Fire Study - Research Project Summary

Early postfire effects of a prescribed fire in the southern Appalachians

Written

August, 2007

Study Authors

Elliott et al.

Contributors

Corey Gucker - 1st Compiler

Fire Study Type

Research Project Summary

Gucker, Corey L, comp. 2007. Early postfire effects of a prescribed fire in the southern Appalachians of North Carolina. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://research.fs.usda.gov/feis/fire-studies/elliott-et-al-2007

Source

Unless otherwise indicated, the information in this Research Project Summary comes from the following paper:

Elliott, Katherine J.; Hendrick, Ronald L.; Major, Amy E.; Vose, James M.; Swank, Wayne T. 1999. Vegetation dynamics after a prescribed fire in the southern Appalachians. Forest Ecology and Management. 114(2-3): 199-213 [1].

Species Included in the Summary

Common names are used throughout this summary. For a complete list of the common and scientific names of species discussed in this summary, see the Appendix.

Fire effects were studied in the Wine Spring Creek Watershed in the southern Appalachian Mountains of western North Carolina's Nantahala National Forest (35 °N latitude, 83 °W longitude).

Site Description

The prescribed fire burned a south-facing slope of 35% to 60% at 1,500 to 1,700 m elevation. Fine-loamy, mixed, mesic Typic Hapludult and loamy, mixed, mesic Lithic Dystrochrept soils occur at the upper slope and ridge. Coarse-loamy to loamy-skeletal, mixed, mesic Typic Haplumbrept soils occur at the mid- and low-slope positions. Annual temperature and precipitation in this area average 10.4 °C and 1,900 mm, respectively.

At the low-slope position, researchers described the vegetation as a mesic, near-riparian community. Overstory dominants were red maple and hickory. Midslope supported a dry, mixed-oak community dominated by chestnut oak, scarlet oak, red maple, hickory, and sourwood. Ridges and upper slopes were xeric pitch pine/chestnut oak forests. Communities had not burned for at least 70 years prior to this prescribed fire.

Historic fire regime characteristics for Appalachian oak-hickory-pine and eastern dry oak communities are summarized below:

Fire regime information on the vegetation community studied in this Research Project Summary. Fire regime characteristics are taken from the LANDFIRE Rapid Assessment Vegetation Model [3]. This vegetation model was developed by local experts using available literature and expert opinion.
Vegetation Community (Potential Natural Vegetation Group)	Fire severity*	Fire regime characteristics
Vegetation Community (Potential Natural Vegetation Group)	Fire severity*	Percent of fires	Mean interval (years)	Minimum interval (years)	Maximum interval (years)
Appalachian oak-hickory-pine	Replacement	3%	180	30	500
	Mixed	8%	65	15	150
	Surface or low	89%	6	3	10
Oak (eastern dry-xeric)	Replacement	6%	128	50	100
	Mixed	16%	50	20	30
	Surface or low	78%	10	1	10
Fire Severities: Replacement=Any fire that causes greater than 75% top removal of a vegetation-fuel type, resulting in general replacement of existing vegetation; may or may not cause a lethal effect on the plants. Surface or low=Any fire that causes less than 25% upper layer replacement and/or removal in a vegetation-fuel class but burns 5% or more of the area. Mixed*=Any fire burning more than 5% of an area that does not qualify as a replacement, surface, or low-severity fire; includes mosaic and other fires that are intermediate in effects [2,3].

Plant Phenology

Phenology of the vegetation was not described prior to the April 1995 prescribed fire; some vegetation may have initiated growth by this time. Without the precise date of the fire and climate conditions in the months prior, it is difficult to describe the phenology of the vegetation as a whole.

The Forest Service, US Department of Agriculture, burned this southern slope to promote oak and pitch pine regeneration in the long unburned and "degraded" community. Increased severity was predicted as the fire burned upslope. Researchers hoped that burned sites would have increased forage production, decreased mountain-laurel abundance, and increased pitch pine and oak (Quercus spp.) recruitment.

