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Full-Text Articles in Life Sciences

Sfa Gardens Newsletter, Sep 1999, Sfa Gardens, Stephen F. Austin State University Sep 1999

Sfa Gardens Newsletter, Sep 1999, Sfa Gardens, Stephen F. Austin State University

SFA Gardens Newsletters

No abstract provided.


Universal Design And Nature Trails: Balancing Accessibility, Site Integrity, And The Recreation Experience, Steve Kirkindall Aug 1999

Universal Design And Nature Trails: Balancing Accessibility, Site Integrity, And The Recreation Experience, Steve Kirkindall

Electronic Theses and Dissertations

This study addressed the application of Americans With Disabilities Act (ADA) guidelines in outdoor recreation settings. The purpose was three-fold: to develop site- and user-friendly design principles for non-urban, accessible nature trails; to design and construct a trail based on those principles; and to evaluate both principles and trail by surveying trail users. The Delphi Method was employed with a national panel to assess current expert opinion regarding accessibility and trails. Fifty-nine principles were developed from combined results of panel deliberations and applied experience gained constructing a prototype trail utilizing the universal design concept. Trail users rated the importance of …


Forestland: A Good Investment April 9-10, 1999, Arthur Temple College Of Forestry And Agriculture Apr 1999

Forestland: A Good Investment April 9-10, 1999, Arthur Temple College Of Forestry And Agriculture

eBooks

No abstract provided.


Strength Properties Of Juvenile And Mature Wood Of Twelve Families Of Loblolly Pine (Pinus Taeda L.), Elizabeth Lynn Forbes Apr 1999

Strength Properties Of Juvenile And Mature Wood Of Twelve Families Of Loblolly Pine (Pinus Taeda L.), Elizabeth Lynn Forbes

Electronic Theses and Dissertations

The wood mechanical properties of progeny from twelve open-pollinated parent trees were examined. Six families were from parents which had high wood specific gravity and six were from parents which had low wood specific gravity. Thirty-two-year-old trees, that had been planted at Many, Louisiana, were sampled and juvenile and mature wood test specimens were prepared. Maximum crushing strength, modulus of rupture, modulus of elasticity and wood specific gravity were determined from compression parallel to the grain tests and static bending tests. Maximum crushing strength, modulus of rupture, modulus of elasticity, and specific gravity were found to vary significantly between family …


Sfa Gardens Newsletter, Mar 1999, Sfa Gardens, Stephen F. Austin State University Mar 1999

Sfa Gardens Newsletter, Mar 1999, Sfa Gardens, Stephen F. Austin State University

SFA Gardens Newsletters

No abstract provided.


Forval For Windows: A Computer Program For Forest Valuation And Investment Analysis, Steven H. Bullard, Thomas J. Straka, James L. Carpenter Jan 1999

Forval For Windows: A Computer Program For Forest Valuation And Investment Analysis, Steven H. Bullard, Thomas J. Straka, James L. Carpenter

Faculty Publications

FORVAL (FORest VALuation) for Windows is a computer program for cash flow analysis of forestry investments. FORVAL was written in Visual Basic and is available from the Forest and Wildlife Research Center at Mississippi State University. We designed FORVAL to be used without a manual. It is user-friendly and includes a Windows Help file. Users enter the data requested for each box on the form and then press an appropriate button to perform the desired action.


Relationships Of Selected Soil Properties And Community Species Composition In Turkey Hill Wilderness Area In East Texas, Kenneth W. Farrish, Brian P. Oswald Jan 1999

Relationships Of Selected Soil Properties And Community Species Composition In Turkey Hill Wilderness Area In East Texas, Kenneth W. Farrish, Brian P. Oswald

Faculty Publications

-Sixty-nine different stands within 15 different previously managed communities were sampled in what is now the Turkey Hill Wilderness of the Angelina National Forest. Within each stand, 0.04 ha plots were randomly located, and the height, diameter, crown class and species of each tree recorded. Soil samples were collected in two locations within each plot, and the soil type confirmed at plot center. Soil samples were analyzed for selected soil chemical and physical properties. Due to the low occurrence (less than 4 times) of some communities, only six community types were analyzed Analysis of the vegetation and soil data using …


Establishment And Growth Of Cherrybark Oak Seedlings Underplanted Beneath A Partial Overstory In A Minor Bottom Of Southwestern Arkansas: First Year Results, Emile S. Gardiner Jan 1999

