Sassafras albidum, sassafras
Sullivan, Janet. 1993. Sassafras albidum, sassafras. 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/species-reviews/sasalb
| Abbreviation | Common Name | Scientific Name | Classification | Status |
|---|---|---|---|---|
| Plants | ||||
| SASALB | sassafras | Sassafras albidum | Life Form: Plants/Shrub, Plants/Tree Kingdom: Plantae Class: Dicot Order: Laurales Family: Lauraceae Genus: Sassafras | Fed. Protected: No Nativity: Native Invasiveness: Noninvasive |
Taxonomy
The currently accepted scientific name of sassafras is Sassafras albidum (Nutt.) Nees. [41,61].
Some authorities consider red sassafras [S. a. var. molle (Raf.) Fern.] a distinct variety [8,30,82]; other authors consider it synonymous with the typical variety [53,61,68].
Synonyms
- S.variifolium (Salisb.) K. & Ze.
- S. sassafras (L.) Karsten
- S. officinale (Nees. & Eberm.)
- S. triloba Raf.
- S. triloba var. mollis Raf.
Other Common Names
white sassafras, common sassafras, ague tree, cinnamon wood, smelling stick, saloop, gumbo file, mitten tree
General Distribution
Sassafras occurs from southwestern Maine west to extreme southern Ontario and central Michigan; southwest to Illinois, Missouri, eastern Oklahoma, and eastern Texas; and east to central Florida. It is extinct in southeastern Wisconsin, but its range is extending into northern Illinois [41].
States
- United States: AL AR CT DE FL GA IL IN IA KS KY LA ME MD MA MI MS MO NH NJ NY NC OH OK PA RI SC TN TX VT VA WV
Site Characteristics
Sassafras on a rocky ridge, Pisgah National Forest, Burke County, North Carolina. (CC0 1.0)
Sassafras occurs on nearly all soil types within its range, but is best developed on moist, well-drained sandy loams in open woodlands [41]. Optimum soil pH ranges from 6.0 to 7.0, but sassafras also occurs on acid sands in eastern Texas [41,75]. It is intolerant of poorly drained soils [32]. Sassafras occurs along fence rows and on dry ridges and upper slopes, particularly following fire [41]. Sassafras occurs at elevations ranging from Mississippi River bottomlands up to 4,000 feet (1,220 m) in the southern Appalachian Mountains, occasionally up to 4,900 feet (1,500 m) [24,41].
Plant Communities
The sassafras-persimmon (Diospyros virginiana) cover type is a successional type common on abandoned farmlands throughout its range. Sassafras is a common component of the bear oak (Quercus ilicifolia) type, which is a scrub type on dry sites along the Coastal Plain [41]. In dry pine-oak forests, sassafras sprouts prolifically and is a shrub-layer dominant [72]. It achieves short-term dominance by producing extensive thickets where few other woody plants can establish [32]. In the northern parts of its range, sassafras occurs in the understory of open stands of aspen (Populus spp.) and in northern pin oak (Q. ellipsoidalis) stands [41].
Common tree associates of sassafras not previously mentioned include sweetgum (Liquidambar styraciflua), flowering dogwood (Cornus florida), elms (Ulmus spp.), hickories (Carya spp.), and American beech (Fagus grandifolia). Minor associates include American hornbeam (Carpinus caroliniana), eastern hophornbeam (Ostrya virginiana), and pawpaw (Asimina triloba). On poor sites, particularly in the Appalachian Mountains, sassafras is frequently associated with black locust (Robinia pseudoacacia), and sourwood (Oxydendron arboreum). In old fields with deep soils, sassafras commonly grows with elms, ashes (Fraxinus spp.), sugar maple (Acer saccharum), tuliptree (Liriodendron tulipifera), and oaks [41].
Sassafras is listed as a subdominant on subxeric and submesic sites in the following classification:
- Landscape ecosystem classification for South Carolina [51].
Botanical Description
Sassafras is a native, deciduous, aromatic tree or large shrub, with a flattened, oblong crown [41,83]. On the best sites, height ranges up to 98 feet (30 m) [41]. In the northern parts of its range, sassafras tends to be shrubby, especially on dry, sandy sites, and reaches a maximum of 40 feet (12 m) [49]. The bark of older stems is deeply furrowed, or irregularly broken into broad, flat ridges [38,83]. The variety of leaf shapes to be found on one individual is a distinctive trait of the species. Leaves can be entire, one-lobed, or two-lobed. The fruit is a drupe [41]. The root system is shallow, with prominent lateral roots. Root depth ranges from 6 to 20 inches (15-50 cm).
