Index of Species Information

SPECIES:  Sapindus saponaria var. drummondii


SPECIES: Sapindus saponaria var. drummondii
AUTHORSHIP AND CITATION : Tirmenstein, D. A. 1990. Sapindus saponaria var. drummondii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].
ABBREVIATION : SAPSAPD SAPSAP SYNONYMS : Sapindus saponaria Sapindus drummondii Sapindus marginatus SCS PLANT CODE : SASAD COMMON NAMES : western soapberry soapberry Chinaberry wild chinaberry soap berry wild chinatree Indian soap plant jaboncillo Mexican soapberry wild China-tree Drummond soapberry cherioni cherrion TAXONOMY : Several taxonomic treatments have been proposed for western soapberry. Some authorities consider western soapberry and wingleaf soapberry to be discrete species (Sapindus drummondii and S. saponaria, respectively) [21,23,41]. However, many others now regard these entities as varieties of a single species (Sapindus saponaria) [10,17,26,33]. Still other taxonomists recognize only a single, although highly variable, species (Sapindus saponaria L.) [13]. The currently preferred scientific name of western soapberry is Sapindus saponaria var. drummondii (Hook and Arn.) L. Benson [10,14,26]. Western soapberry is a member of the primarily tropical family Sapindaceae, which comprises nearly 1,000 species [31,34]. Western soapberry differs from the closely related wingleaf soapberry (Sapindus saponaria var. saponaria) in various morphological characteristics and in geographical distribution [17]. LIFE FORM : Tree, Shrub FEDERAL LEGAL STATUS : See OTHER STATUS OTHER STATUS : Western soapberry has been placed on the Colorado Natural Area List of Concern [31].


SPECIES: Sapindus saponaria var. drummondii
GENERAL DISTRIBUTION : Western soapberry grows from southwestern Missouri to southeastern Colorado, southward to Arizona and eastward to Texas, Louisiana, and northern Mexico [21]. It is described as a Madro-Tertiary genus which was largely restricted to relatively moist riparian habitats as conditions became increasingly hot and dry during the late Pleistocene [36]. ECOSYSTEMS : FRES15 Oak - hickory FRES16 Oak - gum - cypress FRES28 Western hardwoods FRES30 Desert shrub FRES32 Texas savanna FRES33 Southwestern shrubsteppe FRES40 Desert grasslands STATES : AZ AR CO KS LA MO NM OK TX MEXICO BLM PHYSIOGRAPHIC REGIONS : 7 Lower Basin and Range 13 Rocky Mountain Piedmont 14 Great Plains KUCHLER PLANT ASSOCIATIONS : K027 Mesquite bosques K059 Trans-Pecos shrub savanna K060 Mesquite savanna K062 Mesquite - live oak savanna K081 Oak savanna K084 Cross Timbers K087 Mesquite - oak savanna K113 Southern floodplain forest SAF COVER TYPES : 68 Mesquite 235 Cottonwood - willow 240 Arizona cypress 241 Western live oak 242 Mesquite SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : Western soapberry grows as a dominant or codominant in a number of Southwestern riparian communities. Common codominants include Arizona black walnut (Juglans major), Mexican ash (Fraxinus berlandieriana), cedar elm (Ulmus crassifolia), and pigeon-berry (Rivina humilis). It is listed as a dominant or indicator in the following community type (cts) classifications: Area Classification Authority AZ,NM riparian cts Szaro and Patton 1986 Southwest riparian cts Szaro 1990a Southwest riparian cts Szaro 1990b TX: Santa Ana Nat'l. general veg. cts Vora 1990a Refuge sw NM riparian cts Medina 1986


