on artificial nests of Northern Bobwhites, Colinus virginianus, by mammalian mesopredators: Does ... more on artificial nests of Northern Bobwhites, Colinus virginianus, by mammalian mesopredators: Does the problem-individual paradigm fit? Canadian Field-Naturalist 120(4): 452-456. Using mark/recapture procedures, predation on artificial nests of Northern Bobwhites (Colinus virginianus) by mammalian mesopredators (Raccoons, Procyon lotor; Virginia Opossums, Didelphis virginiana; and Striped Skunks, Mephitis mephitis) was assessed in relation to the "problem-individual" paradigm. The paradigm, which is untested among mammalian mesopredators, predicts that most predation on a prey species is by a small number of individuals repeatedly involved. By examining number of captures and recaptures on artificial nests during non-nesting and nesting periods in 2000-2003, predation within and among species were gauged. Results varied by species, sampling period, and year; however, predation was by a small percentage of individuals and only within the population of Striped Skunks were individuals (2 of 49) captured on an artificial nest more than once. Raccoons, Virginia Opossums, and Striped Skunks were responsible for 10, 2, and 12% of the loss of all nests available to predators, respectively. Based on low occurrences of individuals repeatedly involved in predation on nests, the problemindividual paradigm was unsubstantiated. Although Raccoons, Virginia Opossums, and Striped Skunks (as individual predators) had only moderate impact on the population of Northern Bobwhites, they had a much greater impact collectively (preying upon 24% of all nests available). To maximize Northern Bobwhite success, the most productive management is probably best directed toward a vertebrate guild that includes mammalian, avian, and reptilian predators, and management strategies that use multiple techniques.
This study documents the effects of cultural treatments on 17-year growth of cherrybark oak (Quer... more This study documents the effects of cultural treatments on 17-year growth of cherrybark oak (Quercus pagoda Raf.) and lobiolly pine (finus faeda L.) planted on a previously farmed bottomland site in southwestern Tennessee. Yellow-poplar (Liriodendron fulipifera L.) was part of the original study, but was excluded due to very high mortality in early years. The experiment was a randomized, complete-block design located on a former soybean field prone to occasional flooding. Cultural treatments were third-year fertilization (nitrogen and phosphorus) as well as disking and mowing for weed control. Natural regeneration as a means of afforestation also was investigated. Survival after 17 years averaged 64 percent for cherrybark oak and 63 percent for loblolly pine. Mean total height was 34.0 feet for cherrybark oak and 55.0 feet for loblolly pine. The mean diameters at breast height (DBH) of cherrybark oak and loblolly pine were 4.1 and 10.2 inches, respectively. Survival, height, and DBH of both species were not significantly affected by fertilization, mowing, or disking, nor were there any significant interactions among the treatments. Natural regeneration resulted in dense stands (4,340 trees per acre) dominated by small-diameter sweetgum (Liquidambar sfyraciflua L.).
Ensuring sustainability of intensively managed woody crops requires determining soil and water qu... more Ensuring sustainability of intensively managed woody crops requires determining soil and water quality effects using a combination of field data and modeling projections. Plot-and catchrnent-scale research, models, and meta-analyses are addressing nutrient availability, site quality, and measures to increase short-rotation woody crop (SRWC) productivity and site sustainability. Plot-scale (0.5 ha) research began in 1995 in MS, AL, and TN to compare woody and agricultural crops. In 1997, the plot scale expanded to catchment-scale SRWCs plantings (20-40 ha) on International Paper lands in South Carolina. Water quality, erosion, runoff, soil quality, and nutrient cycling are being quantified with production of SRWCs. Combined literature, meta-analyses, field data, and models (NuCM and WATRCOM) are identifying mechanisms to enhance soil carbon, fertilizer and water-use efficiency, and site sustainability, while minimizing nutrient and soil losses. Data and literature analyses demonstrate that soil cover, rates and timing of nutrient application, rainfall timing and intensity, and plant growth are keys to minimizing runoff, erosion, and nutrient transport while maximizing productivity. In SC, decreases in soil water potassium and phosphorus are indicative of previous agricultural fertilization; while increased extractable aluminum reflects increasing site acidification. Modeling simulations and water level management at the SC site are demonstrating mechanisms to enhance tree growth.
4 nsw corn-Index, the Crow Position Index (CPI) was evaluated using a 41-yesr-okl, weudocked,wnd ... more 4 nsw corn-Index, the Crow Position Index (CPI) was evaluated using a 41-yesr-okl, weudocked,wnd lwdwood stand In !aodwa&em Tn. CPI wss based on retsttve crowñ rrndcmwndiraaocuqxesoedbycrownprojectionsandrelatiwheigMsofcmp~~andtheir-. comparisonr, were made emon~ CPI, the He~yi (1974) index, end a value of Direct SunligM from the Side (DSS). CorreMtions of eeoh messure of competihen with 1 and 2 year crop tree diirneter growth were used as crbria for analysis. The highest r-values were c&u&tecl using DSS followed by the He~yl inctex snd CPI respsctlvety.
Abstract Amblyomma maculatum Koch (Acari: Ixodidae) is established in western Tennessee, a region... more Abstract Amblyomma maculatum Koch (Acari: Ixodidae) is established in western Tennessee, a region with increased risk for Rocky Mountain spotted fever and ehrlichiosis. This tick transmits Rickettsia parkeri to humans, likely contributing to cases of rickettsiosis in the region. The objective was to determine pathogen associations within questing and host-collected A. maculatum, and identify ecological factors associated with pathogen infection that may increase the effectiveness of surveillance methods. Of 265 ticks tested, 60 (22.6%) were infected with R. parkeri, and 15 (5.7%) with Candidatus Rickettsia andeanae, a Rickettsia of unknown pathogenicity. Two deer-collected ticks tested positive for Ehrlichia ewingii. No ticks were positive for Anaplasma or Borrelia species. None of the ecological factors tested (collection month, collection source, sex, and habitat type) were associated with R. parkeri infection. This project developed baseline prevalence and incidence data for monitoring pathogen prevalence in A. maculatum populations, and identified an inexpensive method for distinguishing R. parkeri from Ca. R. andeanae.