Establishment And Growth Of Cherrybark Oak Seedlings Underplanted Beneath A Partial Overstory In A Minor Bottom Of Southwestern Arkansas: First Year Results, Emile S. Gardiner

Faculty Publications

-Advance regeneration is frequently inadequate to sufficiently restock the oak component of many bottomland stands, especially on productive sites with high levels of competition. We initiated a study near Beirne, AR to examine the effects of pre-plant control of Japanese honeysuckle Thunberg) and seedling quality on establishment success and vigor of oak reproduction beneath a partial canopy. Nine, 2-acre plots were delineated in the stand that was harvested a residual stocking level of 30 percent in the fall of 1996. Honeysuckle pre-plant control treatments randomly applied to the nine were an Escort application in the spring of 1997, an Escort …


Financial Analysis Of Pruning Combined With Low Density Management Of Southern Yellow Pine In East Texas: An Assessment, Jayson F. Tate, A. Gordon Holley, Leslie A. Dale, Gary D. Kronrad Jan 1999

Financial Analysis Of Pruning Combined With Low Density Management Of Southern Yellow Pine In East Texas: An Assessment, Jayson F. Tate, A. Gordon Holley, Leslie A. Dale, Gary D. Kronrad

Faculty Publications

Time study was conducted on pruning of research plots in a IZyear-old loblolly pine (Pinus taeda) plantation thinned to 58 square feet basal area (190 trees) per acre. Pruning times with labor and equipment costs were used to determine per acre and per tree pruning costs. Pruning costs were used to find values necessary to break-even on a pruning investment. Soil expectation value (SEV) calculations were used to compare profitability of management utilizing heavy thinning with pruning to traditional management regimes. Calculations were performed using a current hourly wage of $8.00, stumpage price of $400.00, per thousand board feet (MBF) …


Management Of Droughty Site: Typic Quartzipsamments, Ecological Considerations, David Kulhavy, W. G. Ross, L. Allen Smith, R. R. Cahal Jan 1999

Management Of Droughty Site: Typic Quartzipsamments, Ecological Considerations, David Kulhavy, W. G. Ross, L. Allen Smith, R. R. Cahal

Faculty Publications

Pine plantations on Typic Quartzipsamments in East Texas are difficult to establish. Forest management options following clearcutting are limited. A 12 year regeneration study of the growth and survival of loblolly, Pinus faeda, L. shortleaf, P. echinata Mill., slash, f. elliofii Engelm and longleaf pines P. pa/u&is Mill. was conducted to determine optimum tree species and treatments for reforestation. With successful regeneration also comes insects and pathogens. Impacts of the Nantucket pine tip moth, Rhyacionia frusfrana, (Comstock) and the Texas leaf-cutting ant, Affa texana, (Buckley) will be discussed in the context of droughty site management.


Four-Year Growth Results From 16 Year Old Intensively Managed Low Density Loblolly Pine Plantations, A. Gordon Holley, Leslie A. Dale, Gary D. Kronrad Jan 1999

Four-Year Growth Results From 16 Year Old Intensively Managed Low Density Loblolly Pine Plantations, A. Gordon Holley, Leslie A. Dale, Gary D. Kronrad

Faculty Publications

In 1994 eighty four permanent research plots were established in two twelve year-old loblolly pine (Pinus taeda) plantations in East Texas. Plots differed in relation to: soil-site type, density of trees per acre, fertilization treatments, and competing vegetation control. Three levels of thinning treatments reduced the basal areas to 36,60, and 84 square feet of basal area (approximately 100,200, and 300 stems, respectively) per acre. All residual trees were pruned to a height of 25 feet. Plots were re-measured in 1995, 1996, and 1998. Significant differences in diameter and height growth rates were detected in 1996 and 1998. Average diameter …


Herbicide And Fertilizer Combinations For Newly Planted Loblolly Pine Seedlings On A Flatwoods Site In Southeastern Arkansas: Year Three Results, Jimmie L. Yeiser Jan 1999

Herbicide And Fertilizer Combinations For Newly Planted Loblolly Pine Seedlings On A Flatwoods Site In Southeastern Arkansas: Year Three Results, Jimmie L. Yeiser

Faculty Publications

Herbicide and fertilizer combinations were tested for enhanced loblolly pine (Pinus taeda L.) seedling performance on a chemically prepared, flatwoods site in southeastern AR. Fertilizer treatments were selected combinations of 40,50, and 50 pounds per acre of elemental N, P, or K, respectively. Arsenal+Oust (4 ounces+2 ounces per treated acre) was applied for herbaceous weed control (HWC). One treatment of herbicide or herbicide+ fertilizer was applied per year; the same rate was used for years one (1996) and two (1997). After three growing seasons, the greatest seedling volume resulted from two treatments of HWC+NPK fertilizer. Two treatments of HWC alone …


