Shortleaf Pine Research Articles

Molecular evolution of drought tolerance and wood strength related candidate genes in loblolly pine (Pinus taeda L.)

AbstractLoblolly pine (Pinus taeda L.) is an intensely studied species that has become a model system for conifers. It is one of the most important commercial crops in the southeastern United States and grows across a vast territory. Due to exposure to this current diverse environment and the fluctuating climatic conditions of the past, it has likely accumulated substantial variation in adaptive trait and wood strength related genes. We merged a set of newly collected and previously published genomic DNA sequence data and analyzed them for departures from neutrality in 32 drought tolerance and wood strength related candidate genes using neutrality tests, such as Tajima’s D, HKA, MK and nonsynonymous to synonymous substitutions ratio (Z-test). Three other major Southern pines closely related to P. taeda (Pinus echinata Mill., P. elliottii Engelm., and P. palustris Mill.) were used as outgroups in interspecific tests. In three loci (4-coumarate: CoA ligase, putative cell-wall protein and trans-cinnamate 4-hydroxylase 2) neutrality was rejected by both intra- and interspecific tests, consistent with purifying selection. Neutrality was also rejected in several other loci (alpha-tubulin, arabinogalactan 4, arabinogalactan 6, cinnamate 4-hydroxylase 1, cinnamoyl CoA reductase, cinnamyl alcohol dehydrogenase, caffeoyl CoA O-methyltransferase 1, early response to drought 3, glycine hydroxymethyltransferase, ABI1 protein phosphatase 2C-like, putative wall-associated protein kinase, and unknown gene ug_2-498); however, these results are difficult to interpret because only one of the tests proved significant. This study contributes to the ongoing discussion about natural selection in putative adaptive genes in loblolly pine. However, unambiguous interpretation of the results often remains problematic.

Geomorphological impacts of a tornado disturbance in a subtropical forest

We studied tree uprooting associated with an EF2 tornado that touched down in portions of the Ouachita Mountains in western Arkansas in 2009. In the severe blowdown areas all trees in the mixed shortleaf pine–hardwood forest were uprooted or broken, with no relationship between tree species or size and whether uprooting or breakage occurred. There was also no significant relationship between tree species and amount of soil displaced, and only a weak relationship between tree size and rootwad size. Uprooting resulted in a mean bioturbation rate of 205m3ha−1 (about 240tha−1). Direct transfer of wind energy via tree uprooting to geomorphic work of soil displacement was about 75 to 190Jm−2. Given the infrequency of tornadoes, this energy subsidy is minor with respect to the long-term energetics of pedogenesis and landscape evolution. However, it does represent a highly significant pulse of geomorphically-significant energy relative to other mechanical processes. Tornadoes such as that of April, 2009—not atypical for the region—are disturbances causing severe, non-selective impacts within the affected area. At a broader, landscape scale, tornadoes are highly localized disturbances, and occur infrequently within any given landform element or forest stand. Only about a third of the uproots revealed root penetration of bedrock, compared to about 90% in other areas of the Ouachita Mountains. This is attributable to the thicker colluvial soils at the study site, and is consistent with the idea that root–bedrock interaction is more likely in thinner regolith covers.

Frequent fire protects shortleaf pine (Pinus echinata) from introgression by loblolly pine (P. taeda)

Across much of the globe, fire is a major disturbance agent of forest and grassland communities. The removal of fire from previously fire-maintained ecosystems, which has occurred in many areas, changes species composition, favoring later less fire tolerant species over fire-adapted ones. A recent measured increase in the rate of hybridization between the fire-adapted shortleaf pine (Pinus echinata) and less fire-adapted loblolly pine (P. taeda) suggests that introgression may be an emerging threat to shortleaf pine as a genetically distinct species. We used 25 microsatellite markers on seedlings and saplings to test how the use of frequent fire affects the survival of hybrids between the two species by contrasting species makeup and hybridity in regularly burned areas (every 2 years) to that in neighboring unburned areas, both with mixed canopies of loblolly pine, shortleaf pine, and hybrids. The results show that frequent prescribed fire selects against loblolly pine and hybrids, restoring the community to one dominated by shortleaf pine. These results are the first to indicate that frequent fire can resist introgression between two co-occurring native species and that fire exclusion as a land management policy may be having unrecognized deleterious effects on the genetic integrity of species previously isolated from one another based on fire tolerance.