SPECIES: Sapindus saponaria var. drummondii
WOOD PRODUCTS VALUE : Wood of western soapberry is light brown or yellowish with lighter sapwood [33,41]. The wood is hard, strong, close-grained, and heavy [29,41]. It averages 51 pounds per cubic foot [41]. Western soapberry wood splits easily into thin strips which can be used to make frames, boxes, and baskets [16,29,41]. Wood formerly received local use for cotton baskets, crates, pack saddles, and fuel [7,34]. In some areas it is still used as firewood [41]. Although western soapberry wood "finishes nicely," it has little or no commercial value [19,41]. IMPORTANCE TO LIVESTOCK AND WILDLIFE : Western soapberry browse contains poisonous saponins and is rarely eaten by domestic livestock [40]. It occasionally receives slight cattle use where other forage is scarce or unavailable [7,14]. Berries are not eaten by livestock [37]. PALATABILITY : Western soapberry foliage is apparently of low palatability to domestic livestock. Mature leaves are unpalatable to foraging ants [45]. Berries contain poisonous saponins which render them objectionable in taste [37]. NUTRITIONAL VALUE : NO-ENTRY COVER VALUE : Western soapberry provides hiding or resting cover for a variety of game species [19]. It also furnishes nesting sites for doves and many songbirds [19]. VALUE FOR REHABILITATION OF DISTURBED SITES : Western soapberry has been widely planted in shelterbelts throughout the southern Great Plains [29]. Its ability to persist on dry, windy, infertile sites suggests potential value for use on some disturbed sites. Plants may be propagated through seed or stem cuttings [16,34]. Approximately 100 pounds (45 kg) of fruit yields 30 to 35 pounds (14-16 kg) of cleaned seed [29]. Fruit can be collected during late fall or winter [47]. Properly pretreated seed can be planted in the spring at a depth of 0.75 inch (19 mm) [41]. Detailed information is available on seed collection, storage, and planting techniques [23,29,42]. Western soapberry can also be propagated through hardwood or softwood cuttings [34,41]. Cuttings often root poorly, but the use of auxins can effectively stimulate root formation [16]. Cuttings taken in May, June, or July can root in 5 to 6 weeks if properly treated [34]. Success depends largely on climate, the genetic stock used, and the season in which cuttings are obtained [16]. Vegetative propagation has been examined in detail [16]. OTHER USES AND VALUES : Western soapberry is attractive and tolerant of poor soil and harsh urban growing conditions [29,34]. Consequently, it is well suited for use as a shade tree or ornamental in landscape plantings. It has been cultivated since 1900 [23,41]. Western soapberry casts light shade and makes a good patio tree [34]. Its attractive, persistent fruit and unique bark make it visually appealing during the winter [34]. It is extremely wind resistant and hardy to zone 5 [34]. Berries contain approximately 37 percent saponin and were crushed to make cleaners and soaps by Native American peoples and early settlers [7,32]. Western soapberry can, however, cause contact dermatitis in susceptible people [14]. Although the berries are somewhat poisonous, preparations made from them have been used to treat fevers, rheumatism, and kidney problems [26,41]. The closely related wingleaf soapberry (Sapindus saponaria var. saponaria) has been widely used in parts of the Old World to treat ulcers, joint pain, epilepsy, cataracts, bronchial asthma, and "uterus pain" [44]. It has reportedly produced good results in the treatment of psoriasis, jaundice, and pellagra [44]. The inner bark of western soapberry has been used in home remedies as an astringent [17]. Seeds of western soapberry have been used to make buttons and necklaces [41]. OTHER MANAGEMENT CONSIDERATIONS : Many unique bottomland communities of south-central Oklahoma, in which western soapberry occurs as a prominent species, are being threatened by agro- industrial activities [25]. Experts estimate that if present trends continue, these communities will soon be completely eliminated [25].


