Slash Pine Forest Research Articles

Habitat and Nesting Success of Blue Jays (Cyanocitta Cristata): Importance of Scale

Abstract Nesting success of birds often is influenced by habitat features surrounding nests. However, few studies have investigated habitat influences at multiple levels and spatial scales. We examined the relationship between Blue Jay (Cyanocitta cristata) nesting success and habitat at three levels (macrohabitat, microhabitat, and nest site) and at three different scales within the microhabitat level (3.1, 0.3, and 0.07 ha circular plots surrounding nests) in central Florida. We defined successful nests as those fledging at least one offspring. An eight-fold difference in probability of nesting success existed among seven distinct macrohabitats, with Mayfield success estimates ranging from 8 to 63%. However, no difference in number of fledglings per nest existed among macrohabitats when unsuccessful nests were excluded from the analysis. Macrohabitats in which nests were more often successful had more extensive slash pine (Pinus elliottii) forest. Logistic regression analyses indicated that slash pine canopy cover was significantly related to nesting success at all three microhabitat scales, although the tree species in which a nest was placed was unimportant to nesting success. Other microhabitat and nest-site features were unrelated to nesting success. Strong circumstantial evidence indicates predation was the major cause of nest failure, but relative abundance of one potential predator, the gray squirrel (Sciurus carolinensis), was not related to nesting success in macrohabitats or slash pine canopy cover within microhabitats. In this study, logistic regression models using habitat features measured at higher levels and larger scales had better predictive power, indicating that habitat may have influenced predation at scales larger than that of a typical nest patch.

Energy exchange across a chronosequence of slash pine forests in Florida

We measured net atmospheric exchanges of energy and water vapor using eddy covariance along a chronosequence of Pinus elliottii plantations in north Florida: a recent clear-cut, a mid-rotation stand, and a 24-year-old, rotation-aged stand. Reflected energy averaged 0.26 of incoming solar radiation at the clear-cut and 0.18 at the closed-canopy stands. The sum of sensible ( S), latent (LE) and soil heat fluxes accounted for 89 and 85% of net radiation ( R net) at the clear-cut and mid-rotation age sites. Both S and LE were linearly related to R net at all sites. Seasonal differences occurred in the proportion of R net attributable to S and LE. S was a much smaller proportion of R net when the clear-cut and the mid-rotation age stands were flooded in the summer. LE was a greater proportion of R net during the summer/fall at all sites when LAI was greatest. Bowen ratios ( S/LE) were 0.34, 0.50 and 0.59 in the summer/fall and 0.71, 0.77 and 1.00 in the winter/spring at the clear-cut, mid-rotation and rotation-aged stands, respectively. Maximum rates of evapotranspiration (ET) in the summer were 0.6 mm h −1 at all sites. Mean daily rates averaged 3.3 mm per day in the summer/fall and 2.0 mm per day in the winter/spring. Although, changes in LAI and canopy structure were large, annual ET estimates were similar and averaged 959, 951 and 1110 mm per year along the chronosequence. Results suggest that energy partitioning and annual ET in these pine forests are more sensitive to environmental fluctuations than to management activities.

Carbon isotopic discrimination and control of nighttime canopy δ18O‐CO2 in a pine forest in the southeastern United States

Canopy and soil CO2 concentration and isotopic measurements were conducted in a slash pine forest during a progressive drought in the southeastern United States (1) to determine and compare variations in δ13C of foliage (δCf), soil (δCs), and ecosystem‐respired CO2 (δCr) and (2) to evaluate the usefulness of a two end‐member oxygen isotope ratio (δ18O of CO2) approach to partition nighttime ecosystem respiration into soil and plant components at different heights within the canopy. The δCf was enriched by 2.2 ± 0.3 (standard error) ‰ during the extreme drought in May relative to September when precipitation was above normal. The enrichment in δCf exceeded changes in δCr and δCs for the same time period (1.6 ± 0.5 and 1.0 ± 0.4‰, respectively). Lower variations in the 13C of soil‐respired CO2 relative to the variations of the autotrophic component can buffer changes in δCr, which integrates the 13C signature of canopy and soil respired CO2. Application of a two end‐member model to canopy δ18O‐CO2 indicated that soil CO2 contribution to nighttime CO2 buildup within the canopy decreased from 100% at the soil surface to 0% within the canopy in September. In May, during the extreme drought period, soil respiration rate was 2.7 times lower than the rate in September despite similar soil temperatures (23° in May versus 19°C in September). Soil and aboveground respiration equally contributed to the nocturnal CO2 buildup within the canopy in May. Our model was limited in that it produced an upper limit value for soil respiration and neglected respiration by woody tissue.

