Index of Species Information

SPECIES:  Carya ovata


SPECIES: Carya ovata
AUTHORSHIP AND CITATION : Tirmenstein, D. A. 1991. Carya ovata. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].
ABBREVIATION : CAROVA SYNONYMS : Hicoria ovata (P. Mill.) Britt. SCS PLANT CODE : CAOV2 COMMON NAMES : shagbark hickory shellbark hickory scalybark hickory TAXONOMY : The currently accepted scientific name of shagbark hickory is Carya ovata (P. Mill.) K. Koch [30]. It is a member of the walnut family, Juglandaceae [23]. Two varieties are commonly recognized [30]: Carya ovata var. ovata (Miller) K. Koch Carya ovata var. australis (Ashe) Little At least five other varieties, including C. o. var. fraxinifilia Sarg., C. o. var. nuttallii Sarg., and C. o. var. pubescens, were formerly recognized by many authorities [23,50,57]. However, although occasionally encountered in the literature, they are no longer recognized by most taxonomists. Shagbark hickory hybridizes naturally with butternut hickory (C. cordiformis), pecan (C. illinoensis), and shellbark hickory (C. laciniosa) [24,36]. Common hybrid products and their derivatives follow [57]: Dunbar hickory C. X dunbarii (C. laciniosa x C. ovata) Laney hickory C. X laneyi Sarg. (C. cordiformis x C. ovata) Horticultural hybrids between shagbark hickory and butternut hickory, pecan, shellbark hickory, and mockernut hickory (C. tomentosa) have also been reported [57]. LIFE FORM : Tree FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


SPECIES: Carya ovata
GENERAL DISTRIBUTION : Shagbark hickory occurs throughout most of the eastern North America but is largely absent from the southeastern and Gulf coastal plains and the lower Mississippi Delta. It is found from southeastern Nebraska and southeastern Minnesota eastward through southern Ontario and Quebec to Maine and extends southward to Georgia, Alabama, Mississippi, Louisiana, and eastern Texas [23]. Disjunct populations have been reported in the mountains of northeastern Mexico [23,36]. The variety ovata encompasses most of the species' range and grows westward to southeastern Missouri and eastward to Louisiana. The variety australis occurs in southeastern North America [36]. ECOSYSTEMS : FRES10 White - red - jack pine FRES13 Loblolly - shortleaf pine FRES14 Oak - pine FRES15 Oak - hickory FRES16 Oak - gum - cypress FRES18 Maple - beech - birch STATES : AL AR CT DE GA IL IN IA KS KY LA ME MD MA MI MN MS MO NE NH NJ NY NC OR OK PA RI SC TN TX VT VA WV WI ON PQ MEXICO BLM PHYSIOGRAPHIC REGIONS : NO-ENTRY KUCHLER PLANT ASSOCIATIONS : K081 Oak savanna K089 Black Belt K100 Oak - hickory forest K102 Beech - maple forest K103 Mixed mesophytic forest K111 Oak - hickory pine forest SAF COVER TYPES : 21 Eastern white pine 42 Bur oak 43 Bear oak 44 Chestnut oak 45 Pitch pine 51 White pine - chestnut oak 52 White oak - black oak - norther red oak 53 White oak 57 Yellow poplar 59 Yellow poplar - white oak - northern red oak 60 Beech - sugar maple 64 Sassafras - persimmon 65 Pin oak - sweet gum 75 Shortleaf pine 76 Shortleaf pine - oak 78 Virginia pine - oak 80 Loblolly pine - shortleaf pine 81 Loblolly pine 82 Loblolly pine - hardwood 87 Sweet gum - yellow poplar 91 Swamp chestnut oak - cherrybark oak SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : In certain floodplain communities, shagbark hickory grows as a codominant with black oak (Quercus velutinus), green ash (Fraxinus pennsylvanica), and northern red oak (Quercus rubra). Shagbark hickory is included as a codominant or indicator in the following community type (cts) and plant association (pas) classifications: Area Classification Authority IL general veg., cts Thomson and Anderson 1976 NE general veg., cts Aikman 1926 NE, KS general veg., cts Weaver 1960 NE, KS general veg., cts Weaver and Albertson 1945 OH general veg., cts Hamilton and Limbird 1982 sw OH general veg., pas Braun 1936


SPECIES: Carya ovata
