Life Sciences Commons^™

European Aspen With High Compared To Low Constitutive Tannin Defenses Grow Taller In Response To Anthropogenic Nitrogen Enrichment, Franziska Bandau, Benedicte Riber Albrectsen, Kathryn M. Robinson, Michael J. Gundale

Aspen Bibliography

Boreal forests receive nitrogen-(N)-enrichment via atmospheric deposition and industrial fertilization. While it is known that N-enrichment can intensify interactions with natural antagonists, it remains poorly understood how genetic variability in plant defense chemistry can affect biotic interactions and height growth in N-enriched environments. We grew replicates of five low- and high-tannin Populus tremula genotypes, respectively, under three N-treatments (ambient, 15, and 150 kg N ha−1 yr−1). We assessed shoot blight occurrence (i.e. symptoms caused by Venturia fungi) during four growing seasons, and tree height growth during the same period. Damage by Venturia spp. increased with N-addition during all years, likely …

Genetic Parameters Of Growth And Adaptive Traits In Aspen (Populus Tremuloides): Implications For Tree Breeding In A Warming World, Chen Ding, Andreas Hamann, Rong-Cai Yang, Jean S. Brouard

Aspen Bibliography

Aspen (Populus tremuloides Michx) is a widespread commercial forest tree of high economic importance in western Canada and has been subject to tree improvement efforts over the past two decades. Such improvement programs rely on accurate estimates of the genetic gain in growth traits and correlated response in adaptive traits that are important for forest health. Here, we estimated genetic parameters in 10 progeny trials containing >30,000 trees with pedigree structures based on a partial factorial mating design that includes 60 half-sibs, 100 full-sib families and 1,400 clonally replicated genotypes. Estimated narrow-sense and broad-sense heritabilities were low for height …

The Effect Of Poplar Psngs1.2 Overexpression On Growth, Secondary Cell Wall, And Fiber Characteristics In Tobacco, Tingting Lu, Lulu Liu, Minjing Wei, Yingying Liu, Zianshang Qu, Chuanping Yang, Hairong Wei, Zhigang Wei

Michigan Tech Publications

The glutamine synthetase (GS1) is a key enzyme that catalyzes the reaction of glutamate and ammonia to produce glutamine in the nitrogen (N) metabolism. Previous studies on GS1s in several plant species suggest that overexpression of GS1s can enhance N utilization, accelerate plant vegetative growth, and change wood formation. In this study, we isolated a GS1 gene, termed PsnGS1.2, from Populus simonii × Populus nigra. This gene was expressed at a higher level in roots, and relatively lower but detectable levels in xylem, leaves and phloem of P. simonii × P. nigra. The protein encoded by PsnGS1.2 is …

Short-Term Carbon Partitioning Fertilizer Responses Vary Among Two Full-Sib Loblolly Pine Clones, Jeremy P. Stovall, John R. Seiler, Thomas R. Fox

Faculty Publications

We investigated the effects of fertilizer application on the partitioning of gross primary productivity (GPP) between contrasting full-sib clones of Pinus taeda (L.). Our objective was to determine if fertilizer growth responses resulted from similar short-term changes to partitioning. A modeling approach incorporating respiratory carbon (C) fluxes, soil CO2 efflux (FS), and biomass was applied to a factorial design with two clones, fertilizer and control treatments, and four sequential monthly harvests of seedlings planted in a greenhouse. Partitioning was integrated over 121 days to above, belowground, and total net primary production (ANPP + BNPP = NPP), total belowground C flux …

Slides: Challenges For Reclamation: A Western States' Perspective, Craig Bell

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Craig Bell, Western Water States Council, Midvale, Utah

9 slides

Slides: Summary: Sources Of Stress And The Changing Context Of Natural Resources Law And Policy In The New West, William R. Travis

The Future of Natural Resources Law and Policy (Summer Conference, June 6-8)

Presenter: Dr. William R. Travis, Department of Geography, University of Colorado at Boulder

43 slides

A Link Between Hurricane-Induced Tree Sprouting, High Stem Density And Short Canopy In Tropical Dry Forest, Skip Van Bloem, Peter G. Murphy, Ariel E. Lugo