Tick-borne disease surveillance and research rely on resource-effective methods for tick collecti... more Tick-borne disease surveillance and research rely on resource-effective methods for tick collection. This study compared the respective performances of several trapping methods in a mixed grassland-forest habitat in western Tennessee. To test for temporal differences in effectiveness, sites were sampled monthly (April-August 2013) using dry ice, dragging, flagging, sweep netting, carbon dioxide (CO 2) dragging and CO 2 flagging methods. To evaluate the effect of habitat on method effectiveness, four methods (dragging, CO 2 dragging, CO 2 flagging and dry ice) were compared in four habitat types (bottomland deciduous, upland deciduous, coniferous and grassland) in June 2014. In the temporal comparison, ticks were found to be most abundant in April and May, and there was a significant sampling period and method interaction, such that method effectiveness varied across sampling period. Sweep netting was significantly less effective than the other methods. In the habitat comparison, dry ice trap collections represented the most effective method in upland deciduous and coniferous habitats. Flagging using CO 2 was significantly less effective than CO 2 dragging and dragging in bottomland deciduous habitats. The success of the various collection methods did not differ significantly within grassland habitats. Overall, dry ice trapping and dragging were the most effective methods for tick collection across time and habitat.
The association of microhabitat variables and capture (¼ occurrence) of striped skunks (Mephitis ... more The association of microhabitat variables and capture (¼ occurrence) of striped skunks (Mephitis mephitis) was assessed at 3 sites in western Tennessee. Sixteen features were included in univariate and stepwise logistic regressions to investigate relationships between occurrence and habitat factors and to construct models predictive of occurrence. Accuracy of models was examined using jackknife procedures, and maps predictive of occurrence were developed through semivariance and kriging analyses. Average height of stand, hardwood snags .35 cm diameter at breast height, number of stems, distance to permanent water sources, and distance to open areas were among the habitat features most frequently found to be related to occurrence. Models derived from logistic regression predicted occurrence of the species at varying levels (56% to 75%). Overall, classification percentages appeared to be at a level useful for predicting the occurrence of M. mephitis, and mapping procedures sufficient for illustrating the association between occurrence and habitat.
Prävalenz von aviären Hämosporidien in Osttennessee und deren Beziehung zur Biologie der Wirtsvög... more Prävalenz von aviären Hämosporidien in Osttennessee und deren Beziehung zur Biologie der Wirtsvögel Hämosporidien der Gattungen Plasmodium und Haemoproteus sind bei Vögeln verbreitete Blutparasiten, welche von zweiflügeligen Insekten (Diptera) als Vektoren übertragen werden. Für ein besseres Verständnis der Beziehung zwischen einer lokalen Vogelgemeinschaft und deren Blutparasiten, einschließlich der Verteilung der Parasiten auf die Wirtsorganismen und die zugrunde liegenden ökologischen und biologischen Faktoren, welche die Prävalenz der Parasiten bei den Wirtsarten beeinflussen, analysierten wir Blutproben von 329 Individuen aus 43 Vogelarten in Osttennessee. 144 Individuen aus 25 Arten Communicated by K. C. Klasing.
Background: Toxoplasma gondii is a widespread protozoan parasite that infects humans and other an... more Background: Toxoplasma gondii is a widespread protozoan parasite that infects humans and other animals. Previous studies indicate some genotypes of T. gondii are more frequently isolated in wildlife than agricultural animals, suggesting a wild/feral animal diversity model. To determine seroprevalence and genetic diversity of T. gondii in southeastern US wildlife, we collected sera from 471 wild animals, including 453 mammals and 18 birds, between 2011 and 2014. These serum samples were assayed for T. gondii infection using the modified agglutination test (MAT). Heart or tongue tissues from 66 seropositive animals were bioassayed in mice and 19 isolates were obtained. The isolated parasites were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method employing 10 genetic markers. Results: One hundred and ninety-six of 471 samples (41.6%) had a titer ≥1:32 and were considered positive for T. gondii infection. Of 453 mammals, 195 (43%) were seropositive, whereas only one (5.6%) of 18 birds was seropositive. The seroprevalence in mammals was significantly higher than in the birds. Mammalian hosts with adequate samples size (≥ 20) comprised white-tailed deer (n = 241), feral hogs (n = 100), raccoons (n = 34) and coyotes (n = 22), with seroprevalences of 41.0%, 51.0%, 50.0% and 72.7%, respectively. Coyotes had significantly higher seroprevalence than the white-tailed deer. Genotyping revealed five distinct genotypes, including the ToxoDB PCR-RFLP genotype #5 (a.k.a type 12) for 15 isolates, genotype #3 (a.k.a. type II) for 1 isolate, and genotypes #154, #167 and #216, each for 1 isolate. The results showed moderate to high infection rates of T. gondii in white-tailed deer, feral hogs, raccoons and coyotes. Genotyping results indicated limited genetic diversity and a dominance of genotype #5, which has been reported as a major type in wildlife in North America. Conclusions: We conclude that T. gondii infection is common in game animals (white-tailed deer and feral hogs) in the southeastern US, which may pose a food safety risk to humans. Further research is necessary to understand T. gondii transmission from wildlife to farm animals and humans.