Red-cockaded Woodpecker Microhabitat Characteristics and Reproductive Success in a Loblolly-Shortleaf Pine Forest

We investigated the relationship between red-cockaded woodpecker (Picoides borealis) reproductive success and microhabitat characteristics in a southeastern loblolly (Pinus taeda) and shortleaf (P. echinata) pine forest. From 1997 to 1999, we recorded reproductive success parameters of 41 red-cockaded woodpecker groups at the Bienville National Forest, Mississippi. Microhabitat characteristics were measured for each group during the nesting season. Logistic regression identified understory vegetation height and small nesting season home range size as predictors of red-cockaded woodpecker nest attempts. Linear regression models identified several variables as predictors of red-cockaded woodpecker reproductive success including group density, reduced hardwood component, small nesting season home range size, and shorter foraging distances. Red-cockaded woodpecker reproductive success was correlated with habitat and behavioral characteristics that emphasize high quality habitat. By providing high quality foraging habitat during the nesting season, red-cockaded woodpeckers can successfully reproduce within small home ranges.

Influence of gap-scale disturbance on developmental and successional pathways in Quercus-Pinus stands

Quercus-Pinus forests of the eastern USA cover millions of hectares and span a variety of ecoregions. Understanding the influence of natural disturbance on developmental and successional pathways is important for managers that wish to sustain Pinus spp. in these mixtures. Quantifying developmental and successional patterns in this forest type can help assess the need to actively manage natural processes and inform silvicultural prescriptions to achieve management goals. Little research has been conducted on natural, gap-scale disturbance processes in Quercus stands with strong components of Pinus taeda, Pinus virginiana, and Pinus echinata. We examined 60 canopy gaps in a Quercus-Pinus forest on the southern Cumberland Plateau in Alabama to document gap formation, closure, and other characteristics and to analyze the influence of localized disturbance on development and succession. The majority of gapmaker trees (56%) were Pinus individuals and 44% were hardwoods. Most gaps (58%) closed by height growth of subcanopy trees. The majority of these gap filler taxa were hardwoods: Quercus (39%), Carya (14%), Nyssa sylvatica (12%), and other hardwoods (15%), with Pinus representing 14%. The number of Pinus gapmakers and the number of gaps projected to fill by subcanopy recruitment of hardwoods indicated the forest was in the latter stages of a composition shift from Pinus to a much stronger Quercus component. Significant positive relationships existed between gap size and sapling diversity (r2=0.15, P=0.002), tree diversity (r2=0.21, P=0.0002), and total stem diversity (r2=0.29, P<0.0001) indicating a positive relationship may exist between gap size and diversity on xeric ridge tops where shade-tolerant species are less competitive. We speculated the ridge top positions contributed to the relatively high gap formation rates noted in this study. Pinus composition was found to be patchy, indicating a gap-based approach may be used to manage for Pinus recruitment in hardwood dominated systems.

Structure and Dynamics of an Old-Growth Pine-Oak Community in the Southern Appalachian Mountains, Georgia, U.S.A.

