae. Experientia. Basel. 34 (9). 1119-1120.

Blight, M.M., Mellon, F.A., Wadhams, L.J., & Wenham, M.J. 1977. Volatiles associated with scolytus-scolytus beetles on english elm. Experientia. Basel. 33 (7). 845-847.

Boutz, G.E., Brewer, J.W., & Bishop, J.N. 1985. Capture patterns of scolytus-multistriatus coleoptera scolytidae attracted to a pheromone-baited trap. Z. Angew. Entomol. 99 (4). 366-370. ab How accurately the elm bark beetle, S. multistriatus (Marsham) is able to locate a pheromone lure was determined. A large trap having 4 surfaces coated with a sticky insect-trapping material, had each surface in turn baited with multilure. While multilure is an effective beetle attractant, the beetles do not locate the pheromone source with sufficient discrimination to consistently make contact with a workable size trapping surface. The practice of placing baited traps in stands of elm trees may thus increase the level of Dutch elm disease by attracting beetles to the area without capturing them on the traps presently employed. LG EN.

Brasier, C.M. 1996. Low genetic diversity of the Ophiostoma novo-ulmi population in North America. Mycologia 88 (6). 951-964. Issn 0027-5514. ab A sample of 112 Ophiostoma novo-ulmi isolates across the range of Dutch elm disease in North America from California to Nova Scotia revealed only 16 different vegetative compatibility (vc) types. One vc type, the North American vc supergroup (AMSG) was predominant at 58% of the sample. Another vc type, the American second vc supergroup (AM2SG), which was genetically related to the AMSG, represented 20% of the sample. A third vc type, the European vc supergroup (EUSG), represented 10%. The remaining 13 isolates constituted a small but highly heterogeneous component of 13 unique vc types. No differences were detected in the mean growth rates or pathogenicities of the AMSG, AM2SG, EUSG or heterogeneous component. Only 2 of the 112 isolates were found to be infected with deleterious cytoplasmically transmissible mycoviruses ('d-factors'). This low level of genetic diversity among North American O. novo-ulmi isolates contrasts markedly with the very high diversity in current European populations. The combination of low d-infection frequency, low vc type diversity and the presence of a less efficient Dutch elm disease vector (Scolytus multistriatus) in North America also suggests that North American a novo-ulmi populations might be potential targets for attempted biological control of Dutch elm disease via the release of d-factors. Two recent O. novo-ulmi outbreak areas, the Willamette Valley, Oregon and Washington DC, were shown to exhibit a clonal (single vc type, single sexual compatibility type) population free from d-factors. They might therefore be favorable locations for an experimental d-factor release. LG EN.

Brasier, C.M., & Mehrotra, M.D. 1995. Ophiostoma himal-ulmi sp. nov., a new species of Dutch elm disease fungus endemic to the Himalayas. Mycological. Research. 99 (2). 205-215. Issn 0953-7562. ab In September-October 1993 a research survey was conducted in northern Himachal Pradesh, western Himalayas, as part of an investigation into the origins of Dutch elm disease. No disease symptoms were observed in the area, but an apparently endemic Ophiostoma similar to the known Dutch elm disease pathogens Ophiostoma ulmi and O. novo-ulmi was isolated from around breeding galleries of scolytid beetles in the bark of Ulmus wallichiana. Over 200 isolations of the fungus were made. These were later resolved into a minimum of 20 different genotypes, which were used to further characterize the fungus. Like O. ulmi and O. novo-ulmi the Himalayan Ophiostoma is outcrossing and heterothallic, with two sexual compatibility types, A and B, occurring in a near 1:1 ratio in nature. In interfertility tests, strong pre- and post-zygotic reproductive isolation was revealed between the Himalayan Ophiostoma and sexually compatible isolates of O. ulmi or the EAN or NAN races of O. novo-ulmi. The Himalayan Ophiostoma also exhibits a unique combination of physiological and morphological characteristics including a distinctive colony type, ability to produce synnemata on malt extract agar, production of perithecia with long necks, a very high level of cerato-ulmin toxin production in liquid shake cultures, and moderate to strong vascular wilt pathogenicity on U. procera. Its reproductive isolation from O. ulmi and O. novo-ulmi and its other biological features demonstrate that it is a distinct sibling species from O. ulmi and O. novo-ulmi, and it is designated as a new species, Ophiostoma himal-ulmi sp. nov. The discovery of O. himal-ulmi should help resolve the problem of the origins of Dutch elm disease, while the occurrence of an apparently endemic Dutch elm disease system in the Himalayas may present new opportunities for the biological control of the disease elsewhere. These possibilities are discussed. LG EN.

Burdekin, D.A., Gibbs, J.N., & Mitchell, A.F. 1972. The control of dutch elm disease. G. B. For. Comm. Leafl. 54. 3-7.

Burges, H.D., Grove, J.F., & Pople, M. 1979. The internal microbial flora of the elm bark beetle scolytus-scolytus at all stages of its development. J. Invertebr. Pathol. 34 (1). 21-25. ab Adult S. scolytus, the main Dutch elm disease vector, emerged from the pupal stage with sterile guts although microorganisms were present within the pupal body. Gut sterility was maintained in a large proportion of newly formed adults while they were boring out of an elm log. The adult gut microbiol flora is mainly acquired during subsequent feeding. Differences are found between the microbial gut flora of larvae and adult S. scolytus, and of both male and female beetles. LG EN.

Cannon, W.N., Jr, Barger, J.H., & Groth, L.L. 1985. Seasonal detection of visible dutch elm disease symptoms. J. Arboric. 11 (8). 233-235. ab Most of the lightly diseased American elms (10% or less crown wilt) that were suitable candidates for fungicide injection and/or pruning therapy for Dutch elm disease were discovered in surveys during June and early July. More treatable elms were found in areas where diseased elms were removed promptly (up to 20 work days after discovery) than where removal was delayed until fall and winter, and in areas where the smaller European elm bark beetle is the primary vector of Dutch elm disease rather than where the native elm bark beetle is the primary vector. LG EN.

Carter, J.C., & Carter, L.R. 1974. An urban epiphytotic of phloem necrosis and dutch elm disease 1944-1972. Ill. Nat. Hist. Surv. Bull. 31 (4). 113-143.

Claflin, L.E., & Dooling, O.J. 1973. Dutch elm disease in montana. Plant. Dis. Rep. 57 (8). 701.

Crowson, R.A. 1981. Possible function of beetles other than scolytidae as vectors of dutch elm disease ceratocystis-ulmi in scotland uk. Glasg. Nat. 20 (2). 155-160.

Cuthbert, R.A., Peacock, J.W., Cannon, W.& N., JR. 1977. An estimate of the effectiveness of pheromone baited traps for the suppression of scolytus-multistriatus coleoptera scolytidae. J. Chem. Ecol. 3 (5). 527-538. ab An attempt was made to suppress a population of S. multistriatus (Marsham), the principal vector of Dutch elm (Ulmus spp.), disease by trapping flying beetles on sticky traps baited with synthetic pheromone. The estimated catch on 421 traps distributed throughout a 1 km2 plot in Detroit, Michigan (USA), was nearly 1 million beetles. Because an estimated 5 million beetles emerged in the plot during the study period, this preliminary trapping study had no appreciable effect on suppressing the population. Studies that employ improved materials and techniques are continuing. LG EN.

Daviault, L. 1974. Notes on the development of forest entomology in quebec canada. Ann. Soc. Entomol. Que. 19 (1/2). 45-61.

Davis, D.D., Mason, G.N., & Preacher, P.H. 1970. Dutch elm disease detected in texas. Plant. Dis. Rep. 54 (11). 931.