Publications

The physiognomy of Caribbean dry forest is shorter, denser and contains a greater proportion of multi-stemmed trees than other neotropical dry forests. Our previous research, conducted after Hurricane Georges in 1998, has shown that dry forest trees sprout near the base following hurricane disturbance, even if the trees have not incurred structural damage. However, for these hurricane-induced sprouts to contribute to the physiognomy of the forest, they must grow and survive. We followed sprout dynamics and stem mortality on 1,407 stems from 1998, after Hurricane Georges, until 2005. The number of surviving sprouts and the proportion of sprouting stems decreased …

Structure And Development Of Pitch Canker Infected Monterey Pine Stands At Año Nuevo, California, Douglas D. Piirto, Sauli Valkonen

Natural Resources Management and Environmental Sciences

The sustainability of indigenous Monterey pine (Pinus radiata D. Don)at Ano Nuevo stands in the central coast of California was examined. The foremost management objective in these stands is to establish and maintain stand structures that ensure a sustainable presence of the species in terms of uneven-aged management. The major threats are the proliferation of shade-tolerant tree species and the pitch canker ( Fusarium circinatum) disease. The study was based on data from 17 systematically placed sample plots, measured once, in one stand with a very high degree of variation in stand structure and species composition. The results …

Slides: City Of Arcata Community Forest, Mark André

Community-Owned Forests: Possibilities, Experiences, and Lessons Learned (June 16-19)

Presenter: Mark André, Arcata, CA, Community Forest

42 slides

Growth And Phenology Of Hybrid Aspen Clones (Populus Tremula L. X Populus Tremuloides Michx.), Qibin Yu, P.M.A. Tigerstedt, Matti Haapenen

Aspen Bibliography

Height, basal diameter, diameter at breast height, bud burst, and leaf development were recorded in a 5-year-old hybrid aspen clonal trial. The field trial consisted of four aspen hybrid clones (Populus tremula x Populus tremuloides) and one local P. tremula seedling source. Phenological traits were observed in the 3rd year. Growth patterns were recorded during the 3rd and 4th years. Phenological traits were explored in relation to hybrid vigor expressed as growth traits. Differences were observed for phenological and growth traits among hybrid clones and P. tremula. The growth period varied from 143–158 days for the four hybrid clones, and …

Toxicity Of Aspen Wood Leachate To Aquatic Life: Laboratory Studies, Barry R. Taylor, J. Stephen Goudey, N. Bruce Carmichael

Aspen Bibliography

Trembling aspen (Populus tremuloides Michx.), a common hardwood tree throughout Canada, is being harvested at increasing rates for use in paper and building materials. Piles of aspen logs have been observed to produce a dark, watery, acutely toxic leachate. A laboratory study was undertaken to elucidate the nature, strength, and persistence of aspen leachate toxicity and the chemical composition of the leachate. Leaching from aspen chips in the laboratory was rapid, with 1% mass loss in the first 24 h. Another 2 weeks of immersion was necessary to remove all remaining leachable material (3% total)> Fresh aspen leachate derived …

Research Report No. 33, Climate And Growth, Christopher C. Brown, Hershel C. Reeves, J. David Lenhart

Informal Project Reports

Growth of loblolly pine (Pinus taeda L.) plantations in East Texas is influenced by many factors - soil, genetics , insects, diseases, associated vegetation and climate - to list a few items. Insights into the role that these factors contribute to the production of wood might assist East Texas plantation managers in establishing, growing and harvesting planted trees.

Stratospheric Ozone Reduction, Solar Uv-B Radiation And Terrestrial Ecosystems, Martyn M. Caldwell, Stephan D. Flint

Green Canyon Environmental Research Area, Logan Utah

Stratospheric ozone reduction is occurring and will continue to increase in magnitude into the next century. Yet, the consequences for terrestrial ecosystems of the increased solar W-B (280-320 nm) radiation resulting from total column ozone reduction are not understood. Based on studies of higher plant response to UV-B, several possible consequences for ecosystems include decreased primary production, altered plant species composition, and altered secondary chemistry with implications for herbivory, litter decomposition and biogeochemical cycles. However, like the assessment of increased atmospheric CO2, extrapolation from studies with isolated plants to ecosystem function is very tenuous at best. Very few UV-B studies …

White Pine Weevil Response To Oak Overstory Girdling - Results From A 16-Year-Old Study, S.A. Katovich, F.S. Morse

Aspen Bibliography

No abstract provided.

Management Of Aspen In The Central Rocky Mountains: An Application Of Multiple Use Silviculture, Wayne D. Shepperd

Aspen Bibliography

No abstract provided.