The growth of outplanted high-quality 1-0 northern red oak (Quercus rubra L.) seedlings, growth d... more The growth of outplanted high-quality 1-0 northern red oak (Quercus rubra L.) seedlings, growth differences between two categories of visually graded seedlings and herbivory by white-tail deer (Odocoileus virginianus (Boddaert)) were examined after two growing seasons. Seedlings were planted in plots receiving three overstory treatments (high grade, commercial clearcut, and two age) and an uncut control on productive sites of the East Gulf Coastal Plain in Tennessee. Sixty seedlings were outplanted within each of 12 0.8 1-ha treatment units, resulting in three replicate blocks of the four treatments. Initial height, root-collar diameter and number of first-order lateral roots were recorded for each seedling prior to planting. Seedlings were visually graded into one of two categories (premium and good) based on morphological characteristics. Planted seedlings were measured at the end of the 2002 and 2003 growing seasons. Mean seedling survivorship after two growing seasons was 94, 92, 87 and 58% (P < 0.001) for the commercial clearcut, two-age, high grade and uncut control units, respectively. Differences in seedling height growth were found between the harvested units and uncut control units along with a significant interaction between overstory treatment and site (P = 0.03). Differences in seedling height were not significant among treatments involving harvest. After two growing seasons, seedlings graded as premium had produced 9 cm more height growth on average than seedlings graded as good (P = 0.002). In addition, seedlings browsed heavily during the 2002 and 2003 growing seasons were, on average, 36 cm shorter (P < 0.001) than unbrowsed seedlings. A significant level of mortality and diminished growth in the uncut control units suggests that pre-harvest enrichment planting without manipulating the overstory may not be a viable management option. Results from this study suggest a simple visual grading of seedlings prior to planting can result in significant growth gains early in the development of the seedlings. Further, the use of larger planting stock may have the added benefit of reducing the impacts of deer herbivory.
Bole diameter responses to fertilization, crown release, and fertilization x release treatments w... more Bole diameter responses to fertilization, crown release, and fertilization x release treatments with untreated controls and treatment-by-year interactions were studied in pole-sized (approx. 43 years old) white oak (Quercus alba L.) crop trees. In the main study, fertilizer was applied by broadcast to plots at a rate of 150 lbs N and 35 lbs P20_ per acre, and crown release removed competing trees around crop trees-dominate or codominate trees selected for favorable timber characteristicsmin randomly selected plots during spring 1993. Another fertilizer application was applied during spring 1995 at the same rate and method as the first application. Bole diameter, measured at 4.5 ft above ground line (dbh); scaling diameter inside-bark (sdib) and radial increment, both variables measured at 17.3 ft above ground; form class; and stem taper were examined. Dbh, sdib, increment, and form class were measured for 4 years beginning with 1992 pretreatment data; stem taper was measured for 1995 only. Stem taper and form class did not differ significantly among treatments (Table 1). Dbh differences among treatments were not significant; however, pooled mean dbh increased significantly each year from 9.44 inches in 1992 to 10.29 inches in 1995 (2.9% compound growth rate). Sdib differences among treatments also were not significant, but pooled mean sdib increased from 7.28 inches in 1992 to 7.97 inches in 1995 (3.1% compound growth rate). At the end of the 1993 growing season, radial increments/br release (0.12 in.) and fertilization x release (0.12 in.) treatments were significantly greater than the control (0.09 in.). The fertilization x release treatment continued to significantly increase radial increment (0.14 in.) more than fertilization and control treatments (0.11 in., both treatments) in 1994. At the end of the 1995 growing season, radial increment for fertilization x release (0.16 in.) was significantly greater than release, fertilization, and control (0.12 in., 0.11 in., 0.10 in., respectively). Fertilization x release treatment provided greater cambial increment for the first 3 years on mid-rotation white oak crop trees. Should trends continue, the fertilization x release treatment will improve volume in the first log and may improve log form more than release, fertilization, and the control treatments.
Seedling herbivory by whitetail deer [Odocoileus virginianus (Boddaert)] can be a significant pro... more Seedling herbivory by whitetail deer [Odocoileus virginianus (Boddaert)] can be a significant problem where artificial regeneration is attempted. We examined the relationship between deer herbivory and morphological traits of northern red oak (Quercus rubra L.) seedlings for two growing seasons for both browsed and non-browsed seedlings. Logistic regression analyses indicate that seedling height in each dormant season was related to terminal shoot removal (TSR) through herbivory in each of the subsequent growing seasons, 2002 and 2003 (P<0.0001 and P<0.0001, respectively). Browse line was defined as the maximum height deer attempted to browse on seedling shoots and was identified as 148 cm for the 2002 growing season. Seedlings with observed TSR in both 2002 and 2003 were 36 cm (P<0.001) smaller than seedlings with observed TSR in only one or no growing seasons. The results indicate that deer browse is inversely related to seedling size. Larger seedlings would be more likely to surpass the browse line much faster, if not at the time of planting. The cost of producing taller seedlings may be higher per capita, but higher seedling survival and the reduced need for high-density plantings may help offset the higher cost per seedling.