Raunkiaer Life Form (Raunkiaer 1934)
- Phanerophyte
Sassafras seedlings growing in deep litter, Cumberland Gap National Historic Park, Bell County, Kentucky. (CC0 1.0)
Seasonal Development
Depending upon latitude, sassafras flowers from March to May [24], and fruits ripen from June to September [68,76,77].
Regeneration Processes
Sexual reproduction: Sassafras is sexually mature by 10 years of age, and best seed production occurs between 25 and 50 years of age. Good seed crops are produced every 1 to 2 years. Seeds are dispersed by birds, water, and small mammals. Sassafras seeds are usually dormant until spring, but some germination occurs in the fall immediately following dispersal [41]. Stratification in sand for 30 days at 41 degrees Fahrenheit (5 deg C) breaks the natural dormancy. Average germination rate is around 85 percent [83]. Since sassafras seeds are relatively large, initial establishment is not highly dependent on available soil nutrients. Other factors appear to play a greater role. Seedling establishment occurred at higher than randomly expected frequencies on microsites with greater ground cover, less light, or deeper litter than other microsites [14]. Sassafras seeds were found in seed banks under red pine (Pinus resinosa), eastern white pine (P. strobus), and Virginia pine (P. virginiana) stands [6]. Sassafras seedling reproduction is usually sparse and erratic in wooded areas. In these areas, reproduction is usually vegetative [32,41].
Asexual reproduction: Sassafras forms dense thickets of root sprouts, and young trees sprout from the stump [41]. After clearcutting in upland hardwood stands (Indiana), 86.5 percent of sassafras regeneration was of seedling or seedling sprout origin; the remainder was of stump sprout origin [36].
Successional Status
Facultative Seral Species
Sassafras is a frequent pioneer in old fields, and is a member of seral stands in the Southeast [41]. In old-field succession in Tennessee, sassafras was a dominant member of a 15-year-old stand, and was not present in a 48-year-old stand [11]. In Virginia, sassafras persists to mid-successional stages with black locust, Virginia pine, pitch pine, eastern white pine, scarlet oak, blackjack oak, and post oak [86]. It also occurs in the canopy of old-growth forests in Illinois and Michigan [45,71]. In the Michigan stands sassafras decreased in relative density during a 20-year study [45]. The persistence of sassafras into later seres and climax stands may be a result of gap capture; in an old-growth forest in Massachusetts, older sassafras trees appear to be associated with hurricane and/or windthrow gaps. There was no evidence of fire disturbance in this forest [25]. Human activities and disturbance can foster sassafras establishment in old-growth stands. The relatively high abundance of sassafras under Virginia pine stands is associated with a greater frequency of tree-fall gaps under Virginia pine than under red pine or eastern white pine [6]. Sassafras seedlings in Table Mountain pine (Pinus pungens) stands are able to exploit canopy gaps at the expense of Table Mountain pine [87].
A detailed study of age structure in mixed forests in Virginia reveals another role for sassafras. In 45- to 80-year-old mixed hardwoods and mixed pine stands, sassafras seedlings and saplings occur in large numbers. They rarely survive more than 30 years except on moist sites. On relatively dry sites, sassafras does not survive long enough to occupy upper canopy positions. But since sassafras sprouts prolifically, there is a constant turnover of sassafras stems; older stems die back and are replaced by new ramets. Sassafras in the understory produces fruit under these conditions. In these stands, sassafras is apparently functioning as a dominant shrub [72].
In New Jersey, fragmented mixed oak forests were compared with forests that were continuous. Sassafras was present in 63 percent of the fragments, compared to 25 percent of the continuous stands [37].
Sassafras exhibits a positive response to overstory removal; overstory defoliation by gypsy moths results in an increase in the number of sassafras stems [1].
