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Full-Text Articles in Life Sciences

Sea Surface Salinity Measurements In The Historical Database, Frederick M. Bingham, Stephan D. Howden, Chester J. Koblinsky Dec 2002

Sea Surface Salinity Measurements In The Historical Database, Frederick M. Bingham, Stephan D. Howden, Chester J. Koblinsky

Faculty Publications

We have examined historical distributions of sea surface salinity (SSS) observations in a data set consisting of a combination of the World Ocean Database 1998 (WOD98) and a thermosalinograph and bucket salinity database collected from volunteer observing ships. It is well known that SSS in much of the world's ocean is measured infrequently or not at all. We find that 27% of one-degree squares in the world ocean (open and coastal, excluding the Arctic Ocean) had no observations of SSS in the historical database, and 70% had 10 or fewer. Systematic sampling of SSS (more than 10,000 observations per year …


Avian Use Of Chinese Tallow Seeds In Coastal Texas (Abstract), Warren C. Conway Dec 2002

Avian Use Of Chinese Tallow Seeds In Coastal Texas (Abstract), Warren C. Conway

Faculty Publications

The Chinese tallow tree (Sapium sebiferum) (Euphorbiaceae) was introduced into coastal Texas in the late 1800s and forms monotypic woodlands once naturalized. However, few studies have examined avian use of tallow seeds during fall migration in coastal Texas. We documented use of Chinese tallow seeds and compared foraging frequency on Chinese tallow seeds among permanent, summer, and winter residents and migrants. We also tested the hypothesis that Chinese tallow seed germination was enhanced by foraging activities of yellow-rumped warblers (Dendroica coronata), the most common species observed foraging on tallow seeds. During fall migration 1995 and 1996, …


Using Gis For Forest Recreation Planning On The Longleaf Ridge Special Area Of The Angelina National Forest, East Texas, I-Kuai Hung Dec 2002

Using Gis For Forest Recreation Planning On The Longleaf Ridge Special Area Of The Angelina National Forest, East Texas, I-Kuai Hung

Faculty Publications

Longleaf Ridge Special Area (LRSA) located in the Angelina National Forest is the westernmost example of a longleaf pine savanna community. Ecologically, the area is one of the most diverse communities in Texas. Due to its size, abundant natural and historical resources, numerous outdoor recreation opportunities exist. In this study, GIS was used to develop a forest recreation concept plan on LRSA. Most of the geospatial data came from public entities. Information for demand analysis on forest recreation was obtained from the 2000 National Survey on Recreation and the Environment database. U.S. Forest Service recreation fee envelope data were analyzed …


Rotational Lift: Something Different Or More Of The Same?, Jeffrey A. Walker Phd Dec 2002

Rotational Lift: Something Different Or More Of The Same?, Jeffrey A. Walker Phd

Faculty Publications

This paper addresses the question, do the rotational forces in the hovering fruit fly Drosophila melanogaster reflect something different (the Magnus effect) or more of the same (circulatory-and-attached-vortex force)? The results of an unsteady blade-element model using empirically derived force coefficients from translating (root-oscillating) wings are compared with recent results derived from both the measured forces on a dynamically scaled Drosophila wing and the computational fluid dynamic (CFD)-modeled forces on a virtual Drosophila wing. The behavior of the forces in all three models during wing rotation supports the hypothesis that rotational lift is not a novel aerodynamic mechanism but is …


Bergmann's Rule In Ectotherms: A Test Using Freshwater Fishes, Mark C. Belk, Derek D. Houston Dec 2002

Bergmann's Rule In Ectotherms: A Test Using Freshwater Fishes, Mark C. Belk, Derek D. Houston

Faculty Publications

Understanding patterns of variation in body size within and among species is a central question in evolutionary ecology (Schlichting and Pigliucci 1998). The most well known pattern of variation in body size is Bergmann's rule (Bergmann 1847; Mayr 1956). The intraspecific version of Bergmann's rule holds that within endothermic species, body size increases with increasing latitude (or decreasing temperature; Blackburn et al. 1999; Ashton et al. 2000). In general, mammals conform to this rule (Ashton et al. 2000).