Continuing difficulty in the successful natural regeneration of economically important oak specie... more Continuing difficulty in the successful natural regeneration of economically important oak species (Quercus spp.) on highly productive sites has led to considerable research regarding the use of artificial oak regeneration to ensure recruitment of oak as an important component of future stands. Two obstacles to the success of some oak plantings in Tennessee are herbivory by white-tailed deer (Odocoileus virginianus (Boddaert)) and competition from an invasive non-native grass, Nepalese browntop (Microstegium vimineum (Trin.) A. Camus). We examined the effects of both deer herbivory and the Nepalese browntop on the first-year growth of outplanted, high quality, locally adapted, 1-0 northern red oak (Q. rubra L.) seedlings on the Ames Plantation in Tennessee. Northern red oak seedlings were outplanted under four overstory treatments (no cut, high grade, commercial clearcut, and two age). Seedling growth, deer browse pressure (defined as browse on terminal or lateral shoots), and herbaceous biomass were monitored monthly through the 2002 growing season. Browse pressure accounted for approximately 67 percent of the variation in total seedling height growth, and exhibited a strong negative relationship with total growth (r =-0.82; slope=-0.48). Additionally, Tukey-Kramer multiple comparison tests detected seedling height differences between the no-harvest treatment as compared with the three harvest treatments. Herbivory was prevalent early in the growing season when the seedlings first flushed, then declined during the remainder of the growing season. Analysis indicated that seedlings with a height of 148 cm or greater escaped browse. Thus, with larger seedlings planted, it may be expected that many seedlings will surpass this "browse line" in the first or second growing seasons. Linear regression revealed a strong negative relationship between Nepalese browntop biomass production and mean seedling height growth (r =-0.74; slope=-0.0046). No differences in Nepalese browntop biomass production were found between treatments (P = 0.29) with first year results, but means ranged from 45 percent in the two-age treatment to 23 percent in the no cut treatment. This range may broaden with additional time and significant differences arise. These results still suggest that canopy disturbance may encourage a growth flush of this competitive species.
The effects of seed source, fertilization, disking, and mowing on the growth of sweetgum (Liquida... more The effects of seed source, fertilization, disking, and mowing on the growth of sweetgum (Liquidambar styraciflua L.), American sycamore (Platanus occidentalis L.), and green ash (Fraxinus pennsylvanica Marsh.) were examined 18 yr after planting to determine the best system for afforestation of a previously farmed bottomland site in southwest Tennessee. Natural regeneration on the site as well as variations in soil bulk density and soil series were analyzed. Overall survival was significantly higher for sweetgum (93%) and green ash (95%) than for sycamore (88%). Height growth of sweetgum was significantly greater than that of sycamore, which was significantly greater than that of green ash. Sycamore and sweetgum of Virginia Coastal Plain origin did not differ from those of Louisiana Gulf Coast origin in growth or survival. Height and dbh of all three species were significantly increased by fertilization only on plots that were not also disked or mowed. Disking and mowing significantly increased the growth of unfertilized trees more than tkat of fertilized trees. Natural regeneration resulted in dense stands (3,445 trees/ac) dominated by sweetgum. ? he combination of fertilization and mowing significantly increased soil bulk density. Soils on the study site were more variable than previous county soil surveys indicated. South. J. Appl. For. 24(3):159-165. In the mid-1970s, falling soybean prices resulted in extensive abandonment of farmed wetlands in the Mississippi Valley (Waldrop et al. 1983). Financial models have demonstrated that planting hardwoods on sites too wet for agriculture can be profitable on better soil types (Amacher et al. 1998, Smith 1973), especially as cost-share programs, including the Conservation Reserve Program and the Wetlands Reserve Program, defray afforestation costs. In addition to harvest revenue, afforestation offers benefits of flood control, erosion prevention, and restoration of nutrients and organic matter to the site. Considerable research has focused on establishing and improving growth rates of intensively managed, short-rotation hardwood plantations (Malik et al. 1998). High-value plantations (e. g., oaks, Quercus spp.) al so have been successfully established (Ozalp et al. 1998, Russell et al. 1998, Kennedy 1993). Appropriate species-site and seed source matches are essential for successful hardwood plantations (Baker and Broadfoot 1979, Canonge 1979, Ferguson et al. 1977). Cultural treatments also improve plantation growth. Fertilization has resulted in significant growth increases in cottonwood (Populus deltoids Bartr. Ex Marsh.) (Blackmon 1977), sweetgum (Guo et al. 1998), yellow-poplar (Liriodendron tulipifera L.) (Blackmon 1974), and other hardwood species (Francis 1985). Herbaceous and woody competition control is frequently necessary to promote survival and growth of seedlings. Disking and mowing have been reported as effective and widespread methods of weed control in hardwood plantations (Krinard and Kennedy 1987, Kennedy 1984, Waldrop et al. 1983). However, few studies have reported the long-term effects of these treatments. If early growth gains are lost later in the rotation, economic returns from such treatments may be greatly diminished. The objective of this study was to determine the best system for afforestation of a previously farmed bottomland site in southwest Tennessee. The study, established in 1980, documents the 18 yr effects of seed source, fertilization, disking, and mowing on the growth of three planted hardwood species. Natural regeneration as a means of afforestation also was investigated. Soil survey analyses were conducted to examine variations in soil series and soil bulk density.
Temporal partitioning in foraging patterns of syntopic Virginia opossums (Didelphis virginiana) a... more Temporal partitioning in foraging patterns of syntopic Virginia opossums (Didelphis virginiana) and raccoons (Procyon lotor) was investigated at 3 sites in western Tennessee through the use of timers attached to live traps on trapping grids and through time-stamped remote photography using infrared-triggered cameras at bait stations. Data were analyzed using Watson's U 2-test, chi-square analyses, and probability tests. Results revealed no intraspecific differences in time of foraging for either species and a lack of interspecific differentiation. A high degree of overlap in foraging times of the species was observed. Virginia opossums and raccoons apparently did not partition their times of foraging. Foraging patterns of each species seem to be independent of the other (neutral association).