Investigando la composición y estructura de los bosques de viejo crecimiento proporciona información acerca de la variabilidad espacial y temporal de los procesos responsables de desarrollo del rodal, la sucesión y los patrones biogeográficos de los bosques. Este estudio cuantifica la estructura rodal en la reserva de bosque Marshall, un remanente de bosque de viejo crecimiento situada en el noroeste de Georgia. Establecimos parcelas de inventario forestal para cuantificar la composición de especies, la estructura rodal y la dinámica sucesional. También analizamos los patrones de crecimiento radial de los árboles para documentar la edad del rodal, el reclutamiento y la frecuencia de perturbación del dosel dentro de la reserva. El bosque era dominó por el pino de hoja corta (Pinus echinata Mill.) y el castaño de roble (Quercus montana Willd.), mientras que el arce rojo (Acer rubrum L.) y la nuez dura de mockernut (Carya tomentosa Nutt.) eran abundantes en el sotobosque. Pino de hoja corta fue la especie de árbol más antiguo en la reserva, con los mas viejos excediendo 220 años de edad. Un patrón sucesional clara desarrolló sobre del siglo 20 con el establecimiento de la nuez dura y arce después de pino y roble. El agente principal de perturbación del dosel en el siglo 20 fue tormentas de hielo, que en general resultaron en la supresión del crecimiento radial de los pinos y el aumento en el crecimiento radial de los robles. Además, los pulsos de establecimiento sotobosque coincidieron con grandes tormentas de hielo. La falta de perturbación del sotobosque como el fuego puede estar permitiendo el establecimiento de especies tolerantes a la sombra de sotobosque mientras limitar el establecimiento de pino y roble. La perturbación del dosel por causa de las tormentas de hielo puede estar acelerando el ritmo de este cambio composicional. Bajo el régimen de perturbación actual, la composición de la reserva es probable que cambie, lo que lleva a un aumento de arce rojo y nuez dura de mockernut y una disminución de las especies de pino y roble.

Historic Fire and Canopy Disturbance Dynamics in an Oak-Pine (Quercus-Pinus) Forest of the Missouri Ozarks (1624–2010)

ABSTRACT Studies of historic forest disturbances provide an important context for the ecological dynamics that affect forest structure and successional trajectory. Previous historical disturbance research in the Missouri Ozark Highlands has highlighted the dynamics of fire regimes. However, little is known concerning canopy disturbance regimes in this region. The primary objective of this study was to reconstruct the history of multiple disturbances at a site that was known for having both historic Native and Euro-American activity. We analyzed the radial growth of shortleaf pine (Pinus echinata Mill.) and white oak (Quercus alba L.) to infer growth release events and documented historic fire events based on fire-scarred P. echinata. The majority of trees (87%) exhibited at least one growth release between 1624 and 2000 with the earliest growth release occurring in 1645. A total of 39 fires were documented between 1706 and 1915. Mean duration of growth releases for both species was approximately six years...

Serendipitous Data Following a Severe Windstorm in an Old-Growth Pine Stand

Reliable dimensional data for old-growth pine-dominated forests in the Gulf Coastal Plain of Arkansas are hard to find, but sometimes unfortunate circumstances provide good opportunities to acquire this information. On July 11, 2013, a severe thunderstorm with high winds struck the Levi Wilcoxon Demonstration Forest (LWDF) near Hamburg, Arkansas. This storm uprooted or snapped dozens of large pines and hardwoods and provided an opportunity to more closely inspect these rare specimens. For instance, the largest tree killed in this event, a loblolly pine (Pinus taeda), was 105 cm in diameter at breast height, 39.3 m tall, and if the tree had been sound would have yielded 3,803 board feet (Doyle log rule) of lumber. Gross board foot volume yield was also estimated from two other recently toppled large pines, an 85-cm-DBH loblolly and an 86-cm-DBH shortleaf pine (Pinus echinata), which tallied 2,430 and 2,312 board feet Doyle, respectively. A number of the other wind thrown pines on the LWDF were sound enough to count their rings for a reasonable (± 2-5 years) estimate of their ages. The stump of the fallen national champion shortleaf pine had 168 rings, and counts from other pines toppled by this storm had from 68 to 198 rings. We also searched for a new champion shortleaf pine using a LiDAR canopy height model of the LWDF to narrow our search. This preliminary assessment produced a number of targets that exceeded 40 m in height; further field checking of the tallest of these trees found that these were loblolly pines up to about 44 m. We eventually found shortleaf pines between 37 and 41 m tall, with diameters of up to 85 cm, indicating that the LWDF could still contain the Arkansas state champion.

