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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.
201

The ecology and evolution of seed dispersal mutualisms between nutcrackers and pines

Siepielski, Adam M. January 2007 (has links)
Thesis (Ph. D.)--University of Wyoming, 2007. / Title from PDF title page (viewed Feb. 9, 2009). Includes bibliographical references.
202

Morphological characteristics of ponderosa pine and lodgepole pine regeneration nine years after stand density reduction at three sites in central Oregon /

Michel, Alexa K. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaves 111-118). Also available on the World Wide Web.
203

Climate-growth relationships of western juniper and ponderosa pine at the pine-woodland ecotone in southern Oregon /

Knutson, Kevin C. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 43-47). Also available on the World Wide Web.
204

Determining gene flow, linkage and parental contribution in Pinus elliottii X Pinus caribaea pine hybrids

Doyle, Jacqueline Heidi 09 February 2006 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MSc (Genetics))--University of Pretoria, 2007. / Genetics / unrestricted
205

Taxonomy of some Mexican Pines

Lara, Susana Favela January 1988 (has links)
No description available.
206

Polysaccharide synthesis during tracheid differentiation in pine

Ramsden, L. M. January 1986 (has links)
No description available.
207

Dwarf Mistletoes

Olsen, Mary W., Young, Deborah 01 1900 (has links)
3 pp. / Originally published: 2003 / Dwarf mistletoes are parasitic flowering plants that grow within host plants for about two years before producing characteristic yellow to orange or green to brown leafless aerial shoots on the outside of infected host tissue. They occur only on conifers in the pine family in Arizona and are usually host specific. This article gives information about the disease cycle, the symptoms and prevention and control methods for dwarf mistletoes.
208

Comandra Blister Rust

Olsen, Mary W., Young, Deborah 05 1900 (has links)
3 pp. / Mondell pine should not be planted within a mile of Comandra populations. Infection of pine occurs through needles by spores produced on Comandra, but spores produced on pine cannot re-infect pine. This article gives information about the disease cycle, the symptoms and prevention and control methods for blister rust.
209

Variation in transpiration and its relationship with growth for Pinus ponderosa Lawson in southern Arizona.

Budelsky, Carl Albert,1936- January 1969 (has links)
The climate, water loss, arid certain aspects of growth in semiarid-site ponderosa pine were measured from 1 February 1966 to 10 March 1967 to determine the environmental relationships governing transpiration, internal water balance, and tracheid production. Water loss from branches and from entire trees was measured by means of polyethylene enclosures. Changes In internal water status of the tree were ascertained from seasonal trends in loss of water from branches and diurnal as well as seasonal changes in the radius of the bole. The elongation of branches and needles, and the production of tracheids and their size and wall thickness were related to the coincident internal water status of the tree. The branch enclosure technique was found to be a convenient method by which the water loss process could be studied. The seasonal changes in transpiration undoubtedly were influenced by the elevated temperatures that developed within the enclosure during the day. However, the elevated temperatures did not appear to adversely influence branch and needle elongation within the chamber. Warm air temperatures and low soil moisture during June and early July increased internal water stress, reduced daytime water loss, and reduced elongation of branches and needles. Fewer tracheids were produced in the upper bole. They were small and had thick walls, Moisture from rains in July replenished soil moisture and larger, thin-walled tracheids were differentiated so that the intra-anntjlar band of small, thick-walled cells became apparent. Gradual shrinkage of the upper bole in June implied that the above changes in growth were due to changes in internal water deficits. There were no marked changes in tracheid sizes and wall thickness in the lower bole during 1966. Intra-annular bands of narrow, thick-walled tracheids occurred times during the last 10 years in the upper bole in the last 50 years in the lower bole. Graphical analysis showed that midday reductions in rates of xi transpiration during periods of low soil moisture and high air temperatures occurred in spite of steepening water vapor gradients and before stomates were closed. This evidence supports the hypothesis that reductions in water loss during midday may result directly from internal water deficits. Soil moisture, air temperature, and incident radiation appeared to influence transpiration by altering the availability of water, the vapor pressure gradient, and the energy available for evaporation.
210

Regulating interactions of pine aphid colonies (Schizolachuns pineti fabr.) and host plant growth

Lewis, G. B. January 1987 (has links)
No description available.

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