The conversion of agricultural lands to bioenergy crops show the potential for increasing long-te... more The conversion of agricultural lands to bioenergy crops show the potential for increasing long-term soil carbon sequestration and improved soil quality.
on artificial nests of Northern Bobwhites, Colinus virginianus, by mammalian mesopredators: Does ... more on artificial nests of Northern Bobwhites, Colinus virginianus, by mammalian mesopredators: Does the problem-individual paradigm fit? Canadian Field-Naturalist 120(4): 452-456. Using mark/recapture procedures, predation on artificial nests of Northern Bobwhites (Colinus virginianus) by mammalian mesopredators (Raccoons, Procyon lotor; Virginia Opossums, Didelphis virginiana; and Striped Skunks, Mephitis mephitis) was assessed in relation to the "problem-individual" paradigm. The paradigm, which is untested among mammalian mesopredators, predicts that most predation on a prey species is by a small number of individuals repeatedly involved. By examining number of captures and recaptures on artificial nests during non-nesting and nesting periods in 2000-2003, predation within and among species were gauged. Results varied by species, sampling period, and year; however, predation was by a small percentage of individuals and only within the population of Striped Skunks were individuals (2 of 49) captured on an artificial nest more than once. Raccoons, Virginia Opossums, and Striped Skunks were responsible for 10, 2, and 12% of the loss of all nests available to predators, respectively. Based on low occurrences of individuals repeatedly involved in predation on nests, the problemindividual paradigm was unsubstantiated. Although Raccoons, Virginia Opossums, and Striped Skunks (as individual predators) had only moderate impact on the population of Northern Bobwhites, they had a much greater impact collectively (preying upon 24% of all nests available). To maximize Northern Bobwhite success, the most productive management is probably best directed toward a vertebrate guild that includes mammalian, avian, and reptilian predators, and management strategies that use multiple techniques.
This study documents the effects of cultural treatments on 17-year growth of cherrybark oak (Quer... more This study documents the effects of cultural treatments on 17-year growth of cherrybark oak (Quercus pagoda Raf.) and lobiolly pine (finus faeda L.) planted on a previously farmed bottomland site in southwestern Tennessee. Yellow-poplar (Liriodendron fulipifera L.) was part of the original study, but was excluded due to very high mortality in early years. The experiment was a randomized, complete-block design located on a former soybean field prone to occasional flooding. Cultural treatments were third-year fertilization (nitrogen and phosphorus) as well as disking and mowing for weed control. Natural regeneration as a means of afforestation also was investigated. Survival after 17 years averaged 64 percent for cherrybark oak and 63 percent for loblolly pine. Mean total height was 34.0 feet for cherrybark oak and 55.0 feet for loblolly pine. The mean diameters at breast height (DBH) of cherrybark oak and loblolly pine were 4.1 and 10.2 inches, respectively. Survival, height, and DBH of both species were not significantly affected by fertilization, mowing, or disking, nor were there any significant interactions among the treatments. Natural regeneration resulted in dense stands (4,340 trees per acre) dominated by small-diameter sweetgum (Liquidambar sfyraciflua L.).
Ensuring sustainability of intensively managed woody crops requires determining soil and water qu... more Ensuring sustainability of intensively managed woody crops requires determining soil and water quality effects using a combination of field data and modeling projections. Plot-and catchrnent-scale research, models, and meta-analyses are addressing nutrient availability, site quality, and measures to increase short-rotation woody crop (SRWC) productivity and site sustainability. Plot-scale (0.5 ha) research began in 1995 in MS, AL, and TN to compare woody and agricultural crops. In 1997, the plot scale expanded to catchment-scale SRWCs plantings (20-40 ha) on International Paper lands in South Carolina. Water quality, erosion, runoff, soil quality, and nutrient cycling are being quantified with production of SRWCs. Combined literature, meta-analyses, field data, and models (NuCM and WATRCOM) are identifying mechanisms to enhance soil carbon, fertilizer and water-use efficiency, and site sustainability, while minimizing nutrient and soil losses. Data and literature analyses demonstrate that soil cover, rates and timing of nutrient application, rainfall timing and intensity, and plant growth are keys to minimizing runoff, erosion, and nutrient transport while maximizing productivity. In SC, decreases in soil water potassium and phosphorus are indicative of previous agricultural fertilization; while increased extractable aluminum reflects increasing site acidification. Modeling simulations and water level management at the SC site are demonstrating mechanisms to enhance tree growth.
4 nsw corn-Index, the Crow Position Index (CPI) was evaluated using a 41-yesr-okl, weudocked,wnd ... more 4 nsw corn-Index, the Crow Position Index (CPI) was evaluated using a 41-yesr-okl, weudocked,wnd lwdwood stand In !aodwa&em Tn. CPI wss based on retsttve crowñ rrndcmwndiraaocuqxesoedbycrownprojectionsandrelatiwheigMsofcmp~~andtheir-. comparisonr, were made emon~ CPI, the He~yi (1974) index, end a value of Direct SunligM from the Side (DSS). CorreMtions of eeoh messure of competihen with 1 and 2 year crop tree diirneter growth were used as crbria for analysis. The highest r-values were c&u&tecl using DSS followed by the He~yl inctex snd CPI respsctlvety.
Abstract Amblyomma maculatum Koch (Acari: Ixodidae) is established in western Tennessee, a region... more Abstract Amblyomma maculatum Koch (Acari: Ixodidae) is established in western Tennessee, a region with increased risk for Rocky Mountain spotted fever and ehrlichiosis. This tick transmits Rickettsia parkeri to humans, likely contributing to cases of rickettsiosis in the region. The objective was to determine pathogen associations within questing and host-collected A. maculatum, and identify ecological factors associated with pathogen infection that may increase the effectiveness of surveillance methods. Of 265 ticks tested, 60 (22.6%) were infected with R. parkeri, and 15 (5.7%) with Candidatus Rickettsia andeanae, a Rickettsia of unknown pathogenicity. Two deer-collected ticks tested positive for Ehrlichia ewingii. No ticks were positive for Anaplasma or Borrelia species. None of the ecological factors tested (collection month, collection source, sex, and habitat type) were associated with R. parkeri infection. This project developed baseline prevalence and incidence data for monitoring pathogen prevalence in A. maculatum populations, and identified an inexpensive method for distinguishing R. parkeri from Ca. R. andeanae.