WOOD PRODUCTS VALUE : The wood of shagbark hickory is tough, heavy, hard, and resilient [23,54]. It is well suited to uses which require a wood capable of resisting impact and stress [23]. The close-grained heartwood is reddish brown and the sapwood nearly white [29,57]. Wood was formerly used to make wheels and spokes for wagons, carriages, carts, and early automobiles [29]. Shagbark hickory wood is currently used to make furniture, flooring, tool handles, dowels, ladders, and sporting goods [29,43]. Shagbark hickory is an excellent fuelwood. It has high heat value and burns evenly with a long-lasting steady heat. The wood imparts a hickory-smoked flavor to foods and is often used to make charcoal [23]. IMPORTANCE TO LIVESTOCK AND WILDLIFE : Browse: Shagbark hickory is seldom browsed by deer unless preferred foods are limited or unavailable [23]. It is browsed by livestock only when other food is scarce. Nuts: Shagbark hickory nuts are readily eaten by a wide variety of birds and mammals. The black bear, red fox, gray fox, white-footed mouse, eastern chipmunk, and rabbits eagerly feed on the nuts [23]. They are a preferred food of the fox squirrel during August, September, October, February, and March [52], and in some areas, hickory nuts comprise 5 to 10 percent of the eastern chipmunk's diet [23]. Black bears consume large quantities of hickory nuts during the fall in parts of New England. The abundance of mast crops such as acorns and hickory nuts can affect black bear reproductive success during the following year [18]. Many birds, including the mallard, wood duck, northern bobwhite, and wild turkey, feed on shagbark hickory nuts [23]. The ring-necked pheasant, common crow, bluejay, white-breasted nuthatch, red-bellied woodpecker, and yellow-bellied sapsucker also consume hickory nuts [41]. PALATABILITY : Shagbark nuts are highly palatable to many birds and mammals. Hickory nuts are rated as having fair value for upland game birds and songbirds and good value for fur and game mammals [13]. Hickory browse appears to be low of low palatability to most big game species and to all classes of domestic livestock [23]. NUTRITIONAL VALUE : Browse: The nutrient content of shagbark hickory browse varies seasonally. Loomis [39] reported an average fall ash content of 8.1 percent and a spring ash content of 9.6 percent. Nuts: Shagbark hickory nuts are high in protein, fats, and carbohydrates [58]. Caloric content is as follows [52]: plant cal./g dry wt. cal./nut kernel 6,570 6,700 shell 4,240 8,600 husk 4,150 16,100 COVER VALUE : Shagbark hickory presumably provides cover for a variety of birds and mammals and are probably used as den trees by squirrels [11]. VALUE FOR REHABILITATION OF DISTURBED SITES : Shagbark hickory may have potential for use on many types of disturbed sites. It naturally recolonizes strip mines in Maryland and West Virginia [25], and lead pit mines with high levels of lead and zinc in the soil [6]. Strains obtained from floodplain habitats are particularly well adapted to streambank plantings [14]. Shagbark hickory can be readily propagated from seed. Cleaned seed averages 100 per pound (221/kg) [57]. Seed may be planted during the fall, or stratified and planted in the spring [7]. Mulching generally improves the results of fall plantings. OTHER USES AND VALUES : Shagbark hickory nuts are sweet and edible [54]. They were once a staple food of some Native American peoples [34] and today are the important hickory nut of commerce [57]. Shagbark hickory was first cultivated in 1911 [7], and many cultivars are now available [57]. At least one ornamental cultivar has been developed, but it has not been widely planted. Shagbark hickory is an important shade tree in some residential areas and is well suited for planting as a specimen tree in landscaping [23]. OTHER MANAGEMENT CONSIDERATIONS : Insects/diseases: Shagbark hickory is susceptible to numerous insects and diseases [23]. Damage can be serious, particularly during drought years. Mechanical treatment: Hickories (Carya spp.) commonly produce epicormic branches or water sprouts after pruning [12]. Wildlife considerations: In New England, black bears are most likely to damage crops in poor mast (acorn and hickory nut) years [18]. Silviculture: