Index of Species Information

SPECIES:  Cercis canadensis


SPECIES: Cercis canadensis
AUTHORSHIP AND CITATION : Sullivan, Janet. 1994. Cercis canadensis. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].
ABBREVIATION : CERCAN SYNONYMS : C. reniformis Engl. [34] SCS PLANT CODE : CECA4 COMMON NAMES : eastern redbud redbud Judas-tree TAXONOMY : The currently accepted scientific name for eastern redbud is Cercis canadensis L. (Fabaceae) [11]. Texas redbud (C. c. var. texensis [Wats] Hopkins) is recognized by some authorities [34]. Others include Mexican redbud (C. c. var. mexicana [Rose] Hopkins) [41]. Clark and Bachtell [14] report, however, that a common opinion among nursery workers is that the two varieties represent environmentally induced morphologies (i.e. more leathery leaves in more xeric conditions) and that C. c. var. texensis and C. c. var. mexicana are all C. c. var. canadensis. Information is reported by variety in this write-up. LIFE FORM : Tree, Shrub FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


SPECIES: Cercis canadensis
GENERAL DISTRIBUTION : The range of eastern redbud extends from New Jersey and Pennsylvania west to southern Michigan and southeastern Nebraska; south to eastern Texas; and east to central Florida [34]. Its natural range appears to exclude the Gulf and Atlantic Coastal Plains [16]. It is extinct from one locality in extreme southern Ontario [34]. Texas redbud occurs from southern Oklahoma south to eastern, southern, and Trans-Pecos Texas; extreme southeastern New Mexico; and northern Mexico. In Mexico, its range extends from eastern Chihuahua and Coahila east to Tamps and south to San Luis Potosi and Hidalgo [34]. ECOSYSTEMS : 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 FRES32 Texas savanna FRES33 Southwestern shrubsteppe FRES38 Plains grasslands FRES39 Prairie STATES : AL AR DE FL GA IL IN KS KY LA MI MS MO NE NC NJ OH OK PA SC TN TX VA WV MEXICO BLM PHYSIOGRAPHIC REGIONS : 13 Rocky Mountain Piedmont 14 Great Plains KUCHLER PLANT ASSOCIATIONS : K082 Mosaic of K074 and K100 K084 Cross Timbers K089 Black Belt K099 Maple - basswood forest K100 Oak - hickory forest K101 Elm - ash forest K102 Beech - maple forest K103 Mixed mesophytic 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 : 25 Sugar maple - beech - yellow birch 26 Sugar maple - basswood 27 Sugar maple 40 Post oak - blackjack oak 42 Bur oak 44 Chestnut oak 46 Eastern redcedar 52 White oak - black oak - northern red oak 53 White oak 55 Northern red oak 59 Yellow-poplar - white oak - northern red oak 60 Beech - sugar maple 64 Sassafras - persimmon 65 Pin oak - sweetgum 78 Virginia pine - oak 79 Virginia pine 80 Loblolly pine - shortleaf pine 81 Loblolly pine 87 Sweetgum - yellow-poplar 89 Live oak 110 Black oak SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : Eastern redbud occurs in the open or as an understory tree common along the edge of woods in a variety of habitats [11,53]. In Kentucky, it occurs on exposed limestone cliffs in eastern redcedar (Juniperus virginiana) communities [12]. It very commonly occurs with flowering dogwood (Cornus florida) [54].