Changes In Understory Woody Vegetation In Red-Cockaded Woodpecker (Picoides Borealis) Nesting Clusters, W. D. Hacker, W. G. Ross, David Kulhavy Jan 1999

Changes In Understory Woody Vegetation In Red-Cockaded Woodpecker (Picoides Borealis) Nesting Clusters, W. D. Hacker, W. G. Ross, David Kulhavy

Faculty Publications

Understory woody vegetation in red-cockaded woodpecker nesting clusters located in Pinus taeda (L.) and P. echinara (Mill.) dominated stands were inventoried from December 1986 through January 1987 and later in January 1995 to determine what effects court-ordered management schemes had on the composition, abundance, and diversity of these stands. There was a significant difference (Pin the composition between the first sampling period and the second with species diversity increasing and a change from a

P. (aeda/P. echinara dominated community to a P. weda/Rubus spp. understory


Seedling Survival And Natural Regeneration For A Bottomland Hardwood Planting On Sites Differing In Site Preparation, Daniel T. Johns, Brett Williams, Hans M. Williams, Matthew Stroupe Jan 1999

Seedling Survival And Natural Regeneration For A Bottomland Hardwood Planting On Sites Differing In Site Preparation, Daniel T. Johns, Brett Williams, Hans M. Williams, Matthew Stroupe

Faculty Publications

In January 1998, three tracts in Hardin County, TX, were hand-planted with seven species of 1-0 bareroot bottomland hardwood seedlings. The tracts, managed by The Nature Conservancy of Texas, were previously 20-year-old pine plantations. The tracts are located within the floodplain of Village Creek. An objective for this conversion is the restoration of a bottomland hardwood wetland in order to meet Clean Water Act requirements. A pre-harvest plant inventory was conducted for each tract. The tracts were clearcut during the Winter and Spring of 1997. Following harvest, each tract was subjected to a different site preparation technique. One tract was …


Frost Heaving Of Container Hardwood Seedlings Planted In An Abandoned Agriculitural Field In Sharkey County, Mississippi, Matthew C. Stroupe, Hans M. Williams Jan 1999

Frost Heaving Of Container Hardwood Seedlings Planted In An Abandoned Agriculitural Field In Sharkey County, Mississippi, Matthew C. Stroupe, Hans M. Williams

Faculty Publications

The use of container hardwood seedlings is an alternative to bareroot planting stock. In January 1996, 1,485 container seedlings of Nuttall oak (Quercus nuttallii Palmer), willow oak (Q. phellos L.). overcup oak (Q. lyrata Walter), and water oak (Q. nigra L.) were planted in Sharkey clay on an abandoned agricultural field situated in the Lower Mississippi River Alluvial Valley. Beginning with the passage of a cold front on January 31, daily minimum temperatures dipped as low as 6 °F. For 5 days, dally high temperatures did not climb above 32 °F. This cold period caused 33.7 …


Interaction Of Soil Moisture And Seedling Shelters On Water Relations Of Baldcypress Seedlings, Ty Swirin, Hans Williams, Bob Keeland Jan 1999

Interaction Of Soil Moisture And Seedling Shelters On Water Relations Of Baldcypress Seedlings, Ty Swirin, Hans Williams, Bob Keeland

Faculty Publications

Stomata1 conductance, transpiration, and leaf water potential were measured during the 1996 growing season on baldcypress (Taxodium disfichum (L.) Rich.) seedlings. Seedlings were hand-planted from 1-O bareroot stock in mesic and permanently Rooded soil conditions. One-half of all seedlings were fitted with 122-cm tall polyethylene tree shelters, Seedlings were planted 1 year before the initiation of plant water relation measurements. The study was located within the boundary of the Longhorn Army Ammunition Plant, Kamack, TX. The objective of the research was to study the feasibility of artificially regenerating baldcypress along the shores of Caddo Lake. Stomata1 conductance and transpiration …


What’S The Monetary Value Of Your Premerchantable Timber?, Steven H. Bullard, Tom Monaghan Jan 1999

What’S The Monetary Value Of Your Premerchantable Timber?, Steven H. Bullard, Tom Monaghan

Faculty Publications

"Premerchantable" timber is not yet merchantable-in most cases this means the trees are too small to be sold for pulpwood or other commercial products. Sometimes referred to as ''precommercial" or ''immature," timber stands with average tree diameters less than five inches occupy over 50 million acres in the South-an area roughly the size of North and South Carolina combined .