Economic analysis of slash pine forest carbon sequestration in the southern U. S.

Abstract The impact of a carbon subsidy and tax policy on slash pine (Pinus elliottii) plantations is investigated using a modified Hartman model. Such a policy is shown to increase the optimal rotation age, land expectation value and the supply of sequestered carbon. The supply of carbon increases at a decreasing rate with the price of carbon. The supply of sawtimber increases while the supply of pulpwood decreases. The increase in land expectation value was substantial, suggesting inclusion of carbon sequestration benefits and emission costs would benefit private forestland owners. As the value of forestland increases in response to a carbon policy, more land could be devoted to forestry as opposed to other land uses such as agriculture and urban development.

Vegetation composition and structure of southern coastal plain pine forests: an ecological comparison

Longleaf pine ( Pinus palustris) ecosystems are characterized by a diverse community of native groundcover species. Critics of plantation forestry claim that loblolly ( Pinus taeda) and slash pine ( Pinus elliottii) forests are devoid of native groundcover due to associated management practices. As a result of these practices, some believe that ecosystem functions characteristic of longleaf pine are lost under loblolly and slash pine plantation management. Our objective was to quantify and compare vegetation composition and structure of longleaf, loblolly, and slash pine forests of differing ages, management strategies, and land-use histories. Information from this study will further our understanding and lead to inferences about functional differences among pine cover types. Vegetation and environmental data were collected in 49 overstory plots across Southlands Experiment Forest in Bainbridge, GA. Nested plots, i.e. midstory, understory, and herbaceous, were replicated four times within each overstory plot. Over 400 species were identified. Herbaceous species richness was variable for all three pine cover types. Herbaceous richness for longleaf, slash, and loblolly pine averaged 15, 13, and 12 species per m 2, respectively. Longleaf pine plots had significantly more ( p < 0.029) herbaceous species and greater herbaceous cover ( p < 0.001) than loblolly or slash pine plots. Longleaf and slash pine plots were otherwise similar in species richness and stand structure, both having lower overstory density, midstory density, and midstory cover than loblolly pine plots. Multivariate analyses provided additional perspectives on vegetation patterns. Ordination and classification procedures consistently placed herbaceous plots into two groups which we refer to as longleaf pine benchmark (34 plots) and non-benchmark (15 plots). Benchmark plots typically contained numerous herbaceous species characteristic of relic longleaf pine/wiregrass communities found in the area. Conversely, non-benchmark plots contained fewer species characteristic of relic longleaf pine/wiregrass communities and more ruderal species common to highly disturbed sites. The benchmark group included 12 naturally regenerated longleaf plots and 22 loblolly, slash, and longleaf pine plantation plots encompassing a broad range of silvicultural disturbances. Non-benchmark plots included eight afforested old-field plantation plots and seven cutover plantation plots. Regardless of overstory species, all afforested old fields were low either in native species richness or in abundance. Varying degrees of this groundcover condition were also found in some cutover plantation plots that were classified as non-benchmark. Environmental variables strongly influencing vegetation patterns included agricultural history and fire frequency. Results suggest that land-use history, particularly related to agriculture, has a greater influence on groundcover composition and structure in southern pine forests than more recent forest management activities or pine cover type. Additional research is needed to identify the potential for afforested old fields to recover native herbaceous species. In the interim, high-yield plantation management should initially target old-field sites which already support reduced numbers of groundcover species. Sites which have not been farmed in the past 50–60 years should be considered for longleaf pine restoration and multiple-use objectives, since they have the greatest potential for supporting diverse native vegetation.

Spatial patterns of soil and vegetation in a 40-year-old slash pine (Pinus elliottii) forest in the Coastal Plain of South Carolina, U.S.A.