Nonadditive Genetic Effects In Animal Behavior, Lisa M. Meffert, Sara K. Hicks, Jennifer L. Regan Dec 2002

Nonadditive Genetic Effects In Animal Behavior, Lisa M. Meffert, Sara K. Hicks, Jennifer L. Regan

Faculty Publications

Heritabilities, commonly used to predict evolutionary potential, are notoriously low for behaviors. Apart from strong contributions of environmental variance in reducing heritabilities, the additive genetic components can be very low, especially when they are camouflaged by nonadditive genetic effects. We first report the heritabilities of courtship traits in founder‐flush and control populations of the housefly (Musca domestica L.). We estimated the heritability of each male and female display through the regression of the courtships involving daughters and sons (with randomly selected mates) onto the “midparental” courtship values of their parents. Overall, the average heritability was significantly higher for the …


Red-Cockaded Woodpecker, U.S. Fish & Wildlife Service, Ralph Costa Oct 2002

Red-Cockaded Woodpecker, U.S. Fish & Wildlife Service, Ralph Costa

Faculty Publications

No abstract provided.


Fluid Dynamics Of Flapping Aquatic Flight In The Bird Wrasse: Three-Dimensional Unsteady Computations With Fin Deformation, Ravi Ramamurti, William C. Sandberg, Rainald Lӧhner, Jeffrey A. Walker Phd, Mark W. Westneat Oct 2002

Fluid Dynamics Of Flapping Aquatic Flight In The Bird Wrasse: Three-Dimensional Unsteady Computations With Fin Deformation, Ravi Ramamurti, William C. Sandberg, Rainald Lӧhner, Jeffrey A. Walker Phd, Mark W. Westneat

Faculty Publications

Many fishes that swim with the paired pectoral fins use fin-stroke parameters that produce thrust force from lift in a mechanism of underwater flight. These locomotor mechanisms are of interest to behavioral biologists, biomechanics researchers and engineers. In the. present study, we performed the first three-dimensional unsteady computations of fish swimming with oscillating and deforming fins. The objective of these computations was to investigate the fluid dynamics of force production associated with the flapping aquatic flight of the bird wrasse Gomphosus varius. For this computational work, we used the geometry of the wrasse and its pectoral fin, and previously measured …


Strawberry Anthracnose: Histopathology Of Colletotrichum Acutatum And C. Fragariae, Kenneth J. Curry, Maritza Abril, Jana B. Avant, Barbara J. Smith Oct 2002

Strawberry Anthracnose: Histopathology Of Colletotrichum Acutatum And C. Fragariae, Kenneth J. Curry, Maritza Abril, Jana B. Avant, Barbara J. Smith

Faculty Publications

Ontogeny of the invasion process by Colletotrichum acutatum and C. fragariae was studied on petioles and stolons of the strawberry cultivar Chandler using light and electron microscopy. The invasion of host tissue by each fungal species was similar; however, each invasion event occurred more rapidly with C. fragariae than with C. acutatum. Following cuticular penetration via an appressorium, subsequent steps of invasion involved hyphal growth within the cuticle and within the cell walls of epidermal, subepidermal, and subtending cells. Both species of fungi began invasion with a brief biotrophic phase before entering an extended necrotrophic phase. Acervuli formed once …


The Equatorial Thermocline Outcroppin - A Seasonal Control On The Tropical Pacific Ocean-Atmosphere Instability Strength, Eli Galanti, Eli Tziperman, Matthew Harrison, Anthony Rosati, Ralf Giering, Ziv Sirkes Oct 2002

The Equatorial Thermocline Outcroppin - A Seasonal Control On The Tropical Pacific Ocean-Atmosphere Instability Strength, Eli Galanti, Eli Tziperman, Matthew Harrison, Anthony Rosati, Ralf Giering, Ziv Sirkes