Strip head fires were used to burn the approximately 300-ha study area. On the ridge, the fire was stand replacing, and the understory was consumed [1,5]. At the low-slope position, the fire was patchy and burned only the understory. Aboveground flame temperatures and heat penetration were measured using heat-sensitive painted tiles. Flame temperatures were measured 1 and 2 m above ground. Belowground heat penetration was measured at the forest floor and in the mineral soil. Temperatures produced and heat penetration depths are summarized below [5].

Above- and belowground temperatures produced by the fire at low, mid-, and ridge positions.
Slope position	Flame temperature (°C)		Average (range) of soil heat penetration (mm)
Slope position	1 m	2 m	45 °C	59 °C
Low slope	<52	<52	0.5 (0-3)	0.6 (0-4)
Mid-slope	<52 to 160	<52 to 90	18.2 (1-52)	16.8 (4-52)
Ridge	<52 to >800	<52 to >800	27.5 (9-55)	24.0 (7-55)

Fire Season/Severity Classification

Spring/low to high

Overstory dominance on the ridge was unchanged by the fire. Pitch pine, chestnut oak, and scarlet oak dominated the canopy vegetation both before and after the fire. Density- and basal area-based species richness were significantly (P≤0.05) reduced by the fire. Decreased richness was a result of American chestnut, blackgum, black locust, sassafras, and eastern hemlock mortality. Nearly all canopy species had decreased frequency, density, and basal area after the fire.

Pre- and postfire frequency, density, and basal area of canopy species on the ridge. *Values with the same letters are not significantly different (P≤0.05) between time periods.
Time since fire	Frequency (%)		Density (stems/ha)		Basal area (m²/ha)
Time since fire	Prefire	3 mo	Prefire	3 mo	Prefire	3 mo
American chestnut	21	0	29	0	0.11	0
blackgum	14	0	29	0	0.17	0
black locust	7	0	7	0	0.01	0
Carolina silverbell	7	7	7	7	0.15	0.15
chestnut oak	93	64	239	146	5.22	3.33
common serviceberry	43	21	109	70	0.97	0.67
eastern hemlock	7	0	7	0	0.26	0
hickory	36	21	128	50	1.38	0.80
northern red oak	21	14	17	14	0.07	0.07
pitch pine	93	78	637	441	12.45	9.67
red maple	50	21	108	41	2.14	1.21
sassafras	7	0	3	0	0.01	0
scarlet oak	57	36	121	60	2.26	1.55
sourwood	50	50	96	77	1.60	1.40
white oak	7	7	7	7	0.02	0.02
Total	—	1,545a*	913b	26.84a	18.86b	—

The average percent mortality following the fire ranged from 18.5% to 30.6% for the dominant overstory species (pitch pine, chestnut oak, and scarlet oak). For associated overstory species, mortality ranged from 25.0% to 100%.

Average mortality of overstory species on burned ridge.
Species	N	Mortality (%)	SE
American chestnut	3	100	0
chestnut oak	12	30.6	13.3
common serviceberry	4	25.0	25.0
hickory	5	57.5	17.5
pitch pine	12	18.5	8.6
red maple	7	42.8	20.2
scarlet oak	8	29.2	16.0

Total density and basal area of understory vegetation on the ridge was significantly (P≤0.05) lower following the fire. However, total density and basal area increased with increased time since fire, although basal area and density had not recovered to prefire levels within a year of the fire. Mountain-laurel density and basal area were significantly (P≤0.05) lower after burning. Pitch pine understory density increased after the first postfire year. Black locust, chestnut oak, and scarlet oak densities were significantly (P≤0.05) greater after the ridge burned. White oak, northern red oak, and black oak were not present in the understory after the fire.