Tick-borne disease surveillance and research rely on resource-effective methods for tick collecti... more Tick-borne disease surveillance and research rely on resource-effective methods for tick collection. This study compared the respective performances of several trapping methods in a mixed grassland-forest habitat in western Tennessee. To test for temporal differences in effectiveness, sites were sampled monthly (April-August 2013) using dry ice, dragging, flagging, sweep netting, carbon dioxide (CO 2) dragging and CO 2 flagging methods. To evaluate the effect of habitat on method effectiveness, four methods (dragging, CO 2 dragging, CO 2 flagging and dry ice) were compared in four habitat types (bottomland deciduous, upland deciduous, coniferous and grassland) in June 2014. In the temporal comparison, ticks were found to be most abundant in April and May, and there was a significant sampling period and method interaction, such that method effectiveness varied across sampling period. Sweep netting was significantly less effective than the other methods. In the habitat comparison, dry ice trap collections represented the most effective method in upland deciduous and coniferous habitats. Flagging using CO 2 was significantly less effective than CO 2 dragging and dragging in bottomland deciduous habitats. The success of the various collection methods did not differ significantly within grassland habitats. Overall, dry ice trapping and dragging were the most effective methods for tick collection across time and habitat.
The association of microhabitat variables and capture (¼ occurrence) of striped skunks (Mephitis ... more The association of microhabitat variables and capture (¼ occurrence) of striped skunks (Mephitis mephitis) was assessed at 3 sites in western Tennessee. Sixteen features were included in univariate and stepwise logistic regressions to investigate relationships between occurrence and habitat factors and to construct models predictive of occurrence. Accuracy of models was examined using jackknife procedures, and maps predictive of occurrence were developed through semivariance and kriging analyses. Average height of stand, hardwood snags .35 cm diameter at breast height, number of stems, distance to permanent water sources, and distance to open areas were among the habitat features most frequently found to be related to occurrence. Models derived from logistic regression predicted occurrence of the species at varying levels (56% to 75%). Overall, classification percentages appeared to be at a level useful for predicting the occurrence of M. mephitis, and mapping procedures sufficient for illustrating the association between occurrence and habitat.
Prävalenz von aviären Hämosporidien in Osttennessee und deren Beziehung zur Biologie der Wirtsvög... more Prävalenz von aviären Hämosporidien in Osttennessee und deren Beziehung zur Biologie der Wirtsvögel Hämosporidien der Gattungen Plasmodium und Haemoproteus sind bei Vögeln verbreitete Blutparasiten, welche von zweiflügeligen Insekten (Diptera) als Vektoren übertragen werden. Für ein besseres Verständnis der Beziehung zwischen einer lokalen Vogelgemeinschaft und deren Blutparasiten, einschließlich der Verteilung der Parasiten auf die Wirtsorganismen und die zugrunde liegenden ökologischen und biologischen Faktoren, welche die Prävalenz der Parasiten bei den Wirtsarten beeinflussen, analysierten wir Blutproben von 329 Individuen aus 43 Vogelarten in Osttennessee. 144 Individuen aus 25 Arten Communicated by K. C. Klasing.
Background: Toxoplasma gondii is a widespread protozoan parasite that infects humans and other an... more Background: Toxoplasma gondii is a widespread protozoan parasite that infects humans and other animals. Previous studies indicate some genotypes of T. gondii are more frequently isolated in wildlife than agricultural animals, suggesting a wild/feral animal diversity model. To determine seroprevalence and genetic diversity of T. gondii in southeastern US wildlife, we collected sera from 471 wild animals, including 453 mammals and 18 birds, between 2011 and 2014. These serum samples were assayed for T. gondii infection using the modified agglutination test (MAT). Heart or tongue tissues from 66 seropositive animals were bioassayed in mice and 19 isolates were obtained. The isolated parasites were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method employing 10 genetic markers. Results: One hundred and ninety-six of 471 samples (41.6%) had a titer ≥1:32 and were considered positive for T. gondii infection. Of 453 mammals, 195 (43%) were seropositive, whereas only one (5.6%) of 18 birds was seropositive. The seroprevalence in mammals was significantly higher than in the birds. Mammalian hosts with adequate samples size (≥ 20) comprised white-tailed deer (n = 241), feral hogs (n = 100), raccoons (n = 34) and coyotes (n = 22), with seroprevalences of 41.0%, 51.0%, 50.0% and 72.7%, respectively. Coyotes had significantly higher seroprevalence than the white-tailed deer. Genotyping revealed five distinct genotypes, including the ToxoDB PCR-RFLP genotype #5 (a.k.a type 12) for 15 isolates, genotype #3 (a.k.a. type II) for 1 isolate, and genotypes #154, #167 and #216, each for 1 isolate. The results showed moderate to high infection rates of T. gondii in white-tailed deer, feral hogs, raccoons and coyotes. Genotyping results indicated limited genetic diversity and a dominance of genotype #5, which has been reported as a major type in wildlife in North America. Conclusions: We conclude that T. gondii infection is common in game animals (white-tailed deer and feral hogs) in the southeastern US, which may pose a food safety risk to humans. Further research is necessary to understand T. gondii transmission from wildlife to farm animals and humans.