Assessing and comparing risk to climate changes among forested locations: implications for ecosystem services

Forests provide key ecosystem services (ES) and the extent to which the ES are realized varies spatially, with forest composition and cultural context, and in breadth, depending on the dominant tree species inhabiting an area. We address the question of how climate change may impact ES within the temperate and diverse forests of the eastern United States. We quantify the vulnerability to changes in forest habitat by 2100, based on the overall pressures of community change from an aggregation of current and potential future habitats for 134 tree species at each of 149 US Department of Defense installations. To do so, we derive an index, Forest-Related Index of Climate Vulnerability, composed of several indicators of vulnerability for each site. Further, a risk matrix (likelihood 9 consequences) provides a visual cue to compare vulnerabilities among species (example from Pennsylvania) or among sites (example for Acer saccharum (sugar maple) in Vermont vs. Kentucky). Potential changes in specific ES can then be qualita- tively examined. For example in Pennsylvania, the loss of the provisioning services (wood products) of Prunus serotina (black cherry) and Fraxinus ameri- cana (white ash) habitat projected for the future will not likely be compensated for by concomitant increases in Juniperus virginiana (redcedar) and Pinus echinata (shortleaf pine) habitat. Taken together, this approach provides a conceptual framework that allows for consideration of how potential changes in tree species habitats, as impacted by climate change, can be combined to explore relative changes in important ES that forests provide.

Measurement of various properties of Southern pine and aspen as function of heat treatment

The objective of this study was to investigate the influence of heat treatment parameters, namely temperature and exposure time on surface roughness, shear strength, hardness and density of Southern pine (Pinus echinata) and aspen (Populus grandidentata) samples. The specimens were exposed to two different temperature levels of 120–200°C for time spans of 2–8h. A stylus type portable profilometer was employed to evaluate the surface characteristics of the samples by taking measurements across the grain orientation. Average roughness (Ra), mean peak-to-valley height (Rz) and maximum roughness (Rmax) were used to evaluate surface roughness of the samples exposed to various heat treatment schedules. Comten testing unit was also used to determine shear strength and Janka hardness of the control and heat treated specimens. Based on the results of this study Southern pine samples had more enhanced surface quality but lower hardness values than those of aspen specimens with increased temperature and time of heat treatment schedules. It was found that heat treatment adversely affected hardness and shear strength properties of all types of samples. Reduction in shear strength values of Southern pine and aspen samples ranged from 23.31% to 68.59% and from 4.67% to 48.55%, respectively as compared to those of control samples. It appears that influence of heat treatment on all properties of the samples was more pronounced with increasing temperature and exposure time.

Prior Prevalence of Shortleaf Pine-Oak-Hickory Woodlands in the Tallahassee Red Hills

ABSTRACT Shortleaf pine-oak-hickory woodlands provided the principal vegetation cover in the Tallahassee Red Hills prior to land clearing for plantation agriculture in the 19th century. Ample historical documentation and extant remnants of that community, including old-growth, support this conclusion. This woodland was maintained by surface fires and consisted principally of open stands of shortleaf pine, post oak, Spanish oak, black oak, mockernut hickory, and dogwood. The species-diverse and predominantly herbaceous ground cover was dominated by grasses, legumes, and composites. Coppice sprouting of trees and shrubs after fires was common. In the absence of fire, shortleaf pine-oak-hickory woodlands convert to oak-hickory forest with similar tree species composition and loss of herbaceous species. Within the past 130 years, nearly all stands of shortleaf pine-oak-hickory woodlands and oak-hickory forests have been extirpated or compromised beyond recognition by intrusions of offsite tree species that ar...