Faculty Publications

One of the major factors determining the strength and extent of ENSO events is the instability state of the equatorial Pacific coupled ocean-atmosphere system and its seasonal variations. This study analyzes the coupled instability in a hybrid coupled model of the Indo-Pacific region, using the adjoint method for sensitivity studies. It is found that the seasonal changes in the ocean-atmosphere instability strength in the model used here are related to the outcropping of the thermocline in the east equatorial Pacific. From July to December, when the thermocline outcrops over a wide area in the east Pacific, there is a strong …


Isolation And Characterization Of Atriplex Hortensis And Sweet Chenopodium Quinoa Starches, K. H. Wright, K. C. Huber, Daniel J. Fairbanks, C. S. Huber Oct 2002

Isolation And Characterization Of Atriplex Hortensis And Sweet Chenopodium Quinoa Starches, K. H. Wright, K. C. Huber, Daniel J. Fairbanks, C. S. Huber

Faculty Publications

Starches from garden orach (Atriplex hortensis) and sweet quinoa (Chenopodium quinoa Willd. "Surumi") seeds were isolated, examined for compositional characteristics, and compared with bitter quinoa (Cheno-podium quinoa Willd.) starch. Garden orach and sweet quinoa seeds were similar in fat and ash contents, while garden orach seeds contained 10% more protein. Starches were isolated from seeds following a 12-hr soak in dilute alkaline solution using a series of grinding, screening, centrifugation, and washing steps. Isolated starches viewed by scanning electron microscopy yielded angular, polygonal granules 2 m in diameter. Starches displayed typical A-type crystalline packing arrangements as determined by X-ray powder …


Evolution And Dynamics Of Tropical River Plumes In The Great Barrier Reef: An Integrated Remote Sensing And In Situ Study, D.M. Burrage, M.L. Heron, J.M. Hacker, T.C. Stieglitz, C.R. Steinberg, A. Prytz Sep 2002

Evolution And Dynamics Of Tropical River Plumes In The Great Barrier Reef: An Integrated Remote Sensing And In Situ Study, D.M. Burrage, M.L. Heron, J.M. Hacker, T.C. Stieglitz, C.R. Steinberg, A. Prytz

Faculty Publications

[1] The short-lived but intense discharge of freshwater from tropical rivers into the Great Barrier Reef (GBR) Lagoon and the associated salinity reductions are a critical consideration in marine research and management of the ecologically sensitive GBR World Heritage Area. Salinity provides a unique tracer that gives clues to the origin of river-borne contaminants and allows the influences of storm-induced resuspension and river discharge on turbidity to be clearly distinguished. We describe a field investigation of the evolution and dynamics of the Herbert River plume in the central GBR. Its primary goals were to use an airborne salinity mapper and …


Inhibition Of Amyloid-Β Aggregation And Caspase-3 Activation By The Ginkgo Biloba Extract Egb761, Yuan Luo, Julie V. Smith, Vijaykumar Paramasivam, Adam Burdick, Kenneth J. Curry, Justin P. Buford, Ikhlas Khan, William J. Netzer, Huaxi Xu, Peter Butko Sep 2002

Inhibition Of Amyloid-Β Aggregation And Caspase-3 Activation By The Ginkgo Biloba Extract Egb761, Yuan Luo, Julie V. Smith, Vijaykumar Paramasivam, Adam Burdick, Kenneth J. Curry, Justin P. Buford, Ikhlas Khan, William J. Netzer, Huaxi Xu, Peter Butko

Faculty Publications

Standardized extract from the leaves of the Ginkgo biloba tree, labeled EGb761, has been used in clinical trials for its beneficial effects on brain functions, particularly in connection with age-related dementias and Alzheimer's disease (AD). Substantial experimental evidence indicates that EGb761 protects against neuronal damage from a variety of insults, but its cellular and molecular mechanisms remain unknown. Using a neuroblastoma cell line stably expressing an AD-associated double mutation, we report that EGb761 inhibits formation of amyloid-β (Aβ) fibrils, which are the diagnostic, and possibly causative, feature of AD. The decreased Aβ fibrillogenesis in the presence of EGb761 was observed …