A study was conducted at the Savannah River Site in a 40-year-old slash pine (Pinus elliottii Engelm.) plantation in South Carolina to characterize the spatial patterns of soil, forest floor, and plant community variables and to investigate correlations among the variables. Spatial soil and litter samples were collected on five 0.25-ha plots. The spatial patterns of the variables were characterized by global variance, autocorrelation range, and patchiness. The cross-variable relationships were explored using Pearson's correlation tests to examine functional heterogeneity (i.e., to determine if structural heterogeneity reflected ecological processes). Variances of the variables calculated without regard to spatial position (i.e., global variance) were generally low. Average range of spatial autocorrelation was about 58 m for the forest floor variables, 11 m for soil variables, 11 m for basal area of large pines (&gt;30 cm diameter at breast height), and less than 11 m for basal area of smaller pines or other woody species. Few strong spatial correlations among the forest floor and soil variables were observed. Spatial patterns of pines and hardwoods were weakly correlated with litter quality patterns and soil nitrogen. We conclude that the sample plots were generally homogeneous and that differences in soil resource levels were probably too small to influence spatial pattern of vegetation in this 40-year-old plantation.

Spatial patterns of soil and vegetation in a 40-year-old slash pine (&lt;i&gt;Pinus elliottii&lt;/i&gt;) forest in the Coastal Plain of South Carolina, U.S.A.

A study was conducted at the Savannah River Site in a 40-year-old slash pine (Pinus elliottii Engelm.) plantation in South Carolina to characterize the spatial patterns of soil, forest floor, and plant community variables and to investigate correlations among the variables. Spatial soil and litter samples were collected on five 0.25-ha plots. The spatial patterns of the variables were characterized by global variance, autocorrelation range, and patchiness. The cross-variable relationships were explored using Pearson's correlation tests to examine functional heterogeneity (i.e., to determine if structural heterogeneity reflected ecological processes). Variances of the variables calculated without regard to spatial position (i.e., global variance) were generally low. Average range of spatial autocorrelation was about 58 m for the forest floor variables, 11 m for soil variables, 11 m for basal area of large pines (>30 cm diameter at breast height), and less than 11 m for basal area of smaller pines or other ...

SPM2: A simulation model for slash pine ( Pinus elliottii) forests

A simulation model for closed-canopy slash pine forests (SPM2) includes extensions to a previously described model. Additions to SPM2 include incorporation of major understory species, addition of site water balance components, and replacing the daily time-step decomposition and growth respiration fluxes with hourly outputs. The model extensions are intended to increase generality and to provide output that can be directly compared with eddy covariance measurements. Sensitivity analysis was performed using a Latin Hypercube sampling scheme with parameter ranges of 1–5% around the nominal values. The Latin Hypercube method divides the range of each input parameter into equal probability class intervals. This approach ensures that the entire range of each parameter will be evenly sampled and the distribution of each parameter will be better represented with fewer samples. Of the 69 parameters tested, 29 contributed 5% or more to model output variable sensitivity. Foliage mass parameters affected 16 output variables, including gas exchange quantities and tree biomass variables. Sampling parameters at the ±5% level resulted in only one additional parameter (initial soil water content) influencing output above the threshold value of 5%. Simulated annual net pine canopy assimilation was 1236 g C m −2, annual pine maintenance respiration was 523 g C m −2, and pine growth respiration was 91 g m −2. Annual understory assimilation was 14% of the pine value. SPM2 simulations of all combinations of a range of atmospheric CO 2 concentrations from pre-industrial to 750 ppm, temperature increases of 0–5°C, and precipitation changes of ±40% were used to generate response surfaces for the model. Although there was a positive annual stem increment at all combinations of conditions tested, the labile carbon pool (starch and soluble sugars) was completely depleted by the end of the simulated year under many combinations of increased temperature and reduced or normal precipitation.