Hybridization in Naturally Regenerated Shortleaf Pine as Affected by the Distance to Nearby Artificially Regenerated Stands of Loblolly Pine

The natural range of shortleaf pine encompasses 22 states from New York to Texas, second only to eastern white pine in the eastern United States. It is a species of minor and varying occurrence in most of these states usually found in association with other pines, but it is the only naturally occurring pine in the northwestern part of its range in Oklahoma, Arkansas, and Missouri. Over the whole of this area, it is apparent that shortleaf pine hybridizes with loblolly pine, including areas of species overlap (sympatry) and nonoverlap (allopatry). In this study, we used 25 DNA markers to measure the levels of hybridization and introgression in populations of juvenile and mature shortleaf pine from a wilderness area within the allopatric range of shortleaf pine that bordered loblolly pine plantings. Frequency of hybrids ranged from 9.2 to 24.0% among the populations sampled, and we found that levels of hybridization correlates with distances to the nearest loblolly pine plantations. However, the rates of hybridization and introgression apparently remained the same among the parent and juvenile populations.

Recovery from topkill of shortleaf pine × loblolly pine hybrids compared to their parent populations

Hybrids between shortleaf pine (Pinus echinata Mill.) and loblolly pine (Pinus taeda L.) have increased since the 1950s throughout the southeastern USA. Previously, greater sprouting capacity and the formation of a basal crook that lowers the height of dormant buds may have favored pure shortleaf pine populations on fire prone sites. The objective of this study was to determine how seasonal timing of topkill by both fire and topclipping affect sprouting of shortleaf × loblolly pine F1 hybrids compared to their parent open-pollinated populations during their third growing season. A factorial combination of top-clipping (hand pruners) and girdling by fire (propane torch) was conducted on November 2010, January, March, and April 2011 and sprouting response was measured after the growing season. Survival of topkilled shortleaf pine (94 %) was greatest followed by hybrid (78 %) and loblolly pine (35 %). However, species effects varied with topkill treatment and treatment date because survival was relatively lower for loblolly and hybrid pines in the burn-only as well as the November and April treatment dates while survival of shortleaf pine was consistently high. The number of sprouts was greatest for shortleaf (32.3) intermediate for hybrid (23.8) and lowest for loblolly pine (12.0). Overall, 83 % of shortleaf pine, 35 % of hybrid pine, and 5 % of loblolly pine exhibited a basal crook. The height from ground line to the lowest sprout was shortest for shortleaf (3.5 mm), intermediate for hybrids (7.7 mm), and largest for loblolly pine (21.3 mm). While the hybrid saplings exhibited intermediate performance in survival, sprouting capacity, and crooking, pure shortleaf pine were superior and are probably better suited to recover from fire.

Fire History in the Cherokee Nation of Oklahoma

The role of humans in historic fire regimes has received little quantitative attention. Here, we address this inadequacy by developing a fire history in northeastern Oklahoma on lands once occupied by the Cherokee Nation. A fire event chronology was reconstructed from 324 tree-ring dated fire scars occurring on 49 shortleaf pine (Pinus echinata) remnant trees. Fire event data were examined with the objective of determining the relative roles of humans and climate over the last four centuries. Variability in the fire regime appeared to be significantly influenced by human population density, culture, and drought. The mean fire interval (MFI) within the 1.2 km2 study area was 7.5 years from 1633 to 1731 and 2.8 years from 1732 to 1840. Population density of Native American groups including Cherokee was significantly correlated (r = 0.84) with the number of fires per decade between 1680 and 1880. Coincident with the Removal of the Cherokee and other native peoples from the eastern United States and immigrations into northeast Oklahoma, the MFI decreased to 1.8 years. After 1925 fire intervals were considerably lengthened (MFI = 16 years) due to fire suppression and decreased fire use until the recent prescribed burning by The Nature Conservancy. Many of the historic fire years that were previously shown to be synchronous across Missouri and Arkansas during drought years were also fire years at this site. Overall the frequency of fires was weakly associated with drought compared to human population density.