Investigating The Mechanism Of Acoustically Activated Uptake Of Drugs From Pluronic Micelles, Ghaleb A. Husseini, Christopher M. Runyan, William G. Pitt Aug 2002

Investigating The Mechanism Of Acoustically Activated Uptake Of Drugs From Pluronic Micelles, Ghaleb A. Husseini, Christopher M. Runyan, William G. Pitt

Faculty Publications

This paper examines the mechanism of ultrasonic enhanced drug delivery from Pluronic micelles. In previous publications by our group, fluorescently labeled Pluronic was shown to penetrate HL-60 cells with and without the action of ultrasound, while drug uptake was increased with the application of ultrasound. Methods In this study, the amount of uptake of two fluorescent probes, Lysosensor Green (a pH-sensitive probe) and Cell Tracker Orange CMTMR (a pH-independent probe), was measured in HL-60 and HeLa cells. Results: The results of our experiments show that the increase in drug accumulation in the cells as a result of ultrasonication is not …


Effects Of Prescribed Burning On Vegetation And Fuel Loading In Three East Texas State Parks, S. Rideout, Brian P. Oswald Aug 2002

Effects Of Prescribed Burning On Vegetation And Fuel Loading In Three East Texas State Parks, S. Rideout, Brian P. Oswald

Faculty Publications

-This study was conducted to evaluate the initial effectiveness of prescribed burning in the ecological restoration of forests within selected parks in east Texas. Twenty-four permanent plots were installed to monitor fuel loads, overstory, sapling, seedling, shrub and herbaceous layers within bum and control units of Mission Tejas, Tyler and Village Creek state parks. Measurements were taken during the summers of 1999 and 2000. Prescribed burning was conducted between these sampling periods in early spring 2ooo. Results indicated that the current applications of prescribed burning do not significantly influence vegetation or fuels. Sustained drought, prior management practices and imposed local …


Simple, Compact Source For Low-Temperature Air Plasmas, D. P. Sheehan, J. Lawson, M. Sosa, Richard A. Long Jul 2002

Simple, Compact Source For Low-Temperature Air Plasmas, D. P. Sheehan, J. Lawson, M. Sosa, Richard A. Long

Faculty Publications

A simple, compact source of low-temperature, spatially and temporally uniform air plasma using a Telsa induction coil driver is described. The low-power ionization discharge plasma is localized (2 cm X 0.5 cm X 0.1 cm) and essentially free of arc channels. A Teflon coated rolling cylindrical electrode and dielectric coated ground plate are essential to the source’s operation and allow flat test samples to be readily exposed to the plasma. The plasma is a copious source of ozone and nitrogen oxides. Its effects on various microbes are discussed.


Comparison Of Algorithms For Estimating Ocean Primary Production From Surface Chlorophyll, Temperature, And Irradiance, Janet Campbell, David Antoine, Robert Armstrong, Kevin Arrigo, William Balch, Richard Barber, Michael Behrenfield, Robert Bidigare, James Bishop, Mary-Elena Carr, Wayne Esaias, Paul Falkowski, Nicolas Hoepffner, Richard Iverson, Dale Kiefer, Steven E. Lohrenz, John Marra, Andre Morel, John Ryan, Vladimir Vedernekov, Kirk Waters, Charles Yentsch, James Yoder Jul 2002

Comparison Of Algorithms For Estimating Ocean Primary Production From Surface Chlorophyll, Temperature, And Irradiance, Janet Campbell, David Antoine, Robert Armstrong, Kevin Arrigo, William Balch, Richard Barber, Michael Behrenfield, Robert Bidigare, James Bishop, Mary-Elena Carr, Wayne Esaias, Paul Falkowski, Nicolas Hoepffner, Richard Iverson, Dale Kiefer, Steven E. Lohrenz, John Marra, Andre Morel, John Ryan, Vladimir Vedernekov, Kirk Waters, Charles Yentsch, James Yoder