SPECIES: Sapindus saponaria var. drummondii
GENERAL BOTANICAL CHARACTERISTICS : Western soapberry is a small to medium-sized deciduous tree which reaches 20 to 50 feet (6-15 m) in height [7,16]. Crown spread can reach 25 to 30 feet (7-9 m) [16], and trunk diameter can reach 1 to 2 feet (0.3-0.6 m) [41]. Branches are commonly erect and form a rounded crown [41]. Twigs are brittle, moderately stout, yellowish-gray to gray-brown and pubescent to glabrous [27,33,41]. The thin bark is split by deep fissures into long narrow plates [17,34]. Bark is grayish to reddish-brown and scaly [15,17]. Western soapberry is described as moderately slow growing [16]. The alternate leaves are pinnately compound [33]. The 4 to 10 pairs of leaflets are oblong to elliptic-lanceolate and entire and 1.5 to 3.2 inches (4-9 cm) in length [10,17,33,34]. Leaflets are glossy-green and glabrous above and soft pubescent or glabrous beneath [16,41]. Leaves turn a yellow-gold in fall [34]. Western soapberry is dioecious [33]. Small, yellowish-white flowers are borne in large terminal or axillary panicles on new growth [16,29,33]. Panicles are 5 to 10 inches (13-25 cm) in length [41]. Fruit is a fleshy, translucent yellow-orange drupe [16,29,33]. The leathery-skinned drupes are somewhat wrinkled and are borne in clusters of 10 to 30 [17,33]. Fruit is persistent but shrivels and blackens by spring [34]. Each drupe averages 0.5 inch (2.5 cm) in diameter [34] and generally contains a single seed, although drupes may sometimes contain as many as two or three seeds [16,41]. Obovoid seeds are dark brown or black and semiglossy [16,33]. Seeds have a hard seed coat, and although the surface appears smooth, it is minutely pitted [10,16]. RAUNKIAER LIFE FORM : Phanerophyte REGENERATION PROCESSES : Seed: Western soapberry produces an abundance of seed annually [29]. Seed soundness averages approximately 77 percent [41]. Seedcoat structure and seed response to pregermination treatments vary greatly [29]. Germination: Germination of western soapberry is often difficult because of embryo dormancy and an impermeable seed coat [29]. In laboratory tests at alternating day (86 degrees F [30 degrees C]) and night (68 degrees F [20 degrees C]) temperatures, germination capacity of western soapberry ranged from 7 to 68 percent [29]. Germination can generally be improved by soaking seeds in sulfuric acid for 2 hours or more, and then stratifying seeds in moist sand at 35 to 45 degrees F (2-7 degrees C) for 90 days [29,47]. Vora [42] reported increased germination after acid soaks of 45 minutes or more; greatest germination (71 percent) occurred after acid soaks of 120 minutes. However, Munson [23] observed better germination after soaking seeds in acid for 60 to 90 minutes than after soaking for either 30 or 120 minutes. In general, stratification can increase germination by up to 25 percent [23]. In some instances, freshly collected seed may germinate well without pretreatment [23,29]. Generally, if seeds absorb water after 5 to 7 days of soaking, they can be planted without further treatment [29]. However, if seeds remain small and hard, they should be scarified and stratified prior to planting [29]. Dried fruit can be stratified at 70 to 85 decrees F (21-29 degrees C) for 6 to 10 weeks followed by low temperature stratification for 90 days [29]. Germination of western soapberry has been examined in detail [23,29,42]. Seedling establishment: Initial top growth of seedlings is typically slow [29]. Early height growth has been reported as follows [42]: height (cm) ---------------------- 5 10 25 date planted (days after emergence) June 1986 - - 80 Vegetative response: Western soapberry reportedly spreads by underground rhizomes [32]. However, little is known about vegetative regeneration of this species. SITE CHARACTERISTICS : Western soapberry grows along rivers and canyon sides, and in desert washes, arroyos, and dry watercourses [7,16,19,26]. It also grows singly or in thickets in foothills and uplands, at the margins of woods, and in pasture ravines on waste ground [10,19,33]. Western soapberry is a common component of upper desert scrub, desert and semidesert grasslands, tropical and subtropical scrublands, and oak-woodland communities [4,5,16,24]. It is particularly well represented in many riparian woodland communities. Plant associates: Common associates in Arizona gallery or canyon forests near streamcourses include netleaf hackberry (Celtis reticulata), Texas mulberry (Morus microphylla), Goodding willow (Salix gooddingii), velvet ash (Fraxinus velutina), Arizona sycamore (Platanus wrightii), burrowbrush (Hymenoclea spp.), seepwillow (Baccharis glutinosa), walnut (Juglans spp.), skunkbush sumac (Rhus trilobata), and Atlantic poison-oak (Toxicodendron toxicarium) [11,48]. Netleaf hackberry, American elm (Ulmus americana), boxelder (Acer negundo), indian-currant coralberry (Symphoricarpos orbiculatus), post oak (Quercus stellata), and blackjack oak (Q. marilandica) occur with western soapberry in bottomland forests of south-central and southwestern Oklahoma [8,25]. On floodplain bottoms and river terrace communities of Texas, pecan (Carya illinoensis), live oak (Quercus virginiana), hackberry (Celtis spp.), Mexican ash, cedar elm, Texas persimmon (Diospyros texana), and honey mesquite (Prosopis glandulosa) are often well represented [43,46]. Soils: Western soapberry commonly grows on highly calcareous or clayey soils [23,29]. It occurs on heavy clay, silty clay, and other soil types [43]. Western soapberry is highly tolerant of soils with limited moisture [16,34] and grows well on dry, well drained sites [40]. However, it also thrives on many moist soils [37]. Plants grow well on infertile soils [16,34]. Western soapberry occurs on soils derived from a variety of parent materials including sandstone, but it is most often associated with limestone soils [32]. Climate: Western soapberry is tolerant of low to high humidity and rainfall [32]. It grows naturally in subhumid to semiarid mesothermal climates [39]. On the Edwards Plateau of southern Texas, annual precipitation can range from 16 to 33 inches (38-84 cm) [39]. Elevation: Generalized elevational range by geographic location is as follows [3,14,26]: location elevation AZ 2,500 to 6,000 feet (762-1,829 m) Trans-Pecos, TX 1,100 to 6,500 feet (335-1,981 m) SUCCESSIONAL STATUS : Western soapberry is a prominent member of mature bottomland forests of south-central Oklahoma [25]. These climax stands can persist for hundreds of years and are characterized by an extensive colonization period [25]. In floodplain bottomlands of south Texas, species such as retama (Cercidium spp.), dry-land willow (Baccharis neglecta), huisache (Acacia smallii), and Texas prickly pear (Opuntia lindheimeri) dominate earliest successional stages [43]. Common overstory species in subsequent successional stages include retama, sugarberry (Celtis laevigata), and cedar elm, with Texas persimmon, spiny hackberry (Celtis pallida), Wright acadia (Acacia wrightii), and anacua (Ehretia anacua) occurring as understory dominants. In later successional stands, western soapberry assumes prominence in the overstory canopy with cedar elm, great leadtree (Leucaena pulverulenta), sugarberry, honey mesquite (Prosopis glandulosa), and anacua [43]. Western soapberry occurs in many southwestern riparian woodlands which are considered climax or postclimax communities [6]. Western soapberry also grows well on infertile waste ground and may occur in some early seral communities. SEASONAL DEVELOPMENT : Fruits and flowers develop annually in a "characteristic growth flush" [34]. New vegetative shoots subsequently arise from an axillary bud located behind the site of the previous year's flowers and fruit [34]. Fruit ripens during September and October [40] and commonly persists until late winter or spring [16]. Generalized flowering and fruiting dates of western soapberry by geographic location are as follows: location flowering fruit ripe authority NM May-August ---- Lamb 1971 Southwest May-June ---- Vines 1960 n Great Plains mid-June October Stephens 1973 se CO March-June ---- Shaw & others 1989 Trans-Pecos, TX March-July ---- Powell 1988 TX May-June ---- Simpson 1988 Great Plains March-July ---- Great Plains Flora Association 1986 AZ May-August ---- Kearney & others 1960