Arboreal Ant Community of a Pine Forest in Northern Florida

The arboreal ant fauna of the longleaf and slash pine forests of the Apalachicola National Forest in northern Florida was studied using baits placed on trunks 1 m above ground level. Crematogaster ashmeadi Mayr was by far the most abundant ant attracted to the baits, occurring on ≈50% of all the trees. In addition to C. ashmeadi, another 10 species of ants, both ground-nesting and arboreal-nesting, were commonly captured. There was a strong relationship between the identity and abundance of species of ants on pines and the mean tree diameter, indicating that the ant fauna changed as trees grew. In young, recently regenerated stands, baits attracted mostly ground-nesting species of ants. Newly mated C. ashmeadi queens colonize the dead branches of pine saplings. As tree size increased, tree occupancy by C. ashmeadi rose to a maximum of 60% in middle-sized trees and fell to 50% in the largest trees. Parallel to these changes, the proportion of trees occupied by ground-nesting ants fell from 33% in the smallest pines to ≈15% in the largest, whereas those occupied by arboreal ants other than C. ashmeadi rose from 2 to 25%. The data suggested that C. ashmeadi is a dominant ant species with which other species do not easily coexist. Coexistence of arboreal ants increased with tree size such that the proportion of trees with <1 species increased steadily from ≈4% in the smallest pines to ≈19% in the largest. The total number of species was about the same in small, medium, and large trees, but the identity of these species changed. As in other ant communities, the assembly of the arboreal ant community in this pine forest is probably an example of the nested-subset phenomenon. That is, the occurrence of species is determined by their ability to coexist with the dominant, aggressive, large-colonied species, in this case, C. ashmeadi.

A regional carbon storage simulation for large-scale biomass plantations

Establishment of biomass fuel plantations in Florida could convert as many as 224 000 ha year −1 to intensively managed sites with rotations of 2–8 years. A simulation model for slash pine ( Pinus elliottii) forests predicts that 30–40% less carbon would be stored in north Florida forests over 24 years by planting 40 000 ha year −1 of slash pine biomass plantations with an 8-year rotation. Similar impacts on regional carbon cycles should occur wherever old-growth forests are replaced by short rotation biomass plantations.

Effects of clearcutting and site preparation on herpetofauna of a North Florida flatwoods

Drift-fence sampling for 1 year yielded information on effects of clearcutting and site-preparation intensity on flatwoods herpetofauna in northern Florida. Sampling occurred in a naturally regenerated 40-year-old slash pine forest and two adjacent 3–4-year-old clearcuts subjected to different site treatments. Four drift-fence array (16 fences) in the forest captured totals of 6266 amphibians (15 species) and 230 reptiles (21 species). From an equal number of arrays in both the minimum- and maximum-treatment clearcuts, amphibian captures totalled 592 (9 species) and 758 (11 species), respectively, and reptile captures totalled 196 (19 species) and 85 (14 species), respectively. Clearcutting and site-preparation treatments did not affect amphibian species richness, but reptile species richness was lower in the maximum-treatment clearcut, due to the absence of some arboreal lizard and snake species. Clearcutting reduced amphibian abundance tenfold by affecting reproductive success. Reptile abundance was reduced by maximum site preparation but not by minimum site preparation. Arboreal lizard populations were severely reduced by clearcutting. Herpetofaunal biomass was not affected by clearcutting and site preparation, but the biomass was apportioned differently among taxonomic groups. The minimum-treatment clearcut had higher snake biomass and lower anuran biomass than the other two sites, whereas the maximum-treatment clearcut had lower lizard biomass than the other two sites. Reptile communities in flatwoods would be favored by site-preparation practices that minimized site disturbances and maximized presence of logging debris. Responses of amphibian communities seemed to be dependent upon availability of water. Overall herpetofaunal diversity would be greatest in an area containing a mosaif of small clearcuts, cypress domes, and different-aged pine stands.

Computer simulation of long-term carbon storage patterns in Florida slash pine plantations

We developed a computer model to simulate carbon storage in managed slash pine plantations in Florida. The model is based on ecosystem level carbon dynamics and land use data structured by age class of planted trees. Based on a scenario of constant planting at the average level (1952–1979), Florida slash pine forests would store carbon at the rate of 2.81 × 10 6 t year −1. However, simulated carbon storage is sensitive to the age class distribution of the forests. There will be a 10 6 t year −1 decrease in carbon storage between 1980 and 1987, due to reduced levels of planting during the past decade. This trend is relatively independent of current planting levels.