Faculty Publications

[1] Results of a single-blind round-robin comparison of satellite primary productivity algorithms are presented. The goal of the round-robin exercise was to determine the accuracy of the algorithms in predicting depth-integrated primary production from information amenable to remote sensing. Twelve algorithms, developed by 10 teams, were evaluated by comparing their ability to estimate depth-integrated daily production (IP, mg C m(-2)) at 89 stations in geographically diverse provinces. Algorithms were furnished information about the surface chlorophyll concentration, temperature, photosynthetic available radiation, latitude, longitude, and day of the year. Algorithm results were then compared with IP estimates derived from (14)C uptake measurements …


Quality Attributes Of Dried Milk Products Packaged For Long-Term Storage, Michelle A. Lloyd, J. Zou, H. Farnsworth, Oscar A. Pike Jun 2002

Quality Attributes Of Dried Milk Products Packaged For Long-Term Storage, Michelle A. Lloyd, J. Zou, H. Farnsworth, Oscar A. Pike

Faculty Publications

There is a market for dehydrated foods, such as nonfat dry milk (NFDM), that are packaged for long-term storage in case of natural disasters or other emergencies. To maintain quality and optimize shelf-life, NFDM must be properly processed from good quality milk, well-packaged (minimizing moisture, light and oxygen), and stored appropriately. Research is needed to determine the variation in quality that exists in dried milk products intended for retail sale. The objective of this research was to evaluate and compare the quality of several types of dried milk products packaged for long-term storage. Ten brands of dried milk products (5 …


Seasonal Niche Strategy Of The Bloom-Forming Dinoflagellate Heterocapsa Triquetra, R. W. Litaker, P. A. Tester, C. S. Duke, B. E. Kenney, James L. Pinckney, J. Ramus May 2002

Seasonal Niche Strategy Of The Bloom-Forming Dinoflagellate Heterocapsa Triquetra, R. W. Litaker, P. A. Tester, C. S. Duke, B. E. Kenney, James L. Pinckney, J. Ramus

Faculty Publications

Heterocapsa triquetra is one of the most common bloom-forming dinoflagellates found in estuaries and near shore regions around the world. This work examined the environmental factors associated with 3 separate wintertime H. triquetra blooms in the shallow tidally mixed Newport River estuary, North Carolina, USA. During 2 of the blooms in 1982 and 1983, the estuary was sampled from a fixed, single location every hour for 14 d. During the third study, the estuary was sampled at 9 fixed locations over its entire length each week from late December 1997 through March 1998. This time period included the formation and …


Estimating The Spatial Extent Of Bottom-Water Hypoxia And Habitat Degradation In A Shallow Estuary, Christopher P. Buzzelli, Richard A. Luettich Jr., Sean P. Powers, Charles H. Peterson, Jesse E. Mcninch, James L. Pinckney, Hans W. Paerl Apr 2002

Estimating The Spatial Extent Of Bottom-Water Hypoxia And Habitat Degradation In A Shallow Estuary, Christopher P. Buzzelli, Richard A. Luettich Jr., Sean P. Powers, Charles H. Peterson, Jesse E. Mcninch, James L. Pinckney, Hans W. Paerl

Faculty Publications

Bottom-water hypoxia (≤ 2 mg 1-1 dissolved oxygen [DO]) greatly modifies the benthic habitat of estuaries, depending upon spatial extent, duration, and frequency. Bottom-water hypoxia often develops under conditions of density stratification, which inhibits vertical mixing, and warm temperatures, which enhance biological oxygen demand. Long-term, mid-channel data from the Neuse River Estuary in North Carolina permitted evaluation of how stratification and temperature combined to affect DO concentrations at the bottom. Salinity stratification (DS) and water temperature (T) explained respectively 30 and 23% of the variance in bottom-water DO concentrations. The amount of salinity stratification required to induce bottom-water …


Introduction To Forestry Investment Analysis: Part Ii. Taxes, Inflation, And Other Issues, Thomas J. Straka, Steven H. Bullard, Mark R. Dubois Feb 2002

Introduction To Forestry Investment Analysis: Part Ii. Taxes, Inflation, And Other Issues, Thomas J. Straka, Steven H. Bullard, Mark R. Dubois

Faculty Publications

Part I of this article covered the basics of compounding and discounting. You were introduced to forestry investment analysis. However, several complications were not discussed. What about inflation, taxes, and risk? Part II addresses basic complications. It also includes more detailed forestry investment analyses.