Pre- and postfire frequency, density, and basal area of understory species on the ridge. *Values with the same letters are not significantly different (P≤0.05) between time periods.
Time since fire	Frequency (%)			Density (stems/ha)			Basal area (m²/ha)
Time since fire	Prefire	3 mo	1 yr, 3 mo	Prefire	3 mo	1 yr, 3 mo	Prefire	3 mo	1 yr, 3 mo
Understory species (≥1 cm basal diameter, <5 cm DBH)
American chestnut	21	0	21	952	0	413	0.536	0	0.184
black locust	14	0	28	10b*	0	813a	0.002	0	0.119
black oak	36	0	0	19	0	0	0.010	0	0
chestnut oak	50	14	21	505b	25c	720a	0.244	0.024	0.097
deerberry	0	0	7	0	0	317	0	0	0.025
common serviceberry	36	7	7	76a	6b	3b	0.027	0.008	0.001
flame azalea	7	0	7	159a	0	19b	0.038	0	0.002
hickory	14	0	14	82	0	161	0.022	0	0.025
mountain-laurel	100	21	14	8,651a	248b	168b	4.97a	0.127b	0.403b
northern red oak	36	0	0	368a	19b	0	0.187	0.002	0
pitch pine	21	0	7	165	0	317	0.212	0	0.035
red maple	43	14	14	168	13	82	0.045	0.010	0.011
sassafras	36	7	36	321b	82c	571a	0.050	0.191	0.102
scarlet oak	50	7	50	295b	6c	1,997a	0.078b	0.008b	0.222a
sourwood	7	0	14	10	10	29	0.001	0.001	0.004
sweet birch	0	0	7	0	0	79	0	0	0.006
white oak	28	0	0	397	0	0	0.096	0	0
Total	—	—	12,178a	409c	5,692b	6.522a	0.371c	1.236b	—

The number of pitch pine seedlings increased by 358% in the third postfire month but was 35% of the prefire number a year following the fire. Common serviceberry seedlings increased by 350% a year after the fire.

The coverage of ground layer vegetation on the ridge slightly exceeded prefire levels by the first postfire year. Black oak, white oak, sourwood, and black locust were present in the prefire surface layer but were not present a year after the fire. Red maple, chestnut oak, and sassafras had greater cover after than before the fire. Blueberry, buffalo nut, mountain sweetpepperbush, and flame azalea all had greater than prefire cover levels 1 year after the fire. Pitch pine, present with low cover in prefire vegetation, was absent from the ground layer after the fire. Most herbs and vines present in the prefire community had increased cover in the first postfire year. Sedge and goldenrod species present in the prefire community, however, were absent from the community a year after fire. Bedstraw, western brackenfern, greater tickseed, common goldstar, bellwort, Michaux's saxifrage, New York fern, plains snakecotton, little bluestem, and panicgrass were only found on the ridge after the fire.

Pre- and postfire cover of herb-layer vegetation on the ridge.
Time since fire	Prefire	3 mo	1 year, 3 mo
Ground layer species	Cover (%)
Trees
American chestnut	0	0.7	0
black locust	0.02	0.5	0
black oak	0.06	0.08	0
chestnut oak	0.25	0.10	1.29
common serviceberry	0.06	0.08	0.08
northern red oak	0.08	0.08	0.25
pitch pine	0.10	0.08	0
red maple	0.25	0.08	1.17
sassafras	0.10	0.25	2.88
scarlet oak	0.08	0.03	0.21
sourwood	0.02	0.5	0
white oak	0.03	0	0
Shrubs
blackberry	0	0	0.12
black huckleberry	1.03	1.88	0.96
blueberry	2.28	2.28	5.17
buffalo nut	0.18	0.08	0.67
flame azalea	0.02	0.25	1.46
mountain-laurel (clone density = #/ha)	28.0	3.67 (11,307)	11.4 (9,285)
mountain sweetpepperbush	0.07	0.03	0.96
smooth sumac	0	0.03	0
Forbs
bedstraw	0	0.13	1.33
bellwort	0	0.03	0
common goldstar	0	0.05	0
beetleweed	0.40	0.10	0.92
greater tickseed	0	0.05	0
goldenrod	0.02	0	0
Indian cucumber	0.02	0	0.12
Michaux's saxifrage	0	0.02	0.29
narrowleaf cowwheat	0.22	0.02	1.17
New York fern	0	0.02	0
plains snakecotton	0	0	0.12
trailing arbutus	0.55	0.10	0.33
western brackenfern	0	0.10	0.42
Graminoids
little bluestem	0	0.23	0.54
panicgrass	0	0	2.75
sedge	1.08	0.10	0
Vines
greenbrier	0.63	0.40	2.71
Total	10.6	37.7	—
Species richness	24	33	26
Pielou evenness index	0.32	0.61	0.77

The fire at the midslope position was less severe than that at the ridge. Total pre- and postfire overstory density and basal area were not significantly (P≤0.05) different, and pre- and postfire differences in individual overstory species frequency, density, and basal area were little to none.