An unusual pure stand of sassafras was reported by Lamb [59] in 1923. This stand appeared to have remained essentially pure and intact for over 100 years. The trees were described as fully mature, slow growing, and the soil was very fertile. It is possible that the persistence of this stand, and the competitive success of sassafras in pioneer communities are related to the presence of terpenoid allelopathic substances in sassafras leaves. These substances affect, among other species, American elm (Ulmus americana) and box elder (Acer negundo). The susceptibility of these species appears to be related to their habit of germination immediately following dispersal. The toxic terpenes are washed off of summer leaves and are less concentrated in winter and spring when no fresh leaves are present [31,34].
Immediate Fire Effects
Low-severity fires kill seedlings and small saplings. Moderate- and high-severity fires injure mature trees, providing entry for pathogens [41,75]. In oak savanna in Indiana, sassafras showed significantly less susceptibility to low-severity fire than other species [4]. Sassafras exhibited 21 percent mortality of stems after prescribed fire in western Tennessee. This was the lowest mortality of all hardwoods present. Season of burning did not affect susceptibility [17].
Postfire Regeneration Strategy (Stickney 1989)
- Tree with adventitious-bud root crown/soboliferous species root sucker
- Ground residual colonizer (on-site, initial community)
- Initial-offsite colonizer (off-site, initial community)
- Crown residual colonizer (on-site, initial community)
Fire Adaptations
Sassafras is moderately resistant to fire damage to aboveground growth. It is also highly resilient to such damage; sassafras sprouts vigorously following top-kill, even after repeated fires [54]. In Indiana, sassafras occurs in black oak (Quercus velutina) stands with a mean fire interval of 11.1 years [47]. Sassafras establishment on these sites appears to be related to the frequency and severity of fire. Sassafras did not occur on sites which had burned more often (mean fire interval of 5.2 years). The stands with longer fire-free intervals burned more severely than those with shorter intervals. The more severe disturbance probably created more favorable conditions for sassafras seedling establishment [48].
Sassafras bark is less resistant to heat than chestnut oak (Quercus prinus), white oak (Q. alba), and northern red oak (Q. rubra); equally as resistant as hickory and red maple (Acer rubrum); and more resistant than witchhazel (Hamamelis virginiana), fire cherry (Prunus pensylvanica), serviceberry (Amelanchier spp.), and bear oak [20].
Plant Response to Fire
Sassafras occurs on charcoal hearths, which are patches of ground that were used for charcoal making. These areas are characterized by very poor soil structure. Sassafras on these sites shows poor growth [10].
The effects of annual and 5-year interval prescribed burning over a 27-year period in Tennessee has been reported. After 6 years, sassafras density was higher on annually burned plots than on unburned plots. The highest sassafras density occurred on the 5-year interval plots [80]. Sassafras gradually decreased with increasing canopy closure on the 5-year interval plots. By year 27, however, sassafras was eliminated from the annually burned plots. Sassafras was also eliminated from unburned plots; these plots developed closed canopies which are unfavorable to sassafras [19].
A large number of root sprouts occurred after sapling and small diameter sassafras trees were top-killed by fire in an Illinois post oak (Quercus stellata) stand [12]. Sprout production by top-killed sassafras was stimulated by prescribed fire, and greatly increased its cover in the shrub layer [13].
In Illinois, the number of small sassafras stems increased after a single winter prescribed fire from 9 percent frequency to 36 percent frequency. This increase was largely due to root sprouting by top-killed plants. The number of sassafras seedlings also increased after the same fire [3]. In Virginia, in Table Mountain pine stands that experienced a high-severity wildfire (98 percent top-kill), sassafras increased from 0 to 12.1 in relative importance in 1 year. Sassafras also increased on plots experiencing low-severity fire, but the difference in importance value was not as great [42].
In the absence of fire or other disturbances, sassafras frequency decreases with increasing canopy closure; the number of new sassafras seedlings also decreases with canopy closure [2,3].
Fire does not always lead to increased sassafras. Grelen [40] reported sassafras occurrence on unburned, young slash pine (Pinus elliottii) plots but not on plots burned annually, biennially, or triennially in March or May over the course of 12 years. In Florida, sassafras was found on unburned, 15-year-old old fields, but not on oldfield plots that were burned annually in February or March for 15 years [26].