SPECIES: Sapindus saponaria var. drummondii
FIRE ECOLOGY OR ADAPTATIONS : Most Southwestern riparian woodlands presumably burn infrequently. Recurrent fires in adjacent upland desert communities may eliminate or reduce invading shrubs such as western soapberry [11]. Specific adaptations to fire have not been identified in western soapberry. Plants may reoccupy a site through seed transported from adjacent unburned areas by birds. Postfire sprouting from underground rhizomes is possible but has not been documented. FIRE REGIMES : Find fire regime information for the plant communities in which this taxon may occur by entering the plant name in the FEIS home page under "Find Fire Regimes". POSTFIRE REGENERATION STRATEGY : survivor species; on-site surviving rhizomes off-site colonizer; seed carried by animals or water; postfire yr 1&2


SPECIES: Sapindus saponaria var. drummondii
IMMEDIATE FIRE EFFECT ON PLANT : Little documentation exists on the effect of fire on western soapberry. However, Simpson [32] reported that this species can spread through underground rhizomes. These underground regenerative portions of the plant could presumably survive even if aboveground foliage is consumed by fire. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Postfire response of western soapberry has not been documented. Postfire sprouting from underground rhizomes may occur. Western soapberry produces an abundance of seed annually [29], and establishment through off-site seed is also possible. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : NO-ENTRY FIRE MANAGEMENT CONSIDERATIONS : Bock and Bock [2] reported that prescribed fire is "difficult to manage and potentially very destructive" in established riparian woodlands of the Southwest. These relatively rare and fragile areas provide important food and cover for desert wildlife [30]. Because browse and cover are often limited in these areas, burning is not generally recommended [30].


SPECIES: Sapindus saponaria var. drummondii
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