Doberski, J.W., & Tribe, H.T. 1978. Catenaria-auxiliaris chytridiomycetes blastocladiales identified in a larva of scolytus-scolytus coleoptera scolytidae. J. Invertebr. Pathol. 32 (3). 392-393.

Doberski, J.W., & Tribe, H.T. 1980. Isolation of entomogenous fungi from elm bark and soil with reference to ecology of beauveria-bassiana and metarhizium-anisopliae. Trans. Br. Mycol. Soc. 74 (part 1). 95-100. ab Using a selective medium, the entomogenous fungus B. bassiana was isolated in quantity from bark of elm trees and from soil at the base of trees at Culford, Suffolk and near Cambridge (UK) during 1976 and 1977. Most of the trees had died of Dutch elm disease but some were healthy. B. bassiana was present as conidia which originated from infected insects on or under the bark. By contrast Metarhizium anisopliae was isolated only once from a soil sample. Differences in the distribution of these 2 unspecialized entomogenous hyphomycetes are discussed. (Observations were made during a study concerned with the potential of entomogenous fungi for reducing population levels of the large elm bark beetle, Scolytus scolytus F., the main vector of Dutch elm disease in Britain.). LG EN.

Elliott, E.W., Lanier, G.N., & Simeone, J.B. 1975. Termination of aggregation by the european elm bark beetle scolytus-multistriatus. J. Chem. Ecol. 1 (3). 283-289. ab The attractiveness of European elm bark beetle (Scolytus multistriatus Marsham, a vector of Dutch elm disease (Ceratocystis ulmi (Buisman))) virgin females boring in elm logs (Ulmus americana L.) declined within 2 days after the introduction of males, However, in the laboratory and in the field the number of beetles attracted to female-infested bolts was not depressed by the presence of separate logs infested with males or both sexes. The decline in attractiveness following cohabitation of the sexes results from termination of the production of attractant pheromone by mated females rather than the production of anti-attractants by either sex.

Elliott, W.J., Hromnak, G., Fried, J., & Lanier, G.N. 1979. Synthesis of multistriatin enantiomers and their action of scolytus-multistriatus coleoptera scolytidae. J. Chem. Ecol. 5 (2). 279-288. ab A pheromone mixture containing enantiomerically pure (-)-.alpha.-multistriatin of known absolute configuration prepared by total synthesis was as attractive as the natural pheromone to the smaller European elm bark beetle, S. multistriatus, a vector of Dutch elm disease. Its (+)-enantiomer was no more active than controls in laboratory and field tests, and at high levels it apparently inhibited the response to the (-)-enantiomer. LG EN.

Finney, J.R., & Mordue, W. 1976. The susceptibility of the elm bark beetle scolytus-scolytus to the dd 136 strain on neoaplectana-sp. Ann. Appl. Biol. 83 (2). 311-312. ab Adults and larvae of Scolytus scolytus (a vector of Dutch elm disease fungus, Ceratocystis ulmi) were highly susceptible to the DD-136 strain of Neoaplectana sp. in the laboratory.

Finney, J.R., & Walker, C. 1977. The dd-136 strain of neoaplectana-sp as a potential biological control agent for the european elm bark beetle scolytus-scolytus. J. Invertebr. Pathol. 29 (1). 7-9. ab When logs infected with Scolytus scolytus (a transmitter of Dutch elm disease fungus, Ceratocystis ulmi) were sprayed with the DD-136 strain of Neoaplectana sp. in solutions of either distilled water, glycerin or P.B.I. wetting agent, the nematodes were efficiently dispersed and entered the logs through the insect entrance holes in the bark. Logs treated with Neoaplectana sp. contained a significantly higher proportion of dead, nematode-infected insects. No difference was found between the various methods of nematode application. Neoaplectana sp. may have a possible role in the control of S. scolytus in elm logs.

Galford, J.R., & Schreiber, L.R. 1972. Effect of feeding on twigs from benomyl treated seedlings on the smaller european elm bark beetle. J. Econ. Entomol. 65 (6). 1542.

Gibbs, J.N. 1978. Inter continental epidemiology of dutch elm disease. Grogan, Raymond G., George A. Zentmyer And Ellis B. Cowling (ed.). Annual Review Of Phytopathology, Vol. 16. X+528p. Illus. Annual Reviews, Inc.: Palo Alto, Calif., Usa. Isbn 0-8243-1316-x. 287-307.

Gibbs, J.N. Dutch elm disease ceratocystis-ulmi. G. B. For. Comm. Leafl. 19. 1971 1-11.

Gibbs, J.N., & Howell, R.S. 1972. Dutch elm disease survey 1971. G. B. For. Comm. -for. Rec. 82. 3-34.

Girling, M.A., & Greig, J. 1985. A first fossil record of scolytus-scolytus elm bark beetle its occurrence in elm decline deposits from london england uk and the implications for neolithic elm disease. J. Archaeol. Sci. 12 (5). 347-352. ab A problem which has arisen in discussions of an elm-disease explanation for the Neolithic elm decline has been the lack of fossil records of Scolytus scolytus (F.) (elm bark beetle), which is the main carrier of the fungus which causes the present epidemic of Dutch Elm Disease. Now, the discovery of wing cases of two individuals from elm decline deposits at Hampstead Health, London, proves that the beetle was present in Britain during this episode. The deposits in which it occurs are described, and the various implications for elm disease causing, aiding or at least occurring during this stage of the early Neolithic are discussed. LG EN.

Grootaert, P., Haghebaert, G., & Pollet, M. 1987. Some medetera diptera dolichopodidae associated with scolytidae coleoptera from elms. Bull. Ann. Soc. R. Belge. Entomol. 123 (10-12). 380-382.

Haanstad, J.O., & Norris, D.M. 1992. Altered elm resistance to smaller european elm bark beetle coleoptera scolytidae and forest tent caterpillar lepidoptera lasiocampidae. J. Econ. Entomol. 85 (1). 172-181. ab N-ethylmaleimide in paraffin oil as a stem band and an inoculated heat-killed microbial suspension each altered Siberian and American elms regarding preference for herbivory by the forest tent caterpillar, Malacosoma disstria Hubner, and for cortical feeding by the smaller European elm bark beetle, Scolytus multistriatus Marsham. Such alteration was affected by the time after treatment, sample height in the plant, and the N-ethylmaleimide concentration. LG EN.

Hansen, L.O., & Somme, L. 1994. Cold hardiness of the elm bark beetle Scolytus laevis Chapuis, 1873 (Col., Scolytidae) and its potential as dutch elm disease vector in the northernmost elmforests of Europe. Journal. Of. Applied. Entomology. 117 (5). 444-450. Issn 0931-2048. ab Cold hardiness was studied in overwintering larvae of the elm bark beetle (Scolytus laevis) which is an important vector of the dutch elm disease in northern Europe. Mean SCPs were as low as -29 degree C in mid-winter and increased to -21 degree C in May. Corresponding melting points varied from -6.5 to - 0.7 degree C with thermal hysteresis freezing points 0.2-0.3 degree C lower during the winter. Glycerol was the main low molecular cryoprotectant substance. Frozen larvae became active shortly after thawing, but subsequently died or were unable to pupate at 21 degree C. In the early part of the winter supercooled larvae survived extended periods at -19 degree C but were killed at this temperature in the spring. It is concluded that cold hardiness will not be the limiting factor for the distribution of the elm bark beetle within the limits of the elm in Norway. LG EN.