Planting Deep Increases Early Survival and Growth of Pinus echinata Seedlings

Two studies were established to determine the effects of planting depth on early performance of bareroot shortleaf pine seedlings (Pinus echinata). The studies involved planting seedlings either with the root-collar slightly below the groundline (GL) or with the root-collar planted about 11 cm below the soil surface (DEEP). After transplanting, DEEP seedlings had about 7.9 cm of shoot remaining aboveground. In one study, seedlings were planted in open sand pits where seedlings received 352 mm of rain by April 30. The second study involved planting seedlings in boxes (containing sand) in a roofed shade-house. Without rain, survival of DEEP seedlings in April was 96% which was significantly greater (P>F =0.007) than survival of GL seedlings (67%). With rainfall, survival (95%) was the same for both planting depths (P>F = 0.39). Therefore, planting seedlings with the root-collar level with the soil surface can, in some years, increase mortality. This might help explain why bareroot survival of shortleaf pine in some forest districts averages less than 80%.

Comparing Predicted Historical Distributions of Tree Species Using Two Tree-based Ensemble Classification Methods

Fine scale spatial mapping of historical tree records over large extents is important for determining historical species distributions. We compared performance of two ensemble methods based on classification trees, random forests, and boosted classification, for mapping continuous historical distributions of tree species. We used a combination of soil and terrain predictor variables to predict species distributions for 21 tree species, or species groups, from historical tree surveys in the Missouri Ozarks. Mean true positive rates and AUC values of all species combined for random forests and boosted classification, at a modeling prevalence and threshold of 0.5, were similar and ranged from 0.80 to 0.84. Although prediction probabilities were correlated (mean r = 0.93), predicted probabilities from random forests generated maps with more variation within subsections, whereas boosted classification was better able to differentiate the restricted range of shortleaf pine. Both random forests and boosted classification performed well at predicting species distributions over large extents. Comparison of species distributions from two or more statistical methods permits selection of the most appropriate models. Because ensemble classification trees incorporate environmental predictors, they should improve current methods used for mapping historical trees species distributions and increase the understanding of historical distributions of species.

Predicting litter and live herb fuel consumption during prescribed fires in native and old-field upland pine communities of the southeastern United States

The ability to predict fuel consumption during fires is essential for a wide range of applications, including estimation of fire effects and fire emissions. This project identified predictors of fuel consumption for the dominant fuel bed components (litter (&lt;0.6-cm diameter dead material) and live herbs) during 217 prescribed fires in native longleaf pine ( Pinus palustris Mill.) and old-field loblolly pine ( Pinus taeda L.) – shortleaf pine ( Pinus echinata Mill.) communities in the southeastern United States. Additionally, these data were used to validate the First Order Fire Effects Model (FOFEM) fuel consumption computer model using custom and default fuel loads. Regression models using empirical data suggested that litter and live herb fuel consumption can be predicted by prefire litter and live herb fuel loads, litter and live herb fuel moisture, litter fuel bed bulk density, season of burn, years since fire, days since last rain ≥0.64 cm, relative humidity, energy release component, community type, pine and hardwood basal areas, and the Keetch–Byram drought index. FOFEM’s prediction of fuel consumption for litter, live herbs, and duff combined using default fuel loads was 1.5 times the measured fuel consumption (where duff fuel load was zero). Refinement of FOFEM’s fuel load and consumption calculations in the studied community types using the newly collected data and suggestions for model improvement would provide more accurate air quality inventories and assist in guiding appropriate regulation of prescribed fire.

Hybridization Leads to Loss of Genetic Integrity in Shortleaf Pine: Unexpected Consequences of Pine Management and Fire Suppression

Hybridization between shortleaf pine and loblolly pine is causing loss of genetic integrity (the tendency of a population to maintain its genotypes over generations) in shortleaf pine, a species already exhibiting dramatic declines due to land-use changes. Recent findings indicate hybridization has increased in shortleaf pine stands from 3% during the 1950s to 45% for present-day natural regeneration. This drastic increase in hybridization is likely because of increased and wide-spread planting of loblolly pine and reduced selection pressure against loblolly pine and hybrids caused by fire suppression. Because shortleaf pine is more fire and drought tolerant than loblolly pine, loss of genetic integrity of shortleaf pine may reduce the resiliency and adaptability of southeastern conifer forests in the face of climate change and other stressors. Loblolly pine may also be at risk, with hybrids increasing in natural stands of loblolly pine from 4% in the 1950s to 27% at present.