Thin Laser Light Sheet Microscope For Microbial Oceanography, Eran Fuchs, Jules S. Jaffe, Richard A. Long, Farooq Azam Jan 2002

Thin Laser Light Sheet Microscope For Microbial Oceanography, Eran Fuchs, Jules S. Jaffe, Richard A. Long, Farooq Azam

Faculty Publications

Despite a growing need, oceanographers are limited by existing technological constrains and are unable to observe aquatic microbes in their natural setting. In order to provide a simple and easy to implement solution for such studies, a new Thin Light Sheet Microscope (TLSM) has been developed. The TLSM utilizes a well-defined sheet of laser light, which has a narrow (23 micron) axial dimension over a 1 mm x 1 mm field of view. This light sheet is positioned precisely within the depth of field of the microscope’s objective lens. The technique thus utilizes conventional microscope optics but replaces the illumination …


An Equity Paradigm For Preventing Genetic Discrimination, Anita Silvers, Michael Ashley Stein Jan 2002

An Equity Paradigm For Preventing Genetic Discrimination, Anita Silvers, Michael Ashley Stein

Faculty Publications

No abstract provided.


Seed Security For Food Security, Mutizwa Mkute, Doreen Mnyulwa, Sarah Kimakwa Jan 2002

Seed Security For Food Security, Mutizwa Mkute, Doreen Mnyulwa, Sarah Kimakwa

Faculty Publications

'Farmers' dependence on agro-companies for agricultural inputs has been growing in east and southern Africa and beyond. At the same time, local and indigenous knowledge about seed selection, saving and multiplying has been lost.

This manual for development workers outlines traditional and current methods of saving seed. It begins with some basic ground rules for working with communities. The second section gives a comprehensive guide to different ways of propagating plants and saving seed from a full range of common crops and trees. Finally, the third part offers a brief outline of the background history and the current issues and …


Forest Clearcutting And Site-Preparation On A Saline Soil In East Texas: Impacts On Water Quality, Matthew W. Mcbroom, Mingteh Chang, Alexander K. Sayok Jan 2002

Forest Clearcutting And Site-Preparation On A Saline Soil In East Texas: Impacts On Water Quality, Matthew W. Mcbroom, Mingteh Chang, Alexander K. Sayok

Faculty Publications

Three 0.02 hectare plot-watersheds were installed on a saline soil in the Davy Crockett National Forest near Apple Springs, Texas. Each plot was installed with an H-flume, FW-1 automatic water level recorder, Coshocton N-1 runoff sampler, and two storage tanks. One watershed was undisturbed forested and served a control, one was clearcut without any site-preparation, and the third was clearcut, V-blade sheared, windrowed, and vegetation regrowth was prevented for the first 2 years. A total of 274 storms were recorded during the four-year study period, 1989-1992. Average annual sediment losses for the study period were 55, 197, and 1,530 kilograms …


First-Year Survival And Growth Of Bareroot And Container Water Oak And Willow Oak Seedlings Grown At Different Levels Of Mineral Nutrition, Hans Michael Williams, Matthew Stroupe Jan 2002

First-Year Survival And Growth Of Bareroot And Container Water Oak And Willow Oak Seedlings Grown At Different Levels Of Mineral Nutrition, Hans Michael Williams, Matthew Stroupe

Faculty Publications

Bareroot and container water oak (Quercus nigra) and willow oak (Quercus phellos) seedlings were treated with 3 different levels of nitrogen (N) mineral fertilizer applied during the growing season in the nursery. Comparisons were made between species, N treatments, and stock-types for seedling morphology, first-year survival and height growth, and seedling water relations. Water oak seedlings were shorter, heavier, and more first-order lateral roots than the willow oak seedlings. The N fertilizer treatments did not have a statistically significant effect on seedling morphology. Bareroot seedlings were taller, had greater root-collar diameters, and were heavier than the container seedlings. The seedlings …