Pre- and postfire frequency, density, and basal area of overstory species at the midslope position. *Values with the same letters are not significantly different (P≤0.05) between time periods.
Time since fire	Prefire	3 mo	Prefire	3 mo	Prefire	3 mo
Species	Frequency (%)		Density (stems/ha)		Basal area (m²/ha)
blackgum	22	22	156	156	0.99	0.99
black locust	56	44	89	64	0.66	0.53
Carolina silverbell	11	11	44	33	0.26	0.23
chestnut oak	56	44	99	94	6.47	6.44
cucumber-tree	11	11	5	5	0.04	0.04
common serviceberry	33	33	38	38	0.27	0.27
eastern hemlock	22	22	22	22	0.94	0.94
hickory	67	67	173	178	2.84	2.89
red maple	200	100	626	606	9.01	9.02
scarlet oak	22	22	38	27	4.00	3.91
sourwood	67	67	153	137	3.16	3.11
sweet birch	22	22	5	5	0.03	0.03
Total	—	—	1,448a*	1,365a	28.69a	28.42a

Total density and basal area of midslope vegetation was significantly (P≤0.05) reduced by the fire. Red maple, American chestnut, mountain-laurel, and sourwood had significantly (P≤0.05) lower density and basal area after the fire. Hickory, Carolina silverbell, cucumber-tree, buffalo nut, white oak, black locust, and eastern hemlock were present in the prefire community but were not present 3 months after the fire. Rosebay, a dominant in the prefire understory, remained dominant after the fire with relatively little change in density or basal area after the fire.

Pre- and postfire frequency, density, and basal area of understory species at the midslope position. *Values with the same letters are not significantly different (P≤0.05) between time periods.
Time since fire	Prefire	3 mo	Prefire	3 mo	Prefire	3 mo
Understory species (≥1 cm basal diameter, <0.5 cm DBH)	Frequency (%)		Density (stems/ha)		Basal area (m²/ha)
American chestnut	44	11	573a*	20b	0.127a	0.002b
blackgum	11	11	123a	10b	0.012a	0.012a
black locust	11	0	15	0	0.008	0
buffalo nut	11	0	123	0	0.047	0
Carolina silverbell	22	0	494	0	0.064	0
chestnut oak	11	11	25	5	0.012	<0.001
cucumber-tree	11	0	123	0	0.019	0
eastern hemlock	11	0	10	0	0.002	0
hickory	11	0	5	0	0.006	0
mountain-laurel	67	11	4,691a	123b	4.497a	0.422b
northern red oak	22	0	20	0	0.010	0
red maple	56	22	326a	15b	0.494a	0.019a
rosebay	22	11	1,605a	1,358a	7.231a	7.789a
sourwood	22	11	138a	25b	0.015a	0.002b
white oak	22	0	247	0	0.020	0
Total	—	8,518a	1,556b	12.56a	8.25b	—

The fire at the low-slope position was less severe than that at the ridge or midslope. Total pre- and postfire canopy density and basal area were not significantly (P≤0.05) different, and pre- and postfire differences in individual species frequency, density, and basal area were little to none.

Pre- and postfire frequency, density, and basal area of overstory species at the low-slope position. *Values with the same letters are not significantly different (P≤0.05) between time periods.
Time since fire	Prefire	3 mo	Prefire	3 mo	Prefire	3 mo
Species	Frequency (%)		Density (stems/ha)		Basal area (m²/ha)
American chestnut	11	11	11	11	0.001	0.001
American witchhazel	11	11	11	11	0.02	0.02
blackgum	11	11	22	22	0.07	0.07
black locust	22	22	22	22	0.94	0.94
Carolina silverbell	22	11	44	15	0.13	0.05
chestnut oak	33	33	32	32	0.63	0.62
cucumber-tree	11	11	30	39	0.16	0.18
common serviceberry	44	33	47	37	0.28	0.24
eastern hemlock	89	89	238	243	3.80	3.87
hickory	78	78	186	167	6.64	6.62
northern red oak	33	33	21	21	0.61	0.63
red maple	89	89	333	328	6.54	6.59
sassafras	11	11	5	5	0.07	0.07
scarlet oak	33	33	21	21	3.12	3.16
sugar maple	11	11	5	5	0.04	0.04
sourwood	11	11	22	22	0.78	0.78
striped maple	44	44	64	64	0.49	0.50
white oak	22	22	36	36	2.88	2.90
tuliptree	22	22	15	15	0.48	0.51
Total	—	1,167a*	1,117a	27.72a	27.82a	—