Shagbark hickory is long-lived and slow-growing. Consequently, it does not respond well to even-aged management systems if rotations are less than 100 years. It does respond well to release and is reportedly favored by management for long rotations (200 years or more) [23]. Following timber harvest, most hickory stems develop from advance regeneration. Some advance regeneration may be damaged during logging operations, but plants typically sprout and many quickly overtop older residual stems [49]. New sprouts are characterized by a straight bole and rapid growth and are considered the most desirable hickory regeneration in new stands. Derivation of hickory regeneration following various types of timber harvest was documented as follows in an Indiana oak-hickory stand [49]: clearcut shelterwood med. partial (percent of total reproduction) new seedlings 2 2 2 adv. regeneration 30 77 73 new sprouts 56 21 24 stump sprouts 12 0 1


SPECIES: Carya ovata
GENERAL BOTANICAL CHARACTERISTICS : Shagbark hickory is a medium to large deciduous tree which commonly grows to 60 or 80 feet (20-25 m) in height and up 20 inches (51 cm) in diameter [21,29]. On favorable sites, trees may grow to 131 feet (40 m) or more in height and reach up to 9 feet 8 inches (295 cm) in diameter [57]. Open-grown plants are characterized by an oblong crown, whereas those growing in forested areas tend to have a straight, slender columnar crown [29]. The shaggy gray bark exfoliates in long platelike strips [2,24,57]. Shagbark hickory has a deep taproot [29]. Shagbark hickory is monoecious [54]. Staminate flowers are borne on long-stalked catkins at the tip of old wood or in the axils of the previous season's leaves [23,24,54]. Pistillate flowers occur in short terminal spikes [23,54]. The fruit is a smooth, globose or subglobose nut [46]. Nuts are borne singly or in clusters of two or three [24]. RAUNKIAER LIFE FORM : Phanerophyte REGENERATION PROCESSES : Shagbark hickory regenrates through seed and by vegettaive means. Seed: Shagbark hickory begins producing seed at approximately 40 years of age. Optimum seed production occurs between 60 and 200 years of age; maximum age of seed production is approximately 300 years [57]. Good crops occur at 1- to 3-year intervals, with little or no seed production in intervening years [23]. During favorable years, some trees can produce 1.5 to 2 bushels (53-70 L) of nuts [7]. Tree (stem) diameter and crown size apparently serve as the best indicators of seed production [23]. Seed is dispersed by gravity and by birds and mammals [23,61]. Squirrels and chipmunks are typically much more important as dispersal agents than birds are. The now-extinct passenger pigeon dispersed seeds of many species of hickory [61]. During poor seed years, seed predation by birds, mammals, and insects can eliminate most of the seed crop [23]. Hickory seeds exhibit embryo dormancy that can be broken by stratification at 37 degrees F (3 deg C) for 90 to 120 days [23]. Germination of fresh seed ranges from 50 to 75 percent. Vegetative regeneration: Shagbark hickory typically sprouts prolifically after plants are cut or damaged by fire [23]. Trees with diameters up to 8 to 10 inches (20-24 cm) typically sprout from the stump. As diameter increases stump-sprouting declines, but "root-suckering" increases. Young sprouts generally compete well in newly regenerated stands, but after 10 to 20 years, the rate of sprout growth declines and shagbark hickory may be outcompeted by faster growing associates [23]. SITE CHARACTERISTICS : Shagbark hickory is most commonly associated with upland slopes in the North, and with river bottoms and coves in the South [23]. It also grows on the lower slopes of wooded bluffs, in ravines, valleys, and at the edges of swamps [21,29]. Shagbark hickory generally occurs as scattered individuals or in small groups but rarely forms pure stands [2,51]. Plant associates: Shagbark hickory occurs as a principal dominant in drier parts of the upper Midwest with oaks (Quercus spp.) and other hickories. [59]. It also grows as aminor component in bur oak (Q. macrocarpa), chestnut osk (Q. prinus), white oak (Q. alba)-black oak-northern red oak, pine (Pinus spp.)