Hanula, J.L., & Berisford, C.W. 1982. Methyl bromide fumigation destroys broods of the smaller european elm bark beetle scolytus-multistriatus coleoptera scolytidae in elm ulmus-spp logs. J. Econ. Entomol. 75 (4). 688-690. ab Methyl bromide fumigation of elm wood collected during sanitation cuttings for Dutch elm disease (Ceratocystis ulmi (Buisman) C. Moreau) control was highly effective in destroying within-tree broods of S. multistriatus (Marsham). Logs which were uninfested before fumigation were only weakly attractive to S. multistriatus, and small broods were produced. LG EN.

Hayes, A.J., & Parihar, D.R. 1987. Some observations on the breeding biology of scolytus-scolytus coleoptera scolytidae a vector of dutch elm disease in scotland uk. Arboric. J. 11 (4). 333-344.

Hildahl, V. 1977. Recognition and control of dutch elm disease in the prairie provinces. Blue. Jay. 35 (2). 67-73.

Holmes, F.W. 1980. Bark beetles ceratocystis-ulmi and dutch elm disease. Harris, K. F. And K. Maramorosch. Vectors Of Plant Pathogens. Xiv+467p. Academic Press, Inc.: New York, N.y., Usa; London, England. Illus. Maps. Isbn 0-12-326450-2. 0 (0). P133-148.

Hostetler, B.B., & Brewer, J.W. 1976. Translocation of cacodylic-acid in dutch elm diseased american elms and its effect on scolytus-multistriatus coleoptera scolytidae. Can. Entomol. 108 (8). 893-896. ab Cacodylic acid was injected into hatchet-made frill girdles 60 cm above the ground on Dutch elm-diseased (Ceratocystis ulmi (Busim.) C. Moreau) American elms (Ulmus americana L.) at the rate of 0.8 ml/cm circumference measured 1.3 m above the ground. Cacodylic acid was translocated up the trees into the phloem. Arsenic residue analyses at several different heights in each tree indicated an inverse relationship between height and amount of cacodylic acid residue in the phloem. Largest amounts were translocated in trees with 75% wilted crowns. Cacodylic acid injection into elms had no significant inhibitory effect on Scolytus multistriatus (Marsham) brood development. Cacodylic acid residues as high as 1700 ppm caused little or no beetle mortality. Highest numbers of beetles/dm2 bark surface area emerged from acid-treated elms with 75% crown wilt and from untreated elms with 100% crown wilt.

Hunt, D.J., Hague, N.& G., M. 1974. The distribution and abundance of parasitaphelenchus-oldhami a nematode parasite of scolytus-scolytus and scolytus-multistriatus the bark beetle vectors of dutch elm disease. Plant. Pathol. 23 (4). 133-135.

Jassim, H.K., Foster, H.A., & Fairhurst, C.P. 1990. Biological control of dutch elm disease bacillus-thuringiensis as a potential control agent for scolytus-scolytus and scolytus-multistriatus. J. Appl. Bacteriol. 69 (4). 563-568. ab The effects of exposing fifth instar larvae of Scolytus scolytus and S. multistriatus to spore suspensions of Bacillus spp. were investigated. Bacillus thuringiensis ser 3a, 3b increased the mortality of larvae cultured on an artificial medium from approximately 20% in control cultures to over 80% in cultures exposed to the bacteria. The mortality was dose-dependent for S. multistriatus and the appropriate LC50 value was 2.2 .times. 103 spores/ml. Different serotypes of B. thuringiensis caused different levels of mortality: H6 produced the highest mortality and H1 the lowest. Bacillus alvei and B. cereus were also pathogenic but B. megaterium was not. The results are discussed in relation to the mechanism of pathogenicity and the potential for the use of B. thuringiensis for the control of the vectors of Dutch elm disease. LG EN.

Jassim, H.K., Foster, H.A., & Fairhurst, C.P. 1990. Biological control of dutch elm disease larvicidal activity of trichoderma-harzianum trichoderma-polysporum and scytalidium-lignicola in scolytus-scolytus and scolytus-multistriatus reared in artificial culture. Ann. Appl. Biol. 117 (1). 187-196. ab A method is described for the culture of larvae of Scolytus multistriatus and Scolytus scolytus on an artificial medium following exposure to cultures of microorganisms. In control cultures, a natural mortality rate of 21.2% was found for S. multistriatus and 17.6% for S. scolytus. The effects of Trichoderma harzianum, T. polysporum and Scytalidium lignicola on fifth instar larvae of S. scolytus and S. multistriatus reared on the artificial medium were studied. The fungi were larvicidal and larval mortality was increased to more than 80% by inoculation of the larvae with the fungi. Another fungus, Phomopsis oblonga, had little effect on larvae of S. scolytus. The results are discussed in relation to mechanism of pathogenicity of the fungi and their potential use in the control of Dutch elm disease. It is proposed that with modifications, the method is applicable to other bark beetle pests. LG EN.

Jenkins, P. 1994. Dutch elm disease-contingency plan. Plant. Protection. Quarterly. 9 (2). 59-60. Issn 0815-2195.

Jin, H., Webster, G.& R., B. 1997. Persistence, penetration, and surface availability of chlorpyrifos, its oxon, and 3,5,6-trichloro-2-pyridinol in elm bark. Journal. Of. Agricultural. And. Food. Chemistry. 45 (12). 4871-4876. Issn 0021-8561. ab The persistence, penetration, and bark surface contact availability of chlorpyrifos and its main degradation products, the oxon and 3,5,6-trichloro-2-pyridinol, in elm bark were investigated after chlorpyrifos had been applied to the basal 1 m of elm tree trunks for control of overwintering elm bark beetles, the vector of Dutch elm disease, at different application times and sites. The initial residues of chlorpyrifos in elm bark were 388-444 mu-g/g. The initial chlorpyrifos residues dissipated quickly with half-lives of 1.1-2.9 days for the faster dissipation phase. The dissipation of chlorpyrifos during the later period became much slower, with the dissipation half-lives ranging from 205 to 228 days. No penetration of chlorpyrifos into the cambium layer and wood tissue was found during the experimental period of 791 days. In the contact test, the chlorpyrifos residues transferred from the treated bark during a 1-min contact were below the acceptable daily intake for humans immediately following drying of the treated bark and diminished over the period of the experiment. LG EN.

Jin, H., Webster, G.R., B., Holliday, N.J., Pines, P.A., & Westwood, A.R. 1996. An elm bark beetle bioassay for residual efficacy of chlorpyrifos and cypermethrin used for the control of Dutch elm disease in Manitoba. Journal. Of. Environmental. Science. And. Health. Part. B. Pesticides. Food. Contaminants. And. Agricultural. Wastes. 31 (4). 751-761. Issn 0360-1234. ab The basal 1 m of the elm trunks were treated with 0.48% (active ingredient, Al) Dursban aqueous solution (chlorpyrifos) or 0.1% (Al) Ripcord aqueous solution (cypermethrin) for control of overwintering native elm bark beetle, Hylurgopinus rufipes, the vector of Dutch elm disease, Ophiostoma (Ceratocystis) ulmi, at Beaudry Provincial Park, near Winnipeg, Manitoba, Canada. A simple and effective bioassay method was developed to determine insecticidal persistence against the native elm bark beetle. Beetles reared in naturally infested elm logs were confined to the surface of elm bark circles taken from the treated trees. Bark circles were cut at various times after treatment using a cordless hole saw and stored at -32 degree C until the beetles were available. Mortality/morbidity data for the two treatments were suitable for use in the comparison of the action of the two insecticides over a two-year period. LG EN.

Jin, Lin, S., & Fang, C. 1990. Breeding behavior of the bark beetle scolytus-schevyrewi semenov coleoptera scolytidae in ulmus-pumila. J. Appl. Entomol. 109 (5). 528-530. ab Scolytus schevyrewi beetles were caged on the stems of both wilting and healthy trees, but breeding was successful only on the wilting elms. The possibility that this scolytid species could act as a vector of Dutch elm disease in China is discussed. LG EN.