The low-severity fire at the low slope increased total understory stem density, though not significantly. Hawthorn, which was not present before the fire, had a density of 123 stems/ha 3 months after the fire. Postfire densities of American chestnut, white ash, Carolina silverbell, and buffalo nut were more than double the prefire densities 3 months after spring burning. Densities of flame azalea, eastern hemlock, northern red oak, and hickory decreased by more than half, and mountain magnolia and chestnut oak were absent after the fire.

Pre- and postfire frequency, density, and basal area of canopy species at the low-slope position. *Values with the same letters are not significantly different (P≤0.05) between time periods.
Time since fire	Prefire	3 mo	Prefire	3 mo	Prefire	3 mo
Understory species (≥1 cm basal diameter, <0.5 cm DBH)	Frequency (%)		Density (stems/ha)		Basal area (m²/ha)
American chestnut	33	44	138	592	0.044	0.115
buffalo nut	11	33	123	370	0.051	0.135
Carolina silverbell	33	33	59	138	0.022	0.031
chestnut oak	11	0	5	0	<0.001	0
cucumber-tree	33	44	207	301	0.056	0.074
common serviceberry	33	22	30	54	0.016	0.037
eastern hemlock	22	22	143	20	0.4	0.019
flame azalea	11	11	864	370	0.32	0.200
hawthorn	0	11	0	123	0	0.014
hickory	11	11	40	10	0.006	0.007
mountain magnolia	11	0	5	0	<0.001	0
northern red oak	22	22	133	64	0.026	0.005
red maple	22	22	30	44	0.010	0.021
sugar maple	33	33	138	158	0.026	0.032
striped maple	22	22	133	153	0.018	0.026
sourwood	11	11	5	10	0.002	<0.001
sweet birch	11	11	5	10	<0.001	<0.001
white ash	11	22	15	79	0.005	0.017
white oak	22	11	10	34	0.001	0.003
tuliptree	22	33	69	118	0.011	0.020
Total	—	2,153a*	2,652a	1.015a	0.758a	—

This southern slope was burned to encourage oak and pitch pine regeneration in the long unburned and "degraded" community. Researchers hoped that burned sites would have increased forage production and decreased mountain-laurel abundance. On the ridge, the abundance of red maple was reduced by the fire, and growth and recruitment of several oak species increased in the understory. The fire decreased mountain-laurel density and basal area on the ridge and midslope positions. However, without later postfire sampling it is unclear whether or not pitch pine and oak regeneration will be successful before mountain-laurel density and basal area recover to prefire levels. The early mortality of postfire pitch pine seedlings suggests that successful pitch pine regeneration may require another prescribed fire or canopy-opening disturbance. Low postfire precipitation, high postfire basal area, and/or the lack of litter and duff consumption may have increased postfire pitch pine seedling mortality. In the understory, blueberries, black huckleberry, little bluestem, and panicgrasses increased in number, increasing wildlife forage in the area.

While the spring fire in the southern Appalachians increased wildlife forage and encouraged oak regeneration, it did not allow for successful regeneration of pitch pine. A high-severity fire, burning when pitch pine cone crops are good, may produce an environment conducive to successful pitch pine recruitment. Researchers suggest an initial high-severity fire and subsequent low-severity fires at 5- to 10-year intervals may encourage pitch pine and oak dominance and limit mountain-laurel density.

Table A1: Common and scientific names of species mentioned in this summary.