SPECIES: Cercis canadensis
WOOD PRODUCTS VALUE : The wood of eastern redbud is heavy, hard, and close-grained [11,16], but weak [56]. It is of no commercial value since the trees are rarely large enough to provide merchantable timber [11]. IMPORTANCE TO LIVESTOCK AND WILDLIFE : Eastern redbud seeds or pods are eaten by quail, pheasants [11], other birds including goldfinch [27], and deer [11]. Birds will open pods on the tree to get at the seeds [16]. Deer and cattle browse young trees [53]. Eastern redbud occurs in Ashe juniper (Juniperus ashei) habitat which is critical to endangered golden-cheeked warblers. The relationship of eastern redbud to golden-cheeked warblers was not reported (the warblers are primarily insectivorous) [32]. PALATABILITY : Armstrong [5] lists redbud as moderately preferred browse for white-tailed deer on the Edwards Plateau, Texas. NUTRITIONAL VALUE : Crude protein, digestibility, and water content were reported for eastern redbud on untreated plots and plots treated with herbicide and fire over the course of a growing season [8]. COVER VALUE : NO-ENTRY VALUE FOR REHABILITATION OF DISTURBED SITES : Eastern redbud was planted on surface mined sites in Indiana between 1928 and 1975 [10]. It is apparently no longer used much for this purpose. Eastern redbud was present as a volunteer at a density of 40 stems per acre on a 30-year-old plantation on a surface mined site in Missouri [57]. OTHER USES AND VALUES : Eastern redbud is a popular ornamental [11]. It is listed among trees useful for xeriscaping (landscaping for minimal water use) [40]. It is sometimes a valuable source of nectar for honey production [47]. The flowers may be pickled for use in salads or fried (a common practice in Mexico). An astringent fluid extract from redbud bark has been used in treating dysentery [41]. Eastern redbud is the state tree of Oklahoma [13]. OTHER MANAGEMENT CONSIDERATIONS : On southern red oak (Quercus falcata) sites that were clearcut, eastern redbud increased on plots where flowering dogwood, red maple (Acer rubrum), and hickory (Carya spp.) were injected with herbicides. This increase may be in part due to bird dispersed seed since bird activity was high in this area [26]. The response of eastern redbud to tebuthiruon or triclopyr treatments was reported by Stritzke and others [52]. Neither of the herbicides used resulted in more than 66 percent kill of eastern redbud, and by 2 years after the treatment, canopy cover of all species had increased to 94 percent (plots with no herbicides averaged 175% canopy cover) [52]. Picloram has been reported as effectively suppressing sprouting in redbud [58]. Eastern redbud is relatively free of serious insect pests and diseases [15]. It is fed upon by gypsy moth larvae (later stages) only when preferred species are not available [24]. Eastern redbud is rated as moderately sensitive to ozone damage [25].


