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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.
21

Evaluating white spruce decline and mortality in the upper Great Lakes region /

Brewster, Sarah A. January 2009 (has links) (PDF)
Thesis (M.S.)--University of Wisconsin--Stevens Point, 2009. / Submitted in partial fulfillment of the requirements of the degree Master of Science in Natural Resources (Forestry), College of Natural Resources. Includes bibliographical references (p. 43-50).
22

The influence of male and female strobilus production on rates of self-fertilization in a clonal white spruce seed orchard /

Denti, Daniela. January 1986 (has links)
No description available.
23

Thinning of Norway spruce /

Wallentin, Cristofer, January 2007 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2007. / Includes appendix with reprints of one published paper and three manuscripts, three of which are co-authored with others. Includes bibliographical references. Issued also electronically via World Wide Web in PDF format; online version lacks appendix.
24

Long-term effects of herbicide and precommercial thinning treatments on species composition, stand structure, and net present value in spruce-fir stands in Maine: the austin pond study /

Daggett, R. Howard, January 2003 (has links)
Thesis (M.S.) in Forestry--University of Maine, 2003. / Includes vita. Includes bibliographical references (leaves 113-118).
25

Effects of fertilizers and spacing of trees on cone production in young black spruce (Picea mariana (Mill.) B.S.P.) plantations

Smith, Ronald Frank. January 1983 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 66-74).
26

Response of interior spruce to fertilization in the interior of British Columbia

Swift, Kathie January 1991 (has links)
In 1987, a research project, conducted in the interior of British Columbia, was undertaken in order to obtain preliminary fertilization response data for three interior species. In 1988, as part of this contract, 12 screening trials were established in young interior spruce stands in the north-central interior of B. C. using factorial combinations of nitrogen and "complete" mix fertilizer. Initial assessment of the unfertilized foliage obtained from the 12 installations indicated that all stands exibited low nitrogen and potentially low sulphur levels. After fertilization, the effects of the treatments were measured by needle weight response, nutrient concentration, and subsequent nutrient content response. In all 12 installations the largest needle weight response occured when the nitrogen and the "complete" mix fertilizers were combined.. In the treatments where nitrogen was applied alone, no significant change in needle size was recorded. Nutritionally, nitrogen fertilization resulted in large increases in nitrogen concentration, indicating this element was limiting. As well, nitrogen fertilization also produced large decreases in K, S, and S04-S concentrations. Nitrogen-only fertilization also caused large elevations in the N/S ratios to occur. This elevation in N/S ratios and the subsequent decreases in S and S04-S concentrations seem to indicate that nitrogen-only fertilization has a negative impact on the sulphur nutrition of interior spruce. The addition of the "complete" mix fertilizer was, in most cases, successful in returning the decreased nutrient concentration levels of K, S, and S04 and the elevated N/S ratios back to their original unfertilized status. From these results it appears that nitrogen fertilization of interior spruce should only be considered if it is accompanied by a mixture of other nutrients; the most important component being sulphur. / Forestry, Faculty of / Graduate
27

The influence of male and female strobilus production on rates of self-fertilization in a clonal white spruce seed orchard /

Denti, Daniela. January 1986 (has links)
No description available.
28

Morphological and physiological changes with age for Sitka spruce, and their development as indices of physiological age

Steele, Michael James January 1987 (has links)
No description available.
29

The ecology of the spruce shoot aphid Cinara pilicornis (Homoptera-Aphididae)

Edwards, T. L. January 1985 (has links)
No description available.
30

Some studies in forest and agricultural mycology

Corke, Antony Trafford Kernot January 1955 (has links)
The thesis is presented in two parts. PART I. A study of Cucurbitaria piceae Borthwick, a disease of the buds of the Spruce. PART II. A study of Pseudopeziza ribis Kleb. (Gloeosporiura ribis (Lib.) Mont. and Desm.), the Leaf Spot disease of the black currant. The work which forms the basis for Part I was carried out at the Department of Botany of the University of Edinburgh prior to September 1952. It was continued, under leave of absence, together with the work described in Part II, at the Department of Agriculture and Horticulture of the University of Bristol.

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