Effects of Pythium Species and Time in Cold Storage on the Survival of Bareroot and Container-Grown Southern Pine Seedlings

Cold storing bareroot southern pine (Pinus spp.) seedlings for greater than one week after lifting in the fall can lead to poor outplanting survival when compared to seedlings that are lifted and stored in winter. In contrast, container-grown seedlings typically do not experience adverse effects from storing for periods greater than one week. The practice of lifting bareroot seedlings can cause wounds to root systems, which could allow soil-borne pathogens such as Pythium species to be used as infection sites. Once seedlings are placed in storage, the cool, moist environment may be conducive for zoospore activity, leading to root disease and outplanting failure. Bareroot and container-grown longleaf pine (Pinus palustris), loblolly pine (Pinus taeda), and slash pine (Pinus elliottii) and container-grown shortleaf pine (Pinus echinata) were inoculated with either Pythium dimorphum or Pythium irregulare, cold-stored for 3, 4, 6, or 12 weeks, and outplanted. Both Pythium species reduced survival of bareroot longleaf pine but not bareroot slash pine. Length of storage decreased survival for both seedling stock types. Pythium species did not affect the survival of container-grown seedlings. These results suggest that P. dimorphum and P. irregulare are more virulent to bareroot longleaf pine than the other pine species tested.

Restoration of shortleaf pine (Pinus echinata)-hardwood ecosystems severely impacted by the southern pine beetle (Dendroctonus frontalis)

In the Southern Appalachian Mountains of eastern USA, pine-hardwood ecosystems have been severely impacted by the interactions of past land use, fire exclusion, drought, and southern pine beetle (SPB, Dendroctonus frontalis). We examined the effects of restoration treatments: burn only (BURN); cut+burn on dry sites (DC+B); cut+burn on sub-mesic sites (MC+B); and reference sites (REF; no cutting or burning) on shortleaf pine-hardwood forests. We also evaluated the effectiveness of seeding native bluestem grasses. Structural (down wood, live and dead standing trees, shrubs, herbaceous layer) and functional (forest floor mass, C, and N; soil C, N, P, and cations; and soil solution N and P) attributes were measured before and the first and second growing seasons after treatment. We used path analysis to test our conceptual model that restoration treatments will have direct and indirect effects on these ecosystems. Total aboveground mass loss ranged from 24.33Mgha−1 on the BURN to 74.44Mgha−1 on the DC+B treatment; whereas, REF gained 13.68Mgha−1 between pre-burn and post-burn. Only DC+B sites had increased soil NO3–N, NH4–N Ca, Mg, and PO4–P and soil solution NO3–N, NH4–N, O–PO4 for several months.We found a significant increase in the density of oak species (Quercus alba, Q. coccinea, Q. montana, Q. rubra, and Q. velutina) on all burn treatments. However, oaks accounted for a smaller proportion of the total stem density than red maple, other tree species, and shrubs. The high densities of woody species other than oaks, coupled with the fast growth rates of some of these species, suggests that oaks will continue to be at a competitive disadvantage in these pine-hardwood communities through time, without further intervention. Pine regeneration was not improved on any of our burned sites with little to no recruitment of pines into the understory after two years and the pine saplings that were present before the burns were killed by fire on all sites. We found an increase in herbaceous layer cover and richness on all fire treatments. DC+B had higher bluestem grass cover than the other treatments, and it was the only treatment with increased bluestem grass cover between the first (2.96%, SE=0.29) and second (6.88%, SE=0.70) growing seasons. Our path model showed that fire severity explained a large proportion of the variation in overstory response; and fire severity and overstory response partially explained soil NO3–N. These variables, directly and indirectly, explained 64% of the variation in soil solution NO3–N at 30cm soil depth (within the rooting zone for most plants). We found a good-fit path model for herbaceous layer response in the second growing season, where fire severity had direct effects on overstory and herbaceous layer responses and indirect effects on herbaceous layer response mediated through overstory response. Our path model explained 46% and 42% of the variation in herbaceous layer cover and species richness, respectively.