Jumper, G.A., Cannon, W.& N., JR. 1976. Chromosome number in the smaller european elm bark beetle scolytus-multistriatus. Ann. Entomol. Soc. Am. 69 (3). 500-502. ab Prepupal testicular tissues of S. multistriatus (Marsham) (vector of Dutch elm disease) were examined. The chromosome complements of the meiotic cells have a haploid number of 6.

Karnosky, D.F. 1979. Dutch elm disease a review of the history environmental implications control and research needs. Environ. Conserv. 6 (4). 311-322.

King, C.J., & Scott, T.M. 1975. Testing dosage rates of methoxychlor applied by helicopter for control of dutch elm disease. Forestry. Oxf. 48 (2). 177-181.

Kirby, S.G., & Fairhurst, C.P. 1981. Hope for the elm 1. towards an understanding of the biology and ecology of elm bark beetles in northern england uk. Arboric. J. 5 (4). 243-249.

Lagrange, A., Olesker, A., Costa, S.S., Lukacs, G., & Thang, T.T. 1982. A route from d galactose to the aggregation pheromone component levo-alpha multistriatin. Carbohydr. Res. 110 (1). 159-164.

Lanier, G.N. 1982. Dutch elm disease a postscript. Arnoldia. Boston. 42 (2). 78-87.

Lanier, G.N. 1989. Trap trees for control of dutch elm disease. J. Arboric. 15 (5). 105-111.

Lanier, G.N., & Jones, A.H. 1985. Trap trees for elm bark beetles scolytus-multistriatus augmentation with pheromone baits and chlorpyrifos. J. Chem. Ecol. 11 (1). 11-20. ab S. multistriatus (Marsh.) were strongly attracted to American elms, Ulmus americana L., baited with the S. multistriatus attractant, multilure, or killed by injection of the arboricide, cacodylic acid; a combination of the 2 treatments was most attractive. Comparisons of beetle catches on sticky bands affixed to the trees with samples of bark from the same trees showed that the number of beetles landing on cacodylic acid-treated trees was approximately 40 times greater than the number boring into them. Spraying the bark with the insecticide chlorpyrifos had no direct effect on attraction. No live bark beetle brood was found in trees that had been treated with cacodylic acid or chlorpyrifos, but trees that were only baited or left untreated (check) were attacked, killed, and colonized. The contribution of the cacodylic acid trap tree technique to Dutch elm disease control (Ceratocystis ulmi) will be enhanced by baiting treated trees with multilure and spraying their lower boles with 0.5% chlorpyrifos. This treatment will eliminate diseased and unwanted elms at potential breeding material and kill large numbers of elm bark beetles that might otherwise inoculate healthy elms with the Dutch elm disease fungus. LG EN.

Lanier, G.N., Schubert, D.C., & Manion, P.D. 1988. Dutch elm disease and elm yellows in central new york usa out of the frying pan into the fire. Plant. Dis. 72 (3). 189-194.

Lanier, G.N., Silverstein, R.M., & Peacock, J.W. 1976. Attractant pheromone of the european elm bark beetle scolytus-multistriatus isolation identification synthesis and utilization studies. Anderson, John F. And Harry K. Kaya (ed.). Perspectives In Forest Entomology. Proceedings Of A Lockwood Conference On Perspectives Of Forest Pest Management. New Haven, Conn., U.s.a. ; Oct. 15-17, 1975 Xxiii+428p. Illus. Academic Press: New York, N.y., U.s.a. ; London, England. Isbn 0-12-056650-8. 149-175.

Larcheveque, M., & Henrot, S. 1987. A stereospecific synthesis of optically pure levo-alpha multistriatin. Tetrahedron 43 (10). 2303-2310. ab An efficient stereo- and enantiospecific synthesis of (-)-.alpha.-multistriatin from (L)-malic acid is described. The key steps of this synthesis are the stereoselective alkylation of the hydroxylactone 5 and the acid equilibration of the esters 9 and 10. LG EN.

Laut, J.G., Helburg, L.B., & Schomaker, M.E. 1973. Dutch elm disease in colorado 1972. Plant. Dis. Rep. 57 (6). 511-513.

Lea, J., & Brasier, C.M. 1983. A fruiting succession in ceratocystis-ulmi and its role in dutch elm disease. Trans. Br. Mycol. Soc. 80 (3). 381-388. ab A distinct succession of fruiting of C. ulmi was observed within beetle breeding galleries in the bark of diseased elms between the time of beetle colonization in summer and emergence in the following spring. Mycelial conidia and synnemata were predominant in the warm period following colonization. They declined rapidly at the onset of winter, and were replaced by perithecia. The perithecia declined by the end of winter, and with the onset of higher temperatures prior to beetle emergence there was a resurgence of the mycelial conidia. Two periods of active growth of C. ulmi were indicated, one following beetle colonization and the other in the spring. The succession is governed largely by temperature and nutrients and provides a secondary inoculum which asists in early colonization of the bark and a tertiary resting inoculum which enables the fungus to survive the winter and recolonize the bark in the spring. LG EN.

Lyons, D.B. 1982. The morphology of the stridulatory structure of hylurgopinus-rufipes coleoptera scolytidae and the use of stridulation to sex live adults. Proc. Entomol. Soc. Ont. 113 (0). (1983). 53-58. ab The morphology of the stridulatory structures and the distress-related stridulatory behavior of males of H. rufipes (Eichhoff) (the vector of Dutch elm disease) are described. Sexing newly emerged adults on the basis of stridulation movements was 99.5% accurate. For stored adults, sexing by this method was significantly less accurate. Errors in sexing resulting from failure of some males to stridulate and not from stridulation movements in females. LG EN.

Maksimovic, M. 1979. Influence of the density of bark beetles and their parasites on dieback of elm in some woods of yugoslavia. Z. Angew. Entomol. 88 (3). 281-295. ab The vectors of Dutch elm disease Scolytus multistriatus Mrsh. and S. scolytus F. are the principle factors in the progress of dieback. Of less importance are S. pygmaeus F. and Pteleobius kraatzi Ech. Their density depends on composition and state of the wood, frequency of natural enemies especially parasites, climatic factor and internal resistance of the tree. No difference occurs in the population distribution of the bark beetles on the tree between the 1st and 2nd generation, except in young wood with maximum diameter of 15 cm, where the 2nd generation occupied habitats 1.5-5 m lower than the 1st. Most parasitization of bark beetles is by 4 spp., i.e., the hymenopterans Dendrosoter protuberans Nees, followed by Ecphylus silesiacus Ratz., Coeloides scolyticida Wesm. and (as an egg parasite) Entedon leucogramma Ratz. The higher humidity and lower temperature in western Yugoslavia checks the density of bark beetles, thereby slowing down the rate of dieback from Dutch elm disease. LG EN.

Maksimovic, M., & Motal, Z. 1983. Influence of sanitary measures on the dying of elm trees caused by dutch elm disease and the attack of bark beetles. Z. Angew. Entomol. 96 (4). 327-332. ab In a mixed forest Cesma in Salvonija (Yugoslavia) a 3-yr study was made on the application of sanitary measures elm trees dying from attack of bark beetles (mainly Scolytus multistriatus Marsh., S. scolytus F., S. pygmaeus F. and Pteleobius kraatzi Eichh.) and the Dutch elm disease (Ceratocystis ulmi (Buis.) Moreau). Felling of the attacked elm trees began in June and at the beginning of Sept. The trunk and branches were treated immediately with oil preparation of the insecticide (xyloline). A complete cessation of tree death was achieved in the fourth yr. LG EN.