The growth of outplanted high-quality 1-0 northern red oak (Quercus rubra L.) seedlings, growth d... more The growth of outplanted high-quality 1-0 northern red oak (Quercus rubra L.) seedlings, growth differences between two categories of visually graded seedlings and herbivory by white-tail deer (Odocoileus virginianus (Boddaert)) were examined after two growing seasons. Seedlings were planted in plots receiving three overstory treatments (high grade, commercial clearcut, and two age) and an uncut control on productive sites of the East Gulf Coastal Plain in Tennessee. Sixty seedlings were outplanted within each of 12 0.8 1-ha treatment units, resulting in three replicate blocks of the four treatments. Initial height, root-collar diameter and number of first-order lateral roots were recorded for each seedling prior to planting. Seedlings were visually graded into one of two categories (premium and good) based on morphological characteristics. Planted seedlings were measured at the end of the 2002 and 2003 growing seasons. Mean seedling survivorship after two growing seasons was 94, 92, 87 and 58% (P < 0.001) for the commercial clearcut, two-age, high grade and uncut control units, respectively. Differences in seedling height growth were found between the harvested units and uncut control units along with a significant interaction between overstory treatment and site (P = 0.03). Differences in seedling height were not significant among treatments involving harvest. After two growing seasons, seedlings graded as premium had produced 9 cm more height growth on average than seedlings graded as good (P = 0.002). In addition, seedlings browsed heavily during the 2002 and 2003 growing seasons were, on average, 36 cm shorter (P < 0.001) than unbrowsed seedlings. A significant level of mortality and diminished growth in the uncut control units suggests that pre-harvest enrichment planting without manipulating the overstory may not be a viable management option. Results from this study suggest a simple visual grading of seedlings prior to planting can result in significant growth gains early in the development of the seedlings. Further, the use of larger planting stock may have the added benefit of reducing the impacts of deer herbivory.
Bole diameter responses to fertilization, crown release, and fertilization x release treatments w... more Bole diameter responses to fertilization, crown release, and fertilization x release treatments with untreated controls and treatment-by-year interactions were studied in pole-sized (approx. 43 years old) white oak (Quercus alba L.) crop trees. In the main study, fertilizer was applied by broadcast to plots at a rate of 150 lbs N and 35 lbs P20_ per acre, and crown release removed competing trees around crop trees-dominate or codominate trees selected for favorable timber characteristicsmin randomly selected plots during spring 1993. Another fertilizer application was applied during spring 1995 at the same rate and method as the first application. Bole diameter, measured at 4.5 ft above ground line (dbh); scaling diameter inside-bark (sdib) and radial increment, both variables measured at 17.3 ft above ground; form class; and stem taper were examined. Dbh, sdib, increment, and form class were measured for 4 years beginning with 1992 pretreatment data; stem taper was measured for 1995 only. Stem taper and form class did not differ significantly among treatments (Table 1). Dbh differences among treatments were not significant; however, pooled mean dbh increased significantly each year from 9.44 inches in 1992 to 10.29 inches in 1995 (2.9% compound growth rate). Sdib differences among treatments also were not significant, but pooled mean sdib increased from 7.28 inches in 1992 to 7.97 inches in 1995 (3.1% compound growth rate). At the end of the 1993 growing season, radial increments/br release (0.12 in.) and fertilization x release (0.12 in.) treatments were significantly greater than the control (0.09 in.). The fertilization x release treatment continued to significantly increase radial increment (0.14 in.) more than fertilization and control treatments (0.11 in., both treatments) in 1994. At the end of the 1995 growing season, radial increment for fertilization x release (0.16 in.) was significantly greater than release, fertilization, and control (0.12 in., 0.11 in., 0.10 in., respectively). Fertilization x release treatment provided greater cambial increment for the first 3 years on mid-rotation white oak crop trees. Should trends continue, the fertilization x release treatment will improve volume in the first log and may improve log form more than release, fertilization, and the control treatments.
Seedling herbivory by whitetail deer [Odocoileus virginianus (Boddaert)] can be a significant pro... more Seedling herbivory by whitetail deer [Odocoileus virginianus (Boddaert)] can be a significant problem where artificial regeneration is attempted. We examined the relationship between deer herbivory and morphological traits of northern red oak (Quercus rubra L.) seedlings for two growing seasons for both browsed and non-browsed seedlings. Logistic regression analyses indicate that seedling height in each dormant season was related to terminal shoot removal (TSR) through herbivory in each of the subsequent growing seasons, 2002 and 2003 (P<0.0001 and P<0.0001, respectively). Browse line was defined as the maximum height deer attempted to browse on seedling shoots and was identified as 148 cm for the 2002 growing season. Seedlings with observed TSR in both 2002 and 2003 were 36 cm (P<0.001) smaller than seedlings with observed TSR in only one or no growing seasons. The results indicate that deer browse is inversely related to seedling size. Larger seedlings would be more likely to surpass the browse line much faster, if not at the time of planting. The cost of producing taller seedlings may be higher per capita, but higher seedling survival and the reduced need for high-density plantings may help offset the higher cost per seedling.