-oak-sweetgum (Liquidambar styraciflua),loblolly pine (Pinus taeda)-hardwood, and swamp chestnut oak (Quercus prinoides)-cherrybark oak (Q. falcata var. pagodaefolia) [23]. Many oaks, including white oak, northern red oak, black oak, northern pin oak (Quercus ellipsoidalis), southern red oak (Q. falcata), chinkapin oak (Q. muehlenbergii), bur oak, and other hickories are generally prominent overstory associates [1,23,59]. Red maple (Acer rubrum), sugar maple (A. saccharum), hophornbeam (Ostrya virginiana), shortleaf pine (Pinus echinata), American basswood (Tilia americana), redbud (Cercis canadensis), and sourgum (Nyssa sylvatica) also commonly occur with shagbark hickory [2,48]. Understory associates are numerous and varied throughout the species' range. Raspberries and blackberries (Rubus spp.), blueberries and huckleberries (Vaccinium spp.), rhododendron (Rhododendron spp.), serviceberry (Amelanchier spp.), gooseberries (Ribes spp.), hawthorn (Crataegus spp.), hazel (Corylus cornuta), muscadine grape (Vitis rotundifolia), common greenbrier (Smilax rotundifolia), western snowberry (Symphoricarpos occidentalis), common witch-hazel (Hamamelis virginiana), wild ginger (Asarum caudatum), nettle (Urtica spp.), and Canada beadruby (Maianthemum canadense) are important understory components in many areas [2,3,9]. Climate: Shagbark hickory grows across a wide range of climatic conditions but grows best in a humid climate. It can survive temperature extremes of -40 degrees F (-40 deg C) and 115 degrees F (46 deg C). Growing season length varies from 140 days in the North to 260 days in the South [23]. Soils: Shagbark hickory reaches greatest abundance on deep, rich, moist soils [29,42]. It occurs on soils derived from a variety of sedimentary and metamorphic parent materials and grows across a wide range of soil fertility conditions [23]. It appears to be tolerant of soils with high concentrations of lead and zinc [6]. In Arkansas, it is common on clayey soils derived from Mississippian and Pennsylvanian shales [23]. Elevation: Shagbark hickory generally occurs at high elevations in much of the North [42]. It typically occurs below 3,000 feet (910 m) in the foothills of West Virginia [15]. In the Blue Ridge Mountains of North and South Carolina, it occurs up to 3,000 feet (910 m) and in northern Arkansas at elevtions below 2,000 feet (610 m) [23]. SUCCESSIONAL STATUS : Shagbark hickory is slow growing and intermediate in shade tolerance. Saplings can persist for many years beneath a forest canopy and respond rapidly when released. It grows as a climax species in most oak-hickory forests [23]. It is a prominenent late seral or climax species in old-growth oak stands in Indiana where it replaces early to mid seral species such as honey locust (Gleditsia triacanthos), black walnut (Juglans nigra), and oak [45]. It replaces bur oak, black cherry (Prunus serotina), and white oak in bur oak-chinkapin oak-black oak forests of Wisconsin and northeastern Kansas [1,16]. It may ultimately be replaced by more shade-toleant species such as sugar maple, American basswood, and hophornbeam [1,16]. At the western edge of its range, shagbark hickory has invaded the prairie [32], but heavy-seeded species such as shagbark hickory are generally slow to invade new areas [22]. Shagbark hickory has invaded oldfield communities, but seedlings are rarely observed more than 100 feet (30 m) from the forest margin [11]. In parts of east-central Indiana and elsewhere, it often establishes in gaps created by dead elms (Ulmus spp.) [44]. SEASONAL DEVELOPMENT : Shagbark hickory flowers in late March at the southwestern edge of its range and as late as early June in the North and Northeast [23]. Flowers open when the leaves are nearly full grown [23]. Fruit ripens in September and October and splits into four pieces [34]. Seed is dispersed from September thrugh December. Generalized flowering and fruiting dates by geographic location are: Location Flowering Fruiting Authority New England May 29-June 28 ---- Seymour 1985 n-c Plains April-May Sept.-Oct. Stephens 1973 Great Plains April-May ---- Great Plains Flora Assoc. 1986 se U.S. May ---- Duncan & Duncan 1988 sw U.S. March-June Sept.-Cot. Vines 1960 NC, SC May October Radford & others 1968