Weed Control And Seedling Performance Using Oust, Velpar, And Velpar+Oust Impregnated Diammonium Phosphate, Jimmie L. Yeiser Jan 2002

Weed Control And Seedling Performance Using Oust, Velpar, And Velpar+Oust Impregnated Diammonium Phosphate, Jimmie L. Yeiser

Faculty Publications

Technology that combines herbicide and fertilizer into one treatment thereby reducing application costs while enhancing growth is needed. Four clean and well-prepared sites in TX, MS, and AL were tested. Study objectives were to evaluate the effectiveness of diammonium phosphate (DAP) impregnated with Oust, Velpar, or Velpar+Oust for herbaceous weed control and newly planted loblolly pine (Pinus taeda L.) seedling growth. In 1999, treatments were applied early post weed-emergence to 60percent bare ground in East TX. Impregnated DAP provided about 38percent less competitor control than separate liquid and fertilizer applications at similar rates. Best seedling survival and growth resulted from …


Growth Response From Herbicide, Prescribed Fire And Fertilizer Treatments In Midrotational Loblolly Pine: First-Year Results, Mary Michelle Barnett, Sandra Rideout, Brian P. Oswald, Kenneth W. Farrish, Hans Michael Williams Jan 2002

Growth Response From Herbicide, Prescribed Fire And Fertilizer Treatments In Midrotational Loblolly Pine: First-Year Results, Mary Michelle Barnett, Sandra Rideout, Brian P. Oswald, Kenneth W. Farrish, Hans Michael Williams

Faculty Publications

This study was initiated to determine growth response resulting from the application of prescribed fire and herbicide, with and without fertilizatio.n. In. southeast Texas, herbicide, prescribed fire and fertilizer treatments were applied in m1d:rotat1onal loblolly pine plantations 1.5 years after thinning. Five replications were established at. each of two study sites located on similar soils, aspects and slopes. Half of each replication. was randomly selected and fertilized. Eight treatment plots were established 1n e~ch replication with one of each of the four treatments of control, herbicide, fire, and herb1c1de/flre randomly applied to fertilized plots and one of each of the …


Potential Allelopathic Interference By The Exotic Chinese Tallow Tree (Sapium Sebiferum) (Abstract), Warren C. Conway Jan 2002

Potential Allelopathic Interference By The Exotic Chinese Tallow Tree (Sapium Sebiferum) (Abstract), Warren C. Conway

Faculty Publications

The Chinese tallow tree (Sapium sebiferum) was introduced into the southeastern

United States in late 1800s and has rapidly naturalized throughout the region’s coastal ecosystems. Because tallow forms monotypic woodlands, we hypothesized that allelopathic interference is a mechanism by which tallow maintains and expands its presence. Laboratory experiments were performed using black willow (Salix nigra), baldcypress (Taxodium distichum) and tallow, as test species, to examine the hypothesis that aqueous tallow extracts inhibit seed germination and seedling root growth, shoot growth and mass. Extracts were prepared from tallow litter, woodland soil from under tallow trees …


A Survival Model For Unthinned Loblolly Pine Plantations That Incorporates Non-Planted Tree Competition, Site Quality, And Incidence Of Fusiform Rust, Dean W. Coble, Young-Jin Lee Jan 2002

A Survival Model For Unthinned Loblolly Pine Plantations That Incorporates Non-Planted Tree Competition, Site Quality, And Incidence Of Fusiform Rust, Dean W. Coble, Young-Jin Lee

Faculty Publications

Future biomass yields are functionally related to the number of trees surviving at a given age. A stand level survival model was developed that incorporates competition of non-planted trees, site quality, and the incidence of fusiform rust (Cronartium quercuum [Berk.] Miyabe ex Shirai f. sp. fusiforme). The model consists of a system of two equations, one of which represents the number of surviving trees infected by fusiform rust while the other represents the number of trees not infected by fusiform rust. Data from unthinned loblolly pine (Pinus taeda L.) plantations in East Texas were used to fit …