Caudal Distraction By Rat Snakes (Colubridae, Elaphe): A Novel Behavior Used When Capturing Mammalian Prey, Stephen J. Mullin Jan 1999

Caudal Distraction By Rat Snakes (Colubridae, Elaphe): A Novel Behavior Used When Capturing Mammalian Prey, Stephen J. Mullin

Faculty Publications

Caudal movement in snakes may serve either a predatory (e.g., caudal luring) or defensive (eg., rattling, aposematism) function. I describe a new behavioral pattern of tail movement in snakes. Gray rat snakes (Elaphe obsoleta spiloides) foraging on small mammals (Mus domesticus) moved their tails in an erratic, whiplike fashion after detecting their prey in the vicinity. The thrashing movement in the horizontal plane was audibly and visually obvious, resulting in displacement of leaf litter around the tail. All subjects displayed the behavior, but not in all foraging episodes. Shorter durations of caudal distraction resulted in greater …


Does Nonrandom Nest Placement Imply Nonrandom Nest Predation?: A Reply, Robert J. Cooper, R. Randy Wilson, Gary D. Zenitsky, Stephen J. Mullin, Jennifer A. Dececco, Matthew R. Marshall, Dorothy J. Wolf, Lars Y. Pomara Jan 1999

Does Nonrandom Nest Placement Imply Nonrandom Nest Predation?: A Reply, Robert J. Cooper, R. Randy Wilson, Gary D. Zenitsky, Stephen J. Mullin, Jennifer A. Dececco, Matthew R. Marshall, Dorothy J. Wolf, Lars Y. Pomara

Faculty Publications

In response to the critique by Schmidt and Whelan (Condor 101 (4): 916-920, 1999), we find that the relationship between nest success and tree selectivity is dependent upon inclusion or exclusion of particular tree species, whether or not years are pooled, and the selectivity index used. We question their use of point estimates of nest success with extremely high variances, defend our index, question the application of the Chesson (1983) index to our data, and explain the need to analyze years separately. Bottomland hardwood forest systems are extremely variable; hydroperiods alter the suitability of nesting substrates, availability of alternative food, …


Iron-Induced Oxidative Stress In Erythrocyte Membranes Of Non-Insulin-Dependent Diabetic Nigerians, Gbolahan W. Okunade, Odutayo O. Odunuge, Olufunso O. Olorunsogo Jan 1999

Iron-Induced Oxidative Stress In Erythrocyte Membranes Of Non-Insulin-Dependent Diabetic Nigerians, Gbolahan W. Okunade, Odutayo O. Odunuge, Olufunso O. Olorunsogo

Faculty Publications

The presence of higher level of endogenous free radical reaction products in the erythrocyte ghost membrane (EGM) of Non-insulin-dependent diabetes mellitus (NIDDM) subjects compared with that of normal healthy controls has been demonstrated. The EGMs of NIDDM subjects were also shown to be more susceptible to exogenously generated oxidative stress than those of normal healthy individuals. The decreased level of reactive thiol groups in the EGM of NIDDM individuals supported this observation. We propose that the presence of significant levels of non-heme iron in the EGM of NIDDM subjects is an indication of the potential for iron-catalysed production of hydroxy …


Reversal Of Sodium Arsenite Inhibition Of Rat Liver Microsomal Ca2+ Pumping Atpase By Vitamin C, Odutayo O. Odunuge, Gbolahan W. Okunade, Olufunso O. Olorunsogo Jan 1999

Reversal Of Sodium Arsenite Inhibition Of Rat Liver Microsomal Ca2+ Pumping Atpase By Vitamin C, Odutayo O. Odunuge, Gbolahan W. Okunade, Olufunso O. Olorunsogo

Faculty Publications

Sodium arsenite (NaAsO2), at 10% of its median lethal dose, was administered to rats with and without vitamin C pretreatment. Liver microsomal fraction was isolated and the activity of Ca2+-ATPase was assayed. Sodium arsenite was found to inhibit the activity of the liver microsomal Ca2+-ATPase to 50% to that of control rats. The specific activity of the enzyme in rats administered sodium arsenite with vitamin C pretreatment was not significantly different from that of control rats.