This Research Project Summary contains fire response information on the following species. For further information, search FEIS reviews for listed species.
Common name	Scientific name
striped maple	Acer pensylvanicum
red maple	Acer rubrum
sugar maple	Acer saccharum
common serviceberry	Amelanchier arborea
sweet birch	Betula lenta
sedge	Carex spp.
hickory	Carya spp.
American chestnut	Castanea dentata
mountain sweetpepperbush	Clethra acuminata
greater tickseed	Coreopsis major
hawthorn	Crataegus spp.
trailing arbutus	Epigaea repens
white ash	Fraxinus americana
plains snakecotton	Froelichia floridana
beetleweed	Galax urceolata
bedstraw	Galium spp.
black huckleberry	Gaylussacia baccata
Carolina silverbell	Halesia carolina
American witchhazel	Hamamelis virginiana
common goldstar	Hypoxis hirsuta
mountain-laurel	Kalmia latifolia
tuliptree	Liriodendron tulipifera
cucumber-tree	Magnolia acuminata
mountain magnolia	Magnolia fraseri
Indian cucumber	Medeola virginiana
narrowleaf cowwheat	Melampyrum lineare
blackgum	Nyssa sylvatica
sourwood	Oxydendrum arboreum
panicgrass	Panicum spp.
pitch pine	Pinus rigida
western brackenfern	Pteridium aquilinum
buffalo nut	Pyrularia pubera
white oak	Quercus alba
scarlet oak	Quercus coccinea
chestnut oak	Quercus prinus
northern red oak	Quercus rubra
black oak	Quercus velutina
smooth sumac	Rhus glabra
flame azalea	Rhododendron calendulaceum
rosebay	Rhododendron maximum
black locust	Robinia pseudoacacia
blackberry	Rubus spp.
sassafras	Sassafras albidum
Michaux's saxifrage	Saxifraga michauxii
little bluestem	Schizachyrium scoparium
greenbrier	Smilax spp.
goldenrod	Solidago spp.
New York fern	Thelypteris noveboracensis
eastern hemlock	Tsuga canadensis
bellwort	Uvularia spp.
deerberry	Vaccinium stamineum
blueberry	Vaccinium spp.

1. Elliott, Katherine J.; Hendrick, Ronald L.; Major, Amy E.; Vose, James M.; Swank, Wayne T. 1999. Vegetation dynamics after a prescribed fire in the southern Appalachians. Forest Ecology and Management. 114(2-3): 199-213. [30079]

2. Hann, Wendel; Havlina, Doug; Shlisky, Ayn; [and others]. 2005. Interagency fire regime condition class guidebook. Version 1.2, [Online]. In: Interagency fire regime condition class website. U.S. Department of Agriculture, Forest Service; U.S. Department of the Interior; The Nature Conservancy; Systems for Environmental Management (Producer). Variously paginated [+ appendices]. Available: http://www.frcc.gov/docs/1.2.2.2/Complete_Guidebook_V1.2.pdf [2007, May 23]. [66734]

3. LANDFIRE Rapid Assessment. 2005. Reference condition modeling manual (Version 2.1), [Online]. In: LANDFIRE. Cooperative Agreement 04-CA-11132543-189. Boulder, CO: The Nature Conservancy; U.S. Department of Agriculture, Forest Service; U.S. Department of the Interior (Producers). 72 p. Available: http://www.landfire.gov/downloadfile.php?file=RA_Modeling_Manual_v2_1.pdf [2007, May 24]. [66741]

4. LANDFIRE Rapid Assessment. 2007. Rapid assessment reference condition models. In: LANDFIRE. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Lab; U.S. Geological Survey; The Nature Conservancy (Producers). Available: http://www.landfire.gov/models_EW.php [66533]

5. Vose, James M.; Swank, Wayne T.; Clinton, Barton D.; Knoepp, Jennifer D.; Swift, Lloyd W. 1999. Using stand replacement fires to restore southern Appalachian pine-hardwood ecosystems: effects on mass, carbon, and nutrient pools. Forest Ecology and Management. 114(2-3): 215-226. [30149]

Last updated April 27, 2026

Early postfire effects of a prescribed fire in the southern Appalachians

Citation

Introduction

Source

Species Included in the Summary

Study Location

Site Description

Prefire Plant Community and Fuels

Plant Phenology

Fire Description

Fire Season/Severity Classification

Fire Effects

Fire Management Implications

Appendix

Table A1: Common and scientific names of species mentioned in this summary.

References