SPECIES: Cercis canadensis
GENERAL BOTANICAL CHARACTERISTICS : Eastern redbud is a native, deciduous, small tree or shrub. Mature height ranges from 25 to 50 feet (7.6-15.2 m); the smaller figure is probably closer to average [15,16]. The crown is flat to rounded [53]. The trunk us usually straight, branching about 5 to 9 feet (1.5-2 m) above the ground [56]. The 0.5-inch- (1.2-cm) thick bark becomes scaly on older stems [11,16]. The root system of eastern redbud is long and coarse with a relatively small number of fine feeder roots near the surface [29]. The fruit is a flat, thin-walled legume (pod) 1.5 to 3.9 inches (4-10 cm) long and 0.32 to 0.72 inches (8-18 mm) broad, with several hard, shiny seeds [11]. The national champion (1976) eastern redbud from Springfield, Missouri, measured 47 feet tall (14.3 m), 8.17 inches (20.75 cm) in circumference, and had a crown spread 36 feet (10.9 m) in diameter [23]. Unlike most other members of the Fabaceae, eastern redbud does not form root nodules and does not appear to fix nitrogen [37]. RAUNKIAER LIFE FORM : Phanerophyte REGENERATION PROCESSES : Eastern redbud reproduces by bird dispersed seeds [47]. On average, first reproduction occurs when an individual is about 15 feet tall (4.5 m), although sometimes blooming begins when trees are 5 to 7 feet (1.5-2.1 m) in height [14]. Pods may be borne by 5-year-old eastern redbud, with a maximum reproductive age of 75 years. Good seed crops usually occur in alternate years [56]. The seeds exhibit combined dormancy: internal dormancy plus a hard, impermeable seedcoat [46]. In nursery practice, both scarification and cold, moist stratification are required for germination [59]. Eastern redbud sprouts from the roots or root crown following topkill [5]. Eastern redbud can be propagated by softwood cuttings [17]. SITE CHARACTERISTICS : Eastern redbud grows on almost any site that is not excessively wet, excessively dry, or strongly acidic [11,14,18]. Within its natural range, eastern redbud exhibits a strong preference for, and can be used as an indicator of, alkaline soils. Eastern redbud occurs in eastern redcedar communities on calcareous soils [12]. In Virginia, eastern redbud tends to occur on alkaline soils high in calcium and magnesium [20]. Collier and Longenecker [15] recommend a soil pH range of 6.0 to 8.0. Best growth of eastern redbud occurs on rich, moist soils, usually in partial shade [11]. It is usually not considered drought tolerant [18]; however, its ability to tolerate dry conditions is decreased in full full sun [14]. Probst [42] reported that eastern redbud is less common in oak forests on poor sites than in oak forests on good sites (defined by oak site indices). The upper elevational limit of eastern redbud is about 2,200 feet (670 m) in the southeastern portion of its range [18]. In Trans-Pecos Texas, eastern redbud ranges from 2,300 to 5,000 feet (701-1524 m) in elevation [41]. In Trans-Pecos Texas, Mexican redbud occurs in brushy arroyos, canyons, and limestone hillsides [41]. In the Konza Prairie of Kansas, eastern redbud occurs on rocky breaks in the grassland [45]. SUCCESSIONAL STATUS : Facultative Seral Species Eastern redbud is moderately tolerant of shade and grows well in full sun. Flower and fruit production is best in full sun, but eastern redbud's tolerance of full sunlight decreases in hot and dry areas [50,54]. It has been hypothesized that eastern redbud and similar midstory trees such as flowering dogwood attain a midstory canopy height that maximizes interception of sunflecks (transitory periods of full sun created by gaps in the canopy and the angle of the sun). If this is the case, eastern redbud requires at least short periods of sunlight for growth [54]. Eastern redbud apparently establishes in middle seres, forming a midstory layer, often with flowering dogwood. In North Carolina, eastern redbud and flowering dogwood developed as a distinct midstory under an oldfield shortleaf pine (Pinus echinata) canopy as the stand approached middle age (85 years) [7]. In western Tennessee, eastern redbud was recorded on 28-year-old abandoned agricultural fields, but not recorded on 3- and 12-year-old sites [48]. In Texas, primary succession in gravel pit excavations did not include eastern redbud even on the 47-year-old site, although eastern redbud was present in adjacent undisturbed forest [60]. Eastern redbud is a characteristic midstory species in mesic southern mixed hardwood forests which succeed pine-hardwood mixtures, and could therefore be classed as a late-successional species [43]. It occurs, for example, in an old-growth oak forest in northwestern Ohio [61] and it is present as seedlings, saplings and mature trees in southern mixed hardwood forest in north-central Florida [38]. It may not, however, be stable in some climax communities: eastern redbud was reported as decreasing in importance and relative dominance in an oldgrowth oak (Quercus spp.)-hickory (Carya spp.) forest in Illinois [49]. Although eastern redbud is not usually described as a pioneer species it often increases in dominance on sites experiencing disturbance. It is common on cutover or windthrown areas on calcareous soils [35]. In Indiana, a tornado caused severe windthrow in a sugar maple (Acer saccharum)-Ohio buckeye (Aesculus glabra) stand. Prior to the tornado, eastern redbud was a minor component in the stand. The most severely damaged portion of the forest was still mostly open 7 years after the disturbance and was dominated by sugar maple, elms (Ulmus spp.), Ohio buckeye, and eastern redbud. Eastern redbud, which increased dramatically in the first years after the tornado, will probably decline in importance as taller species begin to close the canopy [35]. SEASONAL DEVELOPMENT : Eastern redbud flowers appear before the leaves from as early as February in the southeastern United States to May [11,16,56]. In the southern part of its range, eastern redbud pods are fully grown by the end of May and ripen by September or October [16,56]. The pods split open in late autumn to winter, sometimes persisting on the tree through the winter [18,56].