Maksimovic, M., Motal, Z., Bartovcak, D., & Drndelic, M. 1971. A contribution to the study of elm dieback caused by dutch elm disease in the region of forest farm bjelovar. Zast. Bilja. 22 (112-113). 3-20.

Maloy, O.C., & Inglis, D.A. 1978. Dutch elm disease in washington usa. Plant. Dis. Rep. 62 (2). 161-164. ab Dutch elm disease caused by Ceratocystis ulmi was observed on 2 elm trees in an advanced state of wilting and with browning foliage. A mature beetle, probably the vector, was found on a branch and identified as Scolytus multistriatus. LG EN.

Manojlovic, B. 1986. A contribution of the study of the development of the smaller elm bark beetle scolytus-multistriatus marsh. Zast. Bilja. 37 (3). 251-270. ab The object of the study was the development of the smaller elm bark beetle Scolytus multistriatus Marsh. under the conditions prevailing in our country. A particular attention has been paid to the diapause, egg-laying capacity and complementary nutrition. The smaller elm bark beetle is the most important vector of the fungus Ceratocystis ulmi Moreau (Buis), causer of the so-called "Dutch disease" on the elm-tree. In the central parts of Yugoslavia it chiefly hibernates in the larval stage, most frequently from the second generation that did not succeed in concluding the development in autumn or remained in the diapause from the first generation. In our conditions they can hibernate as pupae and imagos, which depends from the period of time, in which stage the elm bark beetle population found itself when the low autumn temperatures began, interrupting the development of bark beetles. The swarming period of imagos of S. multistriatus takes place in our country in the couse of May and in the first half of June, as well as at the end of July and in the first half of August in the second generation. The flying out of insects after the development of the first generation had been concluded, lasted 43 days in 1971 and 48 days in 1972. After the complementary feeding of imagos, which is performed in the furcate twigs of the elm-tree from 1 to 5 years old, there begins the piercing in and the deposition of eggs. Imagos of S. multistriatus bore into the bark of the elm tree, where the turgor had slackened. The most appropriate parts of the trunk for the boring in are those whose diameter is about 12 cm and the thickness of the bark about 7 cm, although it develops also in the trunks where the thickness of the bark is over 12 mm as well as on the branches where the bark is only 3 mm thick. The results point out that under the conditions of the laboratory the total laying-egg capacity of the females varied, in 1971, from 19 to 57 eggs (35 eggs on an average), and in 1972 from 24 to 65 eggs (40 eggs on an average), whereas the number of larval galleries under natural conditions amounted to an average of 51.9 in 1971, resp. 49.8 in 1972. At the constant temperature of and at 75 p.c. of relative humidity, the embryonal development of eggs lasts from 4 to 16 days, 6 days on an average; the larval stage lasts

Marinos, M.G., & French, D.W. 1971. Dutch elm disease in minnesota 1970. Plant. Dis. Rep. 55 (8). 682-683.

Michalski, J. 1976. Sex ratio of some chalcids hymenoptera chalcidoidea parasitizing scolytus-ssp coleoptera scolytidae during the development of the host generation. Pol. Pismo. Entomol. 46 (1). 3-16. ab Studies are important for determining the practical role of a parasite and its presence in a given biotype; if phenologically approached these studies may also provide the main data on the development of the biocenosis components in respect of the insurance of the developmental optimum for the same parasites. Of the Hymenoptera parasitizing Scolytus, the following most common and widespread species deserve special attention: Cheiropachus colon (L.) , Rhaphitelus maculatus Walk., Entedon leucogramma (Ratz.), Ecphylus silesiacus (Ratz.), Coeloides scolyticida Wesm. and species of the genus Eurytoma Ill. Of particular importance is the estimation of the influence of some parasite species on the density of their host populations. Especially desirable in this respect is the coordination of such studies on an international level within a complex protection program against damage caused by Dutch elm disease, which at present is a problem throughout the world. There is a need for a complete juxtaposition, confrontation and correction of the information on the ecology, biology and practical importance of parasitic Hymenoptera, since the information in the literature is often incomplete, doubtful and contradictory.

Millar, J.G., Zhao, C.H., Lanier, G.N., O.Callaghan, D.P., Griggs, M., West, J.R., & Silverstein, R.M. 1986. Components of moribund american elm ulmus-americana trees as attractants to elm bark beetles hylurgopinus-rufipes and scolytus-multistriatus. J. Chem. Ecol. 12 (3). 583-608. ab Hylurgopinus rufipes male and female beetles and attracted to American elms infected with Dutch elm disease, and to American elms killed by injection of cacodylic acid, H. rufipes was also attracted to solvent extracts of elm, or to Porapak Q-trapped volatiles from elm. The major components of attractive fractions of Porapak Q-trapped volatiles were isolated, identified, and tested in field bioassays. Several artificially compounded mixtures of sesquiterpenes were attractive to H. rufipes, although no bait tested was as attractive as diseased tree controls. Laboratory bioassays with H. rufipes were marginally successful. In laboratory bioassays, nine of 14 sequiterpenes identified from active fractions of Porapak extracts elicited significant response from Scolytus multistriatus male and female beetles: .delta.- and .gamma.-cadinene, .alpha.-cubebene, .gamma.-muurolene, and .beta.-elemene were most active. However, in field tests, none of the sesquiterpenes alone or in combination significantly attracted S. multistriatus, nor did they significantly enhance the attraction of S. multistriatus to female-produced pheromone components (4-methyl-3-heptanol (H) and .alpha.-multistriatin (M)). In other field tests, .alpha.-cubebene (C) significantly enhanced response of S. multistriatus to H plus M, but foliage, logs, or chips of healthy elm did not enhance trap catch to HMC. LG EN.

Neely, D. 1984. Dutch elm disease control in illinois usa municipalities. Plant. Dis. 68 (4). 302-303. ab Twenty-one cities in the greater Chicago area in Illinois continue to monitor and report losses of elms in parkways after application of disease control techniques. Cumulative losses (due to Ceratocystis ulmi) during 1957-1982 ranged 35-84%. Annual losses in cities that applied insecticides (to control Scolytus multistriatus) supplemental to sanitation procedures averaged 1-1.5% lower than in cities that used sanitation alone. LG EN.

O & Callaghan, D.P. 1982. Occurrence of the small elm bark beetle scolytus-multistriatus in ireland. Ir. Nat. J. 20 (9). 384-385.

O Brien, J.G., & Blanchette, R.A. 1984. Fungal colonization of moribund american elm tissues. 1984 Annual Meeting Of The Phytopathological Society, Ontario, Canada, Aug. 12-16, 1984 Phytopathology 74 (7). 870.

O Callaghan, D.P., & Atkins, P.M. 1981. Hope for the elm 2. towards an integrated control program for the dutch elm disease. Arboric. J. 5 (4). 250-256.

O Callaghan, D.P., Atkins, P.M., & Fairhurst, C.P. 1984. Behavioral responses of elm bark beetles to baited and unbaited elms killed by cacodylic-acid. J. Chem. Ecol. 10 (11). 1623-1634. ab Diseased elms, treated with various doses of cacodylic acid in northwest England (UK) became attractive to elm bark beetles (Scolytus scolytus and S. multistriatus) (Coleoptera: Scolytidae). This attraction seemed to be independent of pheromone baits. However attractive the trees became, they were unsuitable to the beetles as breeding sites since significantly more beetles visited the trees than were stimulated to penetrate and attempt to breed. It seems as if colonization of trap trees by the bark saprophyte Phomopsis oblonga following cacodylic acid treatment made the trees unsuitable to beetles for breeding. LG EN.