The following Research Project Summaries provide information on prescribed fire use and postfire response of plant community species, including sassafras, that was not available when this species review was originally written:
- Effects of surface fires in a mixed red and eastern white pine stand in Michigan
- Early postfire effects of a prescribed fire in the southern Appalachians of North Carolina
- Early postfire response of southern Appalachian Table Mountain-pitch pine stands to prescribed fires in North Carolina and Virginia
- Early postfire response of Georgian Table Mountain pine stands burned under prescription at varying intensities
Fire Regimes
An increase in the frequency of sassafras in New Jersey forests since European settlement has been attributed, at least in part, to an increase in fire frequency [73].
The bear oak type, in which sassafras frequently occurs, is a product of periodic fire and droughty soils [44]. Sassafras also occurs in the Table Mountain pine-pitch pine (Pinus rigida) type, another fire-adapted community [42].
For fire regime information, search FEIS for this species by entering the species name on the Advanced Search page and selecting “Fire Regime” as the publication type.
Fire Management Considerations
Prescribed fire for hardwood control in southern pine stands results in the predominance of American beautyberry (Callicarpa americana) and sassafras. This predominance is a useful indicator of temporary control over other hardwoods that usually occupy later seres and are more serious competitors of pine. Prescribed fire at 8- to 12-year intervals can control sprout growth or new plant invasion [74].
In South Carolina, a prescribed January fire in loblolly pine increased sassafras browse quality and availability. Prior to the fire, sassafras stems were out of reach of white-tailed deer [21]. The protein content of sassafras leaves and twigs was highest in June following prescribed fire. By September, the protein content of all browse plants was similar on burned and unburned sites [23]. After logging and prescribed burning in an oak-pine stand in South Carolina, white-tailed deer browsed sassafras heavily [27].
Frequent prescribed fire can improve spring and summer forage quality in the southern pine forests, where sassafras often occurs.
Prescribed fire on utility rights-of-way does not control sassafras [5]. Vigorous root sprouting maintains sassafras even after repeated fires. Annual prescribed fire, however, may have a detrimental effect on sassafras fruit production [50]. On some sites, repeated annual fires may eventually eliminate sassafras [19,26,40].
A regression equation to calculate the relationship of sassafras bark thickness to stem diameter has been reported [46]. An equation for predicting standing sassafras dry weight (and therefore fuel loading) from sassafras basal diameter has also been reported [70].
Federal Status
No special status.
Other Status
Sassafras is listed under "Special Concern-Possibly Extirpated" in Maine [22].
Importance to Wildlife and Livestock
Sassafras leaves and twigs are consumed by white-tailed deer in both summer and winter. In some areas it is an important deer food [41]. Sassafras leaf browsers include woodchucks, marsh rabbits, and black bears [83]. Rabbits eat sassafras bark in winter [8]. Beavers will cut sassafras stems [15]. Sassafras fruits are eaten by many species of birds including northern bobwhites [58], eastern kingbirds, great crested flycatchers, phoebes, wild turkeys, catbirds, flickers, pileated woodpeckers, downy woodpeckers, thrushes, vireos, and mockingbirds. Some small mammals also consume sassafras fruits [16,65,75,83].
For most of the above mentioned animals, sassafras is not consumed in large enough quantities to be important. Carey and Gill [9] rate its value to wildlife as fair, their lowest rating.
Palatability and Nutritional Value
Palatability of sassafras to white-tailed deer is rated as good throughout its range [41].
The nutritional value of sassafras winter twigs is fair [67]. Seasonal changes in nutrient composition of sassafras leaves and twigs has been reported. Crude protein ranged from a high of 21.0 percent in April leaves to a low of 6.1 in January twigs [7].
Sassafras fruits are high in lipids and energy value [85].
Cover Value
No entry.
Value for Rehabilitation or Restoration of Disturbed Sites
Sassafras is used for restoring depleted soils in old fields [41].
Sassafras occurs on sites that have been largely denuded of other vegetation by the combination of frequent fire and toxic emissions from zinc smelters. Sassafras persistence on these sites is attributed to root sprouting; seedling reproduction is severely curtailed by the high level of toxins in the soil [52].
