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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Nantucket pine tip moth infestations in relation to stand type /

Berisford, Charles Wayne, January 1966 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute, 1966. / Vita. Abstract. Includes bibliographical references (leaves 39-41). Also available via the Internet.
62

The biology and ecology of the jack-pine budworm in Wisconsin with special reference to insect parasites

Dixon, John Charles, January 1961 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1961. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 157-164).
63

Stress detection in loblolly pine using relative apparent temperatures /

Alger, Larry Allen, January 1979 (has links)
Thesis--Virginia Polytechnic Institute and State University. / Vita. Abstract. Includes bibliographical references (leaves 49-53). Also available via the Internet.
64

Sequential occurrence of insects on 1-, 2-, and 3-year old slash pine (Pinus elliottii Engelm. var. elliottii) in northeast Florida with emphasis on the pine webworm, (Tetralopha robustella Zeller) /

Hertel, Gerard D. January 1975 (has links)
Thesis (Ph. D.)--University of Wisconsin-Madison, 1975. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 132-136).
65

Early ontogeny of jack pine and red pine seedlings

Riding, Richard Thomas, January 1967 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1967. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
66

Some aspects of the population dynamics of the mountain pine beetle, Dendroctonus ponderosae in lodgepole pine forests of British Columbia

Peterman, Randall Martin January 1974 (has links)
Outbreaks of mountain pine beetle (Dendrcctonus ronderosae Hopk.) are common in lodgepole pine forests cf western North America. Characteristics of both the tark beetle and its host tree were compared using field replicates cf epidemic and endemic areas to test for any possible intrinsic differences between populations cf trees cr insects in these two different states. laboratory studies were conducted on beetle dispersal characteristics and cn effects of attack density and female parent size on beetle reproductive success and offspring size. Results are as follows: Trees in outbreak areas are older than in endemic regions, and trees of a given size and beetle attack density are more likely to be overcome and to permit successful beetle reproduction in epidemic than in endemic areas. However, tree spatial distributions, average attack densities and proportions of trees unsuccessfully attacked by beetles dc net differ consistently between epidemic and endemic areas. A method (in which blue-staining fungi were inoculated into trees) of measuring potential of trees tc resist mountain pine beetle was tested and found to be inadequate. Epidemic and endemic bark beetles did not differ consistently in dispersal, size, cr reproductive characteristics. However, early emerging beetles were larger than late emergers and females had a larger coefficient of variation in size than males. Field and laboratory data shew that the number of offspring emerging per parent decreases with increasing attack density. Breeding experiments further indicated that, 1) small female parents produce fewer and smaller offspring than large females, 2) small female parents produce female offspring with more strongly bimcdal size distributions than large females, and 3) high parental attack densities result in smaller offspring. Dispersal studies on the insect using chemical extracts of lodgepole pine bark showed that early emerging beetles are more likely to respond positively to tree chemicals than late emergers with the same flight history. Increasing lengths of flight increase female but not male responses to these chemicals. Evidence from a simulation model is presented tc support the hypothesis that the age at which lodgepcle pine normally becomes susceptible to mountain pine beetle attack is clcse to the age at which certain tree fitness measures are maximized. / Science, Faculty of / Zoology, Department of / Graduate
67

Bluestain fungi and insect vector interactions in Japanese black and Scots pine mortality /

Bennett, Elise M. 01 January 1986 (has links) (PDF)
No description available.
68

Structural Comparisons of Sand Pine Scrubs of East-Central Florida

Latham, Pamela J. 01 January 1985 (has links) (PDF)
No description available.
69

Influence of climate on the modern and late Holocene biogeography of ponderosa pine in the central Rockies

Norris, Jodi R. January 1900 (has links)
Thesis (Ph. D.)--University of Wyoming, 2006. / Title from PDF title page (viewed on Jan. 3, 2008). Includes bibliographical references.
70

Developing stand density thresholds to address mountain pine beetle susceptibility in eastern Washington forests /

Oneil, Elaine E. January 2006 (has links)
Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 89-98).

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