Continuing difficulty in the successful natural regeneration of economically important oak specie... more Continuing difficulty in the successful natural regeneration of economically important oak species (Quercus spp.) on highly productive sites has led to considerable research regarding the use of artificial oak regeneration to ensure recruitment of oak as an important component of future stands. Two obstacles to the success of some oak plantings in Tennessee are herbivory by white-tailed deer (Odocoileus virginianus (Boddaert)) and competition from an invasive non-native grass, Nepalese browntop (Microstegium vimineum (Trin.) A. Camus). We examined the effects of both deer herbivory and the Nepalese browntop on the first-year growth of outplanted, high quality, locally adapted, 1-0 northern red oak (Q. rubra L.) seedlings on the Ames Plantation in Tennessee. Northern red oak seedlings were outplanted under four overstory treatments (no cut, high grade, commercial clearcut, and two age). Seedling growth, deer browse pressure (defined as browse on terminal or lateral shoots), and herbaceous biomass were monitored monthly through the 2002 growing season. Browse pressure accounted for approximately 67 percent of the variation in total seedling height growth, and exhibited a strong negative relationship with total growth (r =-0.82; slope=-0.48). Additionally, Tukey-Kramer multiple comparison tests detected seedling height differences between the no-harvest treatment as compared with the three harvest treatments. Herbivory was prevalent early in the growing season when the seedlings first flushed, then declined during the remainder of the growing season. Analysis indicated that seedlings with a height of 148 cm or greater escaped browse. Thus, with larger seedlings planted, it may be expected that many seedlings will surpass this "browse line" in the first or second growing seasons. Linear regression revealed a strong negative relationship between Nepalese browntop biomass production and mean seedling height growth (r =-0.74; slope=-0.0046). No differences in Nepalese browntop biomass production were found between treatments (P = 0.29) with first year results, but means ranged from 45 percent in the two-age treatment to 23 percent in the no cut treatment. This range may broaden with additional time and significant differences arise. These results still suggest that canopy disturbance may encourage a growth flush of this competitive species.
The effects of seed source, fertilization, disking, and mowing on the growth of sweetgum (Liquida... more The effects of seed source, fertilization, disking, and mowing on the growth of sweetgum (Liquidambar styraciflua L.), American sycamore (Platanus occidentalis L.), and green ash (Fraxinus pennsylvanica Marsh.) were examined 18 yr after planting to determine the best system for afforestation of a previously farmed bottomland site in southwest Tennessee. Natural regeneration on the site as well as variations in soil bulk density and soil series were analyzed. Overall survival was significantly higher for sweetgum (93%) and green ash (95%) than for sycamore (88%). Height growth of sweetgum was significantly greater than that of sycamore, which was significantly greater than that of green ash. Sycamore and sweetgum of Virginia Coastal Plain origin did not differ from those of Louisiana Gulf Coast origin in growth or survival. Height and dbh of all three species were significantly increased by fertilization only on plots that were not also disked or mowed. Disking and mowing significantly increased the growth of unfertilized trees more than tkat of fertilized trees. Natural regeneration resulted in dense stands (3,445 trees/ac) dominated by sweetgum. ? he combination of fertilization and mowing significantly increased soil bulk density. Soils on the study site were more variable than previous county soil surveys indicated. South. J. Appl. For. 24(3):159-165. In the mid-1970s, falling soybean prices resulted in extensive abandonment of farmed wetlands in the Mississippi Valley (Waldrop et al. 1983). Financial models have demonstrated that planting hardwoods on sites too wet for agriculture can be profitable on better soil types (Amacher et al. 1998, Smith 1973), especially as cost-share programs, including the Conservation Reserve Program and the Wetlands Reserve Program, defray afforestation costs. In addition to harvest revenue, afforestation offers benefits of flood control, erosion prevention, and restoration of nutrients and organic matter to the site. Considerable research has focused on establishing and improving growth rates of intensively managed, short-rotation hardwood plantations (Malik et al. 1998). High-value plantations (e. g., oaks, Quercus spp.) al so have been successfully established (Ozalp et al. 1998, Russell et al. 1998, Kennedy 1993). Appropriate species-site and seed source matches are essential for successful hardwood plantations (Baker and Broadfoot 1979, Canonge 1979, Ferguson et al. 1977). Cultural treatments also improve plantation growth. Fertilization has resulted in significant growth increases in cottonwood (Populus deltoids Bartr. Ex Marsh.) (Blackmon 1977), sweetgum (Guo et al. 1998), yellow-poplar (Liriodendron tulipifera L.) (Blackmon 1974), and other hardwood species (Francis 1985). Herbaceous and woody competition control is frequently necessary to promote survival and growth of seedlings. Disking and mowing have been reported as effective and widespread methods of weed control in hardwood plantations (Krinard and Kennedy 1987, Kennedy 1984, Waldrop et al. 1983). However, few studies have reported the long-term effects of these treatments. If early growth gains are lost later in the rotation, economic returns from such treatments may be greatly diminished. The objective of this study was to determine the best system for afforestation of a previously farmed bottomland site in southwest Tennessee. The study, established in 1980, documents the 18 yr effects of seed source, fertilization, disking, and mowing on the growth of three planted hardwood species. Natural regeneration as a means of afforestation also was investigated. Soil survey analyses were conducted to examine variations in soil series and soil bulk density.
Temporal partitioning in foraging patterns of syntopic Virginia opossums (Didelphis virginiana) a... more Temporal partitioning in foraging patterns of syntopic Virginia opossums (Didelphis virginiana) and raccoons (Procyon lotor) was investigated at 3 sites in western Tennessee through the use of timers attached to live traps on trapping grids and through time-stamped remote photography using infrared-triggered cameras at bait stations. Data were analyzed using Watson's U 2-test, chi-square analyses, and probability tests. Results revealed no intraspecific differences in time of foraging for either species and a lack of interspecific differentiation. A high degree of overlap in foraging times of the species was observed. Virginia opossums and raccoons apparently did not partition their times of foraging. Foraging patterns of each species seem to be independent of the other (neutral association).
The conversion of agricultural lands to bioenergy crops show the potential for increasing long-te... more The conversion of agricultural lands to bioenergy crops show the potential for increasing long-term soil carbon sequestration and improved soil quality.
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