Other Uses
Sassafras oil is extracted from the root bark for use by the perfume industry, primarily for scenting soaps. It is also used as a flavoring agent and an antiseptic [41,83]. Large doses of the oil may be narcotic [83]. Root bark is also used to make tea, which in weak infusions is a pleasant beverage, but induces sweating in strong infusions. The leaves can be used to flavor and thicken soups [41,83]. The mucilaginous pith of the root is used in preparations to soothe eye irritations [83].
Because of its durability, sassafras was used for dugout canoes by Native Americans [49].
Sassafras wood is soft, brittle, light, and has limited commercial value [41]. It is durable, however, and is used for cooperage, buckets, fenceposts, rails, cabinets, interior finish, and furniture [24,41,83]. Carey and Gill [9] rate its value for firewood as good, their middle rating.
Other Management Considerations
Overstory removal often results in an increase in sassafras stems, particularly by sprouting [81]. Sassafras thickets may displace more desirable species for a short time, but few sassafras stems will occupy space in the overstory [62]. Some herbicides control sassafras [5]. Complete top-kill was achieved with injection of 2,4-D, picloram, and glyphosate, with no apparent sprouting 2 years after treatment [66]. Imidazolinone-based herbicide also controls sassafras [57]. Other herbicides do not control root sprouting [33,62].
Dense stands of sassafras are difficult to convert to pine or more desirable hardwoods [41]. Mowing is not effective in controlling sassafras; root sprouts quickly replace or increase aboveground stems [5].
Sassafras is difficult to transplant because of the sparse, far-ranging root system [75].
In North Carolina, mechanical removal of all non-desirable stems (intensive silvicultural cleaning) increased the amount of sassafras browse available to white-tailed deer. Prior to the cleaning, sassafras was out of reach of the deer; sprouts arising after the cleaning were within reach [18].
Major diseases of sassafras include leaf blight, leaf spot, Nectria canker and American mistletoe (Phoradendron flavescens) [41].
Insect pests of sassafras are mostly minor; the most damaging insects are the larvae of wood-boring weevils, gypsy moths, loopers, and Japanese beetles [41].
Sassafras is extremely sensitive to ozone [43].
Table A1— Forest and range ecosystems, Bureau of Land Management (BLM) physiographic regions, Kuchler plant associations, Society for American Foresters (SAF) forest cover types, and Society for Rangeland Management (SRM) rangeland cover types in which this species occurs.
Forest and Range Ecosystems (Garrison et al. 1977)
- FRES10 White - red - jack pine
- FRES12 Longleaf - slash pine
- FRES13 Loblolly - shortleaf pine
- FRES14 Oak - pine
- FRES15 Oak - hickory
- FRES16 Oak - gum - cypress
- FRES17 Elm - ash - cottonwood
- FRES18 Maple - beech - birch
- FRES19 Aspen - birch
BLM Physiographic Regions (Bernard and Brown 1977)
- No entry
Kuchler Plant Associations (Kuchler 1964)
- K083 Cedar glades
- K089 Black Belt
- K100 Oak - hickory forest
- K101 Elm - ash forest
- K104 Appalachian oak forest
- K106 Northern hardwoods
- K110 Northeastern oak - pine forest
- K111 Oak - hickory - pine forest
- K112 Southern mixed forest
SAF Cover Types (Eyre 1980)
- 14 Northern pin oak
- 15 Red pine
- 16 Aspen
- 20 White pine - northern red oak - red maple
- 21 Eastern white pine
- 40 Post oak - blackjack oak
- 43 Bear oak
- 44 Chestnut oak
- 45 Pitch pine
- 46 Eastern redcedar
- 50 Black locust
- 52 White oak - black oak - northern red oak
- 53 White oak
- 55 Northern red oak
- 57 Yellow-poplar
- 60 Beech - sugar maple
- 61 River birch - sycamore
- 64 Sassafras - persimmon
- 70 Longleaf pine
- 71 Longleaf pine - scrub oak
- 75 Shortleaf pine
- 76 Shortleaf pine - oak
- 78 Virginia pine - oak
- 79 Virginia pine
- 80 Loblolly pine - shortleaf pine
- 81 Loblolly pine
- 83 Longleaf pine - slash pine
- 84 Slash pine
- 85 Slash pine - hardwood
- 88 Willow oak - water oak - diamondleaf oak
- 108 Red maple
- 110 Black oak
SRM Rangeland Cover Types (Shiflet 1994)
- No entry
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