SPECIES: Carya ovata
FIRE ECOLOGY OR ADAPTATIONS : Periodic fires tend to favor oak over over the less fire-resistant hickory. The slow-growing, thin-barked shagbark hickory is reduced by short fire intervals [33]. Frequent burning at prairie margins reduces or eliminates shagbark hickory seedlings [33]. Fire suppression in parts of the Northeast has reduced fire frequency and converted oak-hickory forests to more mesophytic stands [60]. However, in an oak-hickory forest in Indiana, fire suppression since 1917 has contributed to the recruitment of shagbark hickory, sugar maple, white ash (Fraxinus americana), and American elm (Ulmus americana) [45]. Increases in tree density in oak-hickory forests in Michigan have also been attributed to fire suppression [10]. In the Great Smoky Mountains, fire suppression since 1940 has allowed hickories to reach fire-resistant size [28]. Shagbark hickory usually sprouts from the root crown or stembase after abovegrund foliage is killed by fire. Seedling establishement may also occur. FIRE REGIMES : Find fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find Fire Regimes". POSTFIRE REGENERATION STRATEGY : survivor species; on-site surviving root crown or caudex off-site colonizer; seed carried by animals or water; postfire yr 1&2


SPECIES: Carya ovata
IMMEDIATE FIRE EFFECT ON PLANT : All sizes of shagbark hickory are susceptible to damage by fire [20]. However, trees less than 10 inches [25 cm] in d.b.h. tend to be more susecptible to damage or mortality than trees larger than 10 inches d.b.h. [53,60] The effect of fire on hickories varies with topography, slope, aspect, season of burn, and fire intensity [37]. Light fires commonly top-kill sprouts and seedlings but leave underground portions undamaged [23]. Hot fires often kill or damage even large trees [23]. Trees are generally less severely damaged if burned while dormant [37]. The tight, solid bark of hickories is more susceptible to fire-scarring than is the rough or corky bark of other species [31]. Fire-scarred hickories are susceptible to rot [23,42], which can ultimately kill the tree. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : In an oak-hickory stand in southeastern Missouri, most hickories were top-killed by a wildlfire [38]. Fire-caused mortality of shagbark hickory can be predicted using a mathematical model [39]. PLANT RESPONSE TO FIRE : Mature hickories often sprout from the root crown when top-killed by fire [38]; top-killed seedlings sometimes sprout from dormant buds located on the root collar or lower portions of the stem [49]. Some seedling establishment may also occur. Postfire increases in stem density have been reported, but recovery is often relatively slow. Fifty-five years after a late summer fire in Connecticut, hickories exhibited greater "relative and absolute levels" than on adjacent unburned sites [60]. The Research Paper by Bowles and others 2007 provides information on postfire responses of several plant species, including shagbark hickory, that was not available when this species review was written. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : Postfire origin of hickory ingrowth following a late summer fire in a Connecticut mixed hardwood stand was 105 sprouts and 162 seedlings per hectare in burned areas, compared to four sprouts and nine seedlings per hectare in unburned areas. Hickories of sprout origin represented 31 percent of stems of all species on unburned plots and 39 percent on burned sites [60]. FIRE MANAGEMENT CONSIDERATIONS : Scattered surviving hickories often develop large crowns and exhibit good nut production after fire. These trees may be particularly valuable for many wildlife species.


SPECIES: Carya ovata
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