O Callaghan, D.P., Gallagher, E.M., & Lanier, G.N. 1978. Field evaluation of pheromone baited trap trees to control elm bark beetles. J. N. Y. Entomol. Soc. 86 (4). 312.

O Callaghan, D.P., Gallagher, E.M., & Lanier, G.N. 1980. Field evaluation of pheromone baited trap trees ulmus-americana to control elm bark beetles vectors of dutch elm disease ceratocystis-ulmi. Environ. Entomol. 9 (2). 181-185. ab Over 250 diseased or unwanted elm trees (U. americana) were killed with the herbicides cacodylic acid (Silvisar 510) or MSMA (Silvisar 550) (monosodium methanearsonate), applied either to axe-frills or by pressure injection. Elms thus poisoned and baited with the pheromone multilure, were mass-attacked by elm bark beetles (Scolytus multistriatus and Hylurgopinus rufipes) but > 87% of the potential brood was effectively eliminated. A decline in the Dutch elm disease rate accompanied brood elimination. This trap tree technique will make a positive contribution to Dutch elm disease control programs by enhancing existing sanitation procedures and allowing tree removal to proceed in an orderly manner, rather than on the urgent schedule now necessary to prevent new infections vectored by emerging beetles. LG EN.

Ouellette, G.B. 1984. Results of an intensive prevention program against dutch elm disease in the regions of quebec and the saguenay river lake st-john canada. 76th Annual Meeting Of The Societe De Protection Des Plantes Du Quebec (quebec Society For The Protection Of Plants), Saint. Marc. Sur. Richelieu,. Quebec, Canada, June 7-8, 1984 Phytoprotection 65 (2). 93.

Pajares, J.A., & Lanier, G.N. 1989. Pyrethroid insecticides for control of european elm bark beetle coleoptera scolytidae. J. Econ. Entomol. 82 (3). 873-878. ab Commercial formulations of four pyrethroid insecticides, fluvalinate (Mavrik), permethrin (Pounce), cypermethrin (Ammo), and esfenvalerate (Asana), were 222-548 times more toxic to European elm bark beeetles, Scolytus multistriatus (Marcham), than was methoxychlor. Compared with methoxychlor, all of the pyrethroids provided superior protection from twig feeding: two products, cypermethrin and esfenvalerate, killed all beetles contacting sample twigs and prevented twig feeding through an 18-wk period of bioassays after spray. The same two compounds applied to infested elm wood killed all beetles before, or shortly after, they emerged; chlorpyrifos also caused 100% mortality of beetles emerging from brood wood, but its action was not as rapid. The pyrethroids tested could increase the effectiveness of spraying elm crowns to prevent Dutch elm disease. They also could be used to eliminate elm bark beetles as they emerge from brood wood or land on treated surfaces baited with attractants. Potency and durability combined with their low risk to birds and mammals give the pyrethroids excellent potential for the control of other tree pest insects. LG EN.

Parbery, D.G., & Rumba, K.A. 1991. Michenera-artocreas new-record in elm wood infested with scolytus-multistriatus in australia. Mycol. Res. 95 (6). 761-762.

Parihar, D.R., & Hayes, A.J. 1987. Biology of scolytus-laevis chapuis coleoptera scolytidae a vector of dutch elm disease in scotland uk. Scott. For. 41 (3). 185-196.

Patridge, A.D., & Miller, D.L. 1972. Dutch elm disease continues to move east in the idaho oregon area. Plant. Dis. Rep. 56 (11). 939.

Peacock, J.W. 1975. Research on chemical and biological controls for elm bark beetles. Burdekin, D. A. And H. M. Heybroek. Dutch Elm Disease. Proceedings Of The International Union Of Forest Research Organizations. Minneapolis. St.. Paul, Minn., U.s.a. Sept. 1973 1-94p. U. S. Department Of Agriculture Forest Service, Northeastern Forest Experiment Station: Upper Darby, Pa., U.s.a. 18-49.

Phillipsen, W.J., Ascerno, M.E., & Landwehr, V.R. 1986. Colonization emergence and survival of hylurgopinus-rufipes and scolytus-multistriatus coleoptera scolytidae in insecticide-treated elm ulmus-americana wood. J. Econ. Entomol. 79 (5). 1347-1350. ab Application of 0.1, 0.25, 0.5% (AI) chlorpyrifos, 2.0% (AI) carbaryl, or 0.1% (AI) permethrin to cut elm, either before or after gallery formation, significantly reduced brood production of Scolytus multistriatus (Marsham), the smaller European elm bark beetle, and Hylurgopinus rufipes (Eichhoff), the native elm bark beetle. Bioassays and residue analyses of treated elm, Ulmus americana L., showed that 0.5% (AI) chlorpyrifos was present and active for at least 11 months, thus providing ample time for cut elm to reach a point at which it was no longer suitable for beetle breeding. Application of 0.5% (AI) chlorpyrifos makes possible the long-term storage of undebarked, cut elm in a manner that is compatible with ongoing Dutch elm disease control programs. LG EN.

Piccardi, P. 1980. Insect sex communication and prospects for pheromones in pest management. Symposium On Applied Zoology, Bergamo, Italy, Sept. 5, 1979 Boll. Zool. 47 (3-4). (1981) 397-408.

Pines, I.L., & Westwood, A.R. 1996. Evaluation of monosodium methane arsenate for the suppression of native elm bark beetles, Hylurgopinus rufipes (Eichhoff) (Coleoptera: Scolytidae). Canadian. Entomologist. 128 (3). 435-441. Issn 0008-347x. ab The native elm bark beetle, Hylurgopinus rufipes (Eichhoff), is the major vector of Dutch elm disease, Ophiostoma ulmi (Buisman) Nannf., in Manitoba. The herbicide Glowon, monosodium methane arsenate (MSMA) , was applied to a chainsaw cut in American elm, Ulmus americana L., tree stems to determine if the treated elms would become effective trap trees for H. rufipes. Three treatments were compared: treated with herbicide and girdled, girdled, and control. All herbicide-treated elms died within 18 days after application. Significantly higher numbers (P lt 0.01) of native elm bark beetles were attracted to the herbicided elms, compared with the other treatments. Beetles bred only in the elms treated with herbicide. Of the total brood galleries constructed, 72% had no egg hatch while the remaining 28% had larval tunnels. Progeny adults emerged from less than 1% of the larval tunnels. MSMA application could supplement the Dutch elm disease management program in Manitoba. LG EN.

Rabaglia, R.J., & Lanier, G.N. 1984. Twig feeding by scolytus-multistriatus coleoptera scolytidae within tree distribution and use for assessment of mass trapping. Can. Entomol. 116 (7). 1025-1032. ab Twig-feeding injuries by S. multistriatus in juvenile white (or American) elms occurred primarily (61%) in the upper 1/3 of the crowns. Preferred feeding sites were crotches formed by the previous year's and current year's twig growth (both spring and summer) and by leaf petioles from current year's twig growth (summer only). An index of twig feeding appeared to reflect S. multistriatus population trends and was closely correlated with Dutch elm disease (Ceratocystis ulmi) rates in Syracuse, (New York, USA) from 1978-1982. Twig-feeding indices and catches on sticky traps baited with S. multistriatus pheromone were generally correlated, but disparate when competing natural pheromone sources were abundant. Twig sampling indicated that S. multistriatus populations and disease rates were reduced by mass-trapping and trap-tree techniques. The twig-sampling method presented appears to be useful in predicting Dutch elm disease rates and assessing the effectiveness of measures to control its beetle vector. LG EN.

Rexrode, C.O. 1974. Effect of pressure injected oxydemeton-methyl cacodylic-acid and 2 4-d amine on elm bark beetle populations in elms infected with dutch elm disease. Plant. Dis. Rep. 58 (4). 382-384.