Effects of clearcutting and site preparation on water yields from slash pine forests

Three operational-sized watersheds in poorly-drained pine flatwoods forests on sandy soils of the Lower Coastal Plain in north Florida were isolated and continuously monitored for more than 3 years. Recording flumes assessed quantity of runoff water. After 1 year of calibration monitoring, two of the watersheds were harvested, site-prepared, and planted under distinct harvest and regeneration practices. Minimum practices, imposed on one watershed, consisted of manual shortwood harvest of pinelands, roller drum chopping of harvest residues and residual understory, bedding, and planting. Maximum practices, imposed on another, consisted of tree length logging of pinelands with heavy equipment, extraction of lightwood stumps, burning and windrowing of logging residue and residual understory, harrowing, bedding, and planting. Both systems increased water yields. Following minimum practices, yield increased intermittently depending on weather. Following maximum practices the increase in water yield was quicker, larger, and more persistent over various seasons and weather conditions. In both cases water yields returned to preharvest levels or less within the year following planting.

Terrestrial Activity, Abundance and Diversity of Amphibians in Differently Managed Forest Types

Diversity indices and relative abundances were determined for amphibians inhabiting three differently managed forest types in South Carolina. Study sites were contiguous around a small lake, and included a slash pine (Pinus ellioti) forest, a loblolly pine (Pinus taeda) forest and a hardwood (predominately oak-hickory) forest. Amphibians were collected using a drift fence and pitfall trap method. Captured animals were marked so that recaptures could be removed from calculations of indices. The dates of study were 30 June-10 August 1977 and 20 June-15 August 1978. The three study sites were similar in species diversity and the evenness component for combined summer data and for the summer of 1978. The hardwood forest had a higher diversity in the summer of 1977. The hardwood forest yielded approximately 50% more individual amphibians than either pine forest during both years.

Evidence of Hurricane Influence on Barrier Island Slash Pine Forests in the Northern Gulf of Mexico

Evidence of Hurricane Influence on Barrier Island Slash Pine Forests in the Northern Gulf of Mexico

Forest Pathology: Unique Features and Prospects

Foresters tend to think of us as pathologists, pathologists think of us as foresters. Both are right-most forest pathologists are professionals in both fields. Many of the unique features of forest pathology are derived from the distinctive characteris­ tics of trees, forests, and man's attitudes toward them. Trees are the largest of all land plants. They cover a larger fraction of the earth's land area than all other crops combined. Unlike most agricultural crops, forest trees do not need man to survive. They are a genetically diverse, climax or subclimax type of vegetation. Forests predominate in most areas of the world where annual rainfall exceeds 600 mm. Most forests are complex mixtures in which the species composition, genetic diversity, spatial distri­ bution, and age-size structure of stands are conditioned primarily by natural selec­ tion and competition. Intensive management and attendant changes in all of the above variables are becoming more common. But even in the mid 1970s only a small fraction of the commercial forest land in the United States has been planted or otherwise artificially regenerated, although in the southern United States, 45% of the slash pine forests are plantations. Eighty species of trees are used commercially in our home state-North Carolina; about 1000 in the world as a whole. Forests provide many values for society in addition to crops of timber. Some forests are managed for wood-based products including such diverse substances as cellophane, rayon, turpentine, or maple sugar. Forest lands also provide water for cities and towns as well as food and habitat for birds, fish, and game. Forests grace the landscape of parks and mountains. They add to the attractiveness of residential

Fertilizer movement in a a slash pine ecosystem

The movement of N in an 11-year-old slash pine forest ecosystem was followed over two growing seasons by using N15-labeled ammonium sulphate, applied in the spring at 0, 56, and 224 kg N/ha. The initial uptake of P32, applied as concentrated superphosphate at 90 kg P/ha, and of labeled N from the highest application rate was followed in two trees for 71 days.

Effects of fire on vegetation of the southeastern United States

Introduction and Historical Background Plan of Procedure I. Forests of the longleaf-slash pine belt 1. Longleaf pine forest 2. Longleaf-scrub oak forest 3. Slash pine forest 4. "Scrub" forest II. Coastal plain and bottomland hardwood forests 5. Bottomland and Mississippi Delta hardwood forests 6. Coastal plain scrub oak forests 7. Southeastern hammocks 8. Pocosins III. Coastal plain swamp forests 9. Cypress swamps 10. Southern white cedar swamps IV. Upland forests 11. Upland mixed pine and oak forests 12. Upland red cedar-hardwood forest 13. Upland scrub oak forest 14. Upland oak-hickory forest V. Natural or artificial non-forested areas 15. Southeastern prairies 16. Southeastern coastal and swamp marshes 17. Southeastern grass-sedge bogs or "savannahs" 18. Southeastern pastures Summary Literature Cited