SPECIES: Cercis canadensis
FIRE ECOLOGY OR ADAPTATIONS : Eastern redbud is rated as fire tolerant due to its habit of sprouting vigorously after top-kill by fire [5]. However, it is not reported as a postfire colonizer, and it is not a member of communities which experience frequent fire. At the prairie-forest ecotone, prairie fires limit the spread of woody vegetation. The lack of fire, perhaps coupled with climatic factors, has led to the encroachment of woodlands (in which eastern redbud occurs) onto former prairies [1,9]. In eastern Kansas, eastern redbud occurs in bur oak (Quercus macrocarpa)-chinkapin oak (Q. muehlenbergii) stands which have established on former tallgrass prairie (Andropogon-Panicum-Sorghastrum). These forests are normally confined to galleries along rivers. Hackberry (Celtis occidentalis) and eastern redbud establish about 10 to 30 years after the cessation of fire (and following oak establishment) in this area. Long fire-free periods allow succession to proceed from shade intolerant oaks to more shade tolerant hickories and eastern redbud. Eastern redbud may replace chinkapin oak on steep, dry sites. Hackberry is more likely to become dominant on moist sites [1]. In southern Illinois, a prairie barren was treated with four prescribed fires between 1969 and 1973 and subsequently experienced no fires. Eastern redbud seedlings and saplings were first recorded on the plots in 1983, 10 years after the last fire [3]. In central Oklahoma, eastern redbud occurred in post oak (Quercus stellata)-blackjack oak (Q. marilandica) forest which had not experienced recent fire, and was not reported for post oak-blackjack oak savanna which is maintained by fire and edaphic conditions [30]. 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 : Tree with adventitious-bud root crown/soboliferous species root sucker


SPECIES: Cercis canadensis
IMMEDIATE FIRE EFFECT ON PLANT : Eastern redbud is easily top-killed by fire but regenerates after fire by sprouting. Eastern redbud developed clusters of root sprouts after being top-killed by a prescribed spring fire to discourage the encroachment of woody species onto a south-central Ohio prairie [4]. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : In North Carolina, a 1931 wildfire burned with varying intensity in a 35-year-old oldfield loblolly pine (Pinus taeda) stand. Flowering dogwood and estern redbud were the most abundant woody species in the understory and in the shrub/seedling strata of the unburned area 9 years after the fire. Eastern redbud was recorded for the area that experienced crown fires but was present at a lower density and frequency than in the unburned stand. No eastern redbud was recorded for the area that had experienced surface fire. No specific data on composition of the plots prior to the fire was reported [39]. In Alabama, the relative dominance of eastern redbud decreased on plots that were burned in spring and in fall, as measured from 1 to 3 years after clearcutting and prescribed fire. By 3 years after a low-intensity spotty spring fire, however, average height of eastern redbud was 17 feet (5 m) (as compared to 21 feet (6) on unburned plots). On plots that had experienced a more uniform, intense fire, average height of eastern redbud was 8 feet (2.4 m) only 1 year after the fire [28,36]. Germinable eastern redbud seeds were present in the seedbank but not represented in the vegetation of a tallgrass prairie site that was prescribed burned annually between 1978 and 1984. The seeds were not reported from unburned sites or from sites that experienced fire at 4-year intervals [2]. Average crude protein for eastern redbud was slightly higher on plots that had been treated with herbicide and fire than on untreated plots [8]. The Research Paper by Bowles and others 2007 provides information on postfire responses of several plant species, including eastern redbud, that was not available when this species review was written. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : NO-ENTRY FIRE MANAGEMENT CONSIDERATIONS : In Texas, chaining and burning live oak (Quercus virginiana), white oak (Q. alba), Texas oak (Q. texana), and Ashe juniper (Juniperus ashei) resulted in an increase in fire climax species, including Texas redbud. Fires maintain root sprouters like Texas redbud in a low growing condition. Prescribed fire is recommended for these areas to cover approximately 10 to 15 percent of the total area each year (resulting in a 5- to 10-year rotation) [21].


SPECIES: Cercis canadensis
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