Richards, N.T. 1988. Mycotechnology trichothecin revisited. Mycologist 2 (3). 123-124.

Sacchetti, P., Tiberi, R., & Mittempergher, L. 1990. Preference of scolytus-multistriatus marsham in twig-crotch feeding on two elm species. Redia 73 (2). 347-354. ab As elm bark beetles are the most important vectors in spreading Dutch elm disease, the feeding preference of Scolytus multistriatus (Marsham) adults on Ulmus carpinifolia Gled. and U. laevis Pallas was investigated. Newly emerged adults were introduced into a net tent containing 8 trees 4 years old for each species. The results show the beetles' preference for U. carpinifolia. In fact the mean number of feeding grooves cut on U. carpinifolia was four times higher than that recorded on U. laevis. LG IT.

Schacherl, E. 1996. The native elm bark beetle: Primary vector of Dutch Elm disease in Saskatchewan. Blue. Jay. 54 (3). 147-151. Issn 0006-5099.

Scheffer, R.J. 1989. Pseudomonas for biological control of dutch elm disease iii. field trials at various locations in the netherlands. Neth. J. Plant. Pathol. 95 (6). 305-318. ab The prophylactic effect in elm of one treatment with a Pseudomonas isolate was monitored in two types of field trials. In one type only natural Dutch elm disease infections were monitored and hence large numbers of trees were necessary due to the low incidence of natural occurring infections. In the other type trees were artificially infected. The large-scale field trials in which only natural infections were monitored, were based on expected annual losses due to Dutch elm disease of approximately 2%. As a result of the Dutch sanitation program, which was based on the prompt removal of every weakened or diseased elm, the actual losses were generally threefold lower. Dutch elm disease incidence was 22-45% lower in the trees treated with a Pseudomonas isolate in the year of treatment and the year after. The results of the biocontrol treatment were negatively influenced because on several locations trees were felled that showed initial signs of Dutch elm disease, which probably would have disappeared during the season. The advantage of artificial infections with Ophiostoma ulmi was a reproducable development of symptoms and the possibility to maintain disease trees, at least till the first signs of elm bark beetle breeding. For 'Commelin' elms (Ulmus x hollandica) an increase in symptoms was observed with increasing O. ulmi dose till 3000 conidia per tree; the standard 500 000 conidia used for most experiments was well above this critical value. No decrease in effectiveness of the bacterial pre-treatment was observed with increasing O. ulmi inoculum. Different bacterial treatments suggested that injections at a smaller interval (i.e. more injections per tree) may result in a better prophylactic effect, but the significance of the correlation remained doubtful. A comparison of several elm species and clones showed that importance of the host tree. Prophylaxis as a result of one bacterial treatment was shown repeatedly in 'Commelin' elms; the numbers of trees showing symptoms by the end of the second year were 10 to 85% lower in the bacteria-treated groups in comparison with the controls. Also in one experiment with 'Belgica' elms prophylaxis was observed, resulting in a 84% decrease in the number of trees showing symptoms by the end of the second year after the prophylactic treatment followed by inoculation with O. ulmi. In

Schlyter, F., Anderbrant, O., Lindquist, G., & Jansson, A. 1987. Dutch elm disease ceratocystis-ulmi and elm bark beetles scolytus-spp in malmo town sweden 1985 distribution phenology and practical measures in an integrated control program. Vaxtskyddsnotiser 51 (1). 2-10. ab Elms and Dutch elm disease (DED) were surveyed in winter 1984/85. The aggressive DED strain was shown to be established and 23,666 elms were mapped on publicly owned ground. Of the seven forms of elm recognized, Ulmus glabra was the most common, followed by U. carpinifolia "Horsholmii" and U. carpinifolia var. sarniensis. During the winter 450 elms in poor condition were cut. Following an extensive survey scheme during the summer, 300 elms, mostly U. glabra, were cut and destroyed as they had DED or served as brood trees for elm bark beetles. Both the aggressive strain of DED and elm bark beetles were found over the whole city. 100 sticky traps baited with 4-methyl-3-heptanol were used to catch elm bark beetles and caught low numbers of Scolytus scolytus and S. laevis on a number of sites across the city between June and September. S. multistriatus and S. rugulosus were trapped at one site each. Recommendations are given for the monitoring (elm surveys, pheromone traps) and control (destruction of infested trees) of DED and its vectors. LG SS.

Schroeder, D. 1974. Studies on the possibilities of biological control of elm bark beetles scolytidae with the view of reduction of the dutch elm disease. Z. Angew. Entomol. 76 (2). 150-159.

Sengonca, C., & Leisse, N. 1984. Significance of bark beetles coleoptera scolytidae in the spread of the dutch elm disease in the area of euskirchen west germany. Z. Angew. Entomol. 98 (4). 413-423. ab In the area of Euskirchen the bark beetles Scolytus scolytus F., S. multistriatus Marsh, S. pygmaeus F., Pteleobius vittatus Eichhoff and P. kraatzi Eichhoff were found to be vectors of the Dutch elm disease (caused by Ceratocytis ulmi (Buis.)). In stands of older elm trees S. scolytus was dominant, whereas in younger tree stands, S. multistratus was found most frequently S. pygmaeus, P. vittatus, and P. kraatzi wereonly of minor importance. Daily temperatures below C delayed development and influenced the behavior of S. scolytus and S. mulitstriatus. The higher insolation on the southern sides of the trees accelerated development. Elm trees that were infested with feeding bark beetles showed the 1st symptoms after a few days. The disease can be transmitted by the feeding of 1 bark beetle. Progress of the disease was observed. In the beginning of the investigations, only younger tree stands were healthy; 81.8% of elm trees younger than 20 yr were healthy, whereas 91% older than 60 yr had died already. Therefore, it appeared that old elm trees were preferred by bark beetles. In 1983 only a high increase in the infestation of younger elm trees was noticed. LG GE.

Smalley, E.B., & Guries, R.P. 1993. Breeding elms for resistance to dutch elm disease. Cook, R. J. (ed.). Annual Review Of Phytopathology, Vol. 31. X+551p. Annual Reviews Inc.: Palo Alto, California, Usa. Isbn 0-8243-1331-3. 0 (0). 325-352.

Sticklen, M.B., Bolyard, M.G., Hajela, R.K., & Duchesne, L.C. 1991. Molecular and cellular aspects of dutch elm disease. Phytoprotection 72 (1). 1-14.

Stillwell, M.A. 1977. Micro flora associated with elm bark beetle feeding niches suggests biological control of dutch elm disease. Can. For. Serv. Bi. Mon. Res. Notes. 33 (3). 20.

Svihra, P., & Koehler, C.S. 1981. Attraction of flying scolytus-multistriatus to cut wood of 3 elm species in california usa. Environ. Entomol. 10 (4). 565-566. ab S. multistriatus (Marsham) (vector of the Dutch elm disease Ceratocystis ulmi (Buism.)) was significantly more attracted to bolts freshly cut from Ulmus procera Salisb., than to U. pumila L. and U. parvifolia Jacq. and unbaited controls in a pure stand of U. procera. Beetle attraction to U. parvifolia was significantly lower than to U. procera and U. pumila and did not differ from that of unbaited controls. In contrast, the response of beetles to bolts of U. procera and U. pumila was not significantly different in a pure stand of U. pumila. LG EN.