Development Of An Aspen Sucker Stand Following Irrigation And Fertilization, G.W. Wyckoff, D.W. Einspahr, M.K. Benson

Aspen Bibliography

A 16-18 year-old aspen stand was harvested in 1969. Aerial biomass components were determined and soils evaluated. Treatments of fertilizer, irrigation, fertilizer + irrigation and control were applied over a seven year period following harvest. Stand measurements were taken periodically over 18 years. Fertilization produced growth increases of 45-55 percent. Height, diameter, and stems per acre were affected by treatments. Guidelines for fertilizer application were developed from leaf tissue analysis.

Silviculture And Management Of Aspen In Canada: The Western Canada Scene, S. Navratil, I.E. Bella, E.B. Peterson

Aspen Bibliography

No abstract provided.

Growth Of Nitrogen-Fertilized And Thinned Quaking Aspen (Populus Tremuloides Michx.), Donald A. Perala, P.R. Laidly

Aspen Bibliography

Crop trees of quaking aspen (Populus tremuloides Michx.) and its Eurasian equivalent, P. tremula L., grow faster after thinning.

Aspnorm: A Normal Diameter Distribution Growth And Yield Model For Aspen In The Central Rocky Mountains, H.T. Mowrer

Aspen Bibliography

Development of a normal diameter distribution growth and yield model for pure, even-aged, unthinned clones of aspen in the central Rocky Mountains is described, including testing for normality of diameter distributions, development of regression estimators for stand parameters, model validation, and model application.

Effects Of Water And Temperature In Aspen: Ecology And Management In The Western United States, J.R. Jones, Merrill R. Kaufmann, E.A. Richardson

Aspen Bibliography

No abstract provided.

Growth In Aspen: Ecology And Management In The Western United States, John R. Jones, George A. Schier

Aspen Bibliography

No abstract provided.

Rmyld Update: New Growth And Yield Relationships For Aspen, C.B. Edminster, H.T. Mowrer

Aspen Bibliography

No abstract provided.

Effects Of Chemical Weed Control And Seedling Planting Depth On Survival And Growth Of Aspen, G.L. Reighard, G. Howe, J.W. Hanover

Aspen Bibliography

No abstract provided.

Internal Filters : Prospects For Uv-Acclimation In Higher Plants, Martyn M. Caldwell, Ronald Robberecht, Stephan D. Flint

Green Canyon Environmental Research Area, Logan Utah

Wavelength-selective absorption of solar radiation within plant leaves allows penetration of visible radiation to the chloroplats, while removing much of the damaging ultraviolet-B radiation. Flavonoids are important in this wavelength-selective absorption. Induction of flavonoid synthesis by solar radiation, and specifically by UV-B radiation, is discussed as this relates to the potential acclimation of plants to enhanced solar UV-B radiation that would result from stratospheric ozone reduction.

The Utilization Of Carbohydrates In Aspen Roots Following Partial Or Complete Top Removal, R.D. Fitzgerald, J. Hoddinott

Aspen Bibliography

No abstract provided.

Response Of Suppressed Conifer Seedlings To Release From An Aspen-Pine Overstorey, A.B. Berry

Aspen Bibliography

No abstract provided.

Clone Expansion And Competition Between Quaking And Bigtooth Aspen Suckers After Clearcutting, Donald A. Perala

Aspen Bibliography

The ability of quaking and bigtooth aspens (Populus tremuloids Michx., P. grandidentata Michx.) to vegetatively regenerate dense stands of root sprouts (suckers) is well documented (Brinkman and Roe 1975). Tens of thousands of suckers per hectare are commonly produced when stands are killed by fire or removed by clearcutting.

Observations On The Ecology And Evolution Of Quaking Aspen, Populus Tremuloides, In The Colorado Front Range, Jeffry B. Mitton, Michael C. Grant

Aspen Bibliography

No abstract provided.

Metric Site Index Curves For Aspen, Birch And Conifers In The Lake States, P.R. Laidly

Aspen Bibliography

Site index is the measured or estimated height of dominant and codominant trees at age 50. It is widely used both as an indicator of potential site productivity and as the basis for silvicultural recommendations for Lake States timber species.

Height-Growth Comparisons Of Some Quaking Aspen Clones In Arizona, John R. Jones, David P. Trujillo

Aspen Bibliography

No abstract provided.