Svihra, P., & Koehler, C.S. 1982. Attack and development of scolytus-multistriatus in small diameter elm branches. Environ. Entomol. 11 (3). 594-597. ab S. multistriatus attack density, gallery length and brood production beneath the bark of Ulmus procera branches 2-6 cm in diameter increased as branch diameter increased. Beetles did not complete development in 2-cm-diameter branches, and an average of 70 beetles /dm2 emerged from 6-cm-diameter branches. Removal of small-diameter, moribund branches above 2-cm in diameter may be necessary if all potential breeding sites are to be eliminated in Dutch elm disease (Ceratocystis ulmi (Buism) C. Moreau) prevention programs. LG EN.

Takai, S., & Kondo, E.S. 1972. Seasonal changes in susceptibility of white elm trees to dutch elm disease in central ontario. Proc. Can. Phytopathol. Soc. 39. 42.

Takai, S., Kondo, E.S., & Thomas, J.B. 1979. Seasonal development of dutch elm disease on white elms in central ontario canada part 2 following feeding by the north american native elm bark beetle. Can. J. Bot. 57 (4). 353-359. ab Adults of the North American native elm bark beetle, Hylurgopinus rufipes, naturally infested with Dutch elm disease fungus, Ceratocystis ulmi, were caged on trunks of white elms (Ulmus americana) so that infection could be studied. In surveys made in 1971, expression of external symptoms of Dutch elm disease was observed on elms which had been caged with beetles during the period May 26-July 9, 1971. Vascular discoloration (internal symptom expression), fungus spread, fungus contamination of beetles and transmission of fungus to the host by beetles were pronounced on elms caged with beetles from June 3-July 2. C. ulmi was recovered from leaves of trees caged during the period May 26-July 2. Until May 31, 1972, dieback and death resulting from infection were restricted to trees caged with beetles during June. Corresponding development of vascular discoloration and fungus spread in the host also occurred, mostly during the caging period in June. There was no appreciable change in beetle activity in xylem tissue during the experiment period. The period of highest susceptibility of white elm to Dutch elm disease in 1971 in central Ontario was probably June 3-July 2. Inoculation through feeding by caged beetles carrying C. ulmi is probably the method that most closely approximates natural infection. LG EN.

Thomas, J.B. 1971. Smaller european elm bark beetle found in sault-ste-marie ontario. Can. -dep. Fish. Forest. -bi. Mon. Res. Notes. 27 (1). 3.

Tomalak, M., Welch, H.E., & Galloway, T.D. 1988. Interaction of parasitic nematode parasitaphelenchus-oldhami nematoda aphelenchoididae and a bacterium in dutch elm disease vector hylurgopinus-rufipes coleoptera scolytidae. J. Invertebr. Pathol. 52 (2). 301-308. ab The bark beetle, Hylurgopinus rufipes, an important Dutch elm disease vector, was infected with a Gram-negative, rod-shaped bacterium observed in all stages of the host's development. Large aggregations of this apparently innocuous bacterium were found in the fat body, the cytoplasm of the tropharia of the ovaries, and later in the developing eggs. Bacterial cells were localized in isolated pockets in the tissues. An apparent synergistic effect of a concurrent infection by the bacterium and the nematode, Parasitaphelenchus oldhami led to the rupture of cell membranes by the nematodes and dispersal of bacteria throughout the hemocoel. Subsequent depletion of the fat body tissue in the host was rapid. Juvenile (L3) P. oldhami invaded teneral adults and developed rapidly during the first 5-6 days. A substantial decrease in the prevalence and intensity of nematode infection in adult H. rufipes was observed prior to and during hibernation. LG EN.

Walker, C. 1973. Interception of the north american native elm bark beetle hylurgopinus-rufipes imported from canada into britain in logs of rock elm ulmus-thomasii. Plant. Pathol. 22 (3). 147.

Walker, C., & Ross, R. 1975. A comparison of maturation feeding of the elm bark beetles scolytus-scolytus and scolytus-multistriatus on english elm ulmus-procera and 6 other elm taxa. Plant. Pathol. (lond) 24 (4). 187-191. ab In labotatory experiments, the beetles were allowed to choose between English elm and one of 6 other taxa (Smooth-leaved, Wheatley, Wych, Huntingdon, Commelin 274 and Cornish) for maturation feeding. Preference was sometimes shown for English elm over Huntingdon and Commelin elms and, on one occasion, Wheatley elm was fed on more than English. However, there was no consistent pattern. Sufficient feeding occurred on all taxa to enable spores of the Dutch elm disease fungus (Ceratocystis ulmi) to be introduced to the twigs.

Webber, J. 1981. A natural biological control of dutch elm disease. Nature. Lond. 292 (5822). 449-451.

Webber, J.F. 1990. Relative effectiveness of scolytus-scolytus scolytus-multistriatus and scolytus-kirschi as vectors of dutch elm disease. Eur. J. For. Pathol. 20 (3). 184-192. ab Throughout Spain and Portugal three species of bark beetle, Scolytus scolytus, S. multistriatus and S. kirschi were found to be consistently associated with both agressive and non-aggressive subgroups of the Dutch elm disease pathogen, Ophiostoma ulmi. However, the species varied considerably in their effectiveness as vectors of O. ulmi, both in the proportion of beetles found to carry the fungus following emergence from breeding material, and in the number of spores present on any one individual beetle. Of the beetles carrying an inoculum of O. ulmi, spore loads ranged from 0-350000 for S. scolytus individuals, 0-57000 for S. multistriatus, and 0-300 for S. kirschi. It is concluded from these results that successful disease transmission via maturation feeding occurs most frequently with S. scolytus, is rare or never occurs with S. kirschi, while S. multistriatus is a poor to moderate vector of O. ulmi. LG EN.

Webber, J.F., & Gibbs, J.N. 1984. Colonization of elm bark by phomopsis-oblonga. Trans. Br. Mycol. Soc. 82 (2). 348-352.

Zanta, F., & Battisti, A. 1989. Notes on the distribution and biology of the elm bark beetles in northeastern italy coleoptera scolytidae. Gortania. Atti. Mus. Friulano. Stor. Nat. 11 (0). (1990). 189-206. ab In North-eastern Italy (Veneto and Friuli-Venezia Giulia) nine species of elm bark beetles, known as vectors of the fungus causing the Dutch elm disease, have been recorded. The life history, distribution and ecological requirements in relation to the host plant and to the Dutch elm disease, are described for the most common species (Scolytus multistriatus (Marsham), S. pygmaeus (Fabricius), S. sulcifrons Rey and Pteleobius vittatus (Fabricius)). For the other species recorded (S. scolytus (Fabricius), S. triarmatus Eggers, S. laevis Chapuis, S. kirschii Skalitzky and P. kraatzi Eichhoff) some facts about distribution and bio-ecology are given. The elm bark beetles seem to be characterized by very different affinities with the main host plant (Ulmus minor and U. glabra) and the corresponding environments. Moreover, the bark beetle species are well differentiated in their feeding preferences and consequently in the power of transmission of the disease. LG EN.

Zimmerman, G. 1984). Dutch elm disease resistant elm varieties and present state of biological control. Biologischen Bundesanstalt Fuer Land. . Und Forstwirtschaft (west German Federal Biological Institute For Agriculture And Forestry). Mitteilungen Aus Der Biologischen Bundesanstalt Fuer Land. Und Forstwirtschaft, Berlin. Dahlem, Heft 223. 44. Deutsche Pflanzenschutz. Tagung, Giessen, 8.-12. Oktober 1984 (communications From The Federal Biology Institute For Agriculture And Forestry, Berlin. Dahlem, No. 223. 44th German Plant Protection Meeting, Giessen, West Germany, Oct. 8-12, . Xxxvii+355p. Kommissionsverlag Paul Parey: Berlin, West Germany. Illus. Paper. Isbn 3-489-22300-1. 0 (0). 1984 287.