Index of Species Information

SPECIES:  Ziziphus obtusifolia


SPECIES: Ziziphus obtusifolia
AUTHORSHIP AND CITATION : Sullivan, Janet. 1993. Ziziphus obtusifolia. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].
ABBREVIATION : ZIZOBT SYNONYMS : Condalia lycioides (Gray) Weberb Condalia obtusifolia (Hook.) Weberb Condaliopsis lycioides (Gray) Suess. SCS PLANT CODE : ZIOB COMMON NAMES : lotebush lotebrush lote gumdrop tree Texas buckthorn bluebush graythorn greythorn whitethorn chaparral chaparro prieto abrojo clepe TAXONOMY : The accepted scientific name for lotebush is Ziziphus obtusifolia (T & G) Gray [36]. Accepted varieties are as follows [36,43]: Ziziphus obtusifolia var. canescens (Gray) Johnston Ziziphus obtusifolia var. obtusifolia LIFE FORM : Shrub FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


SPECIES: Ziziphus obtusifolia
GENERAL DISTRIBUTION : Lotebush occurs from Arizona, New Mexico, Texas, and southwestern Oklahoma south to San Luis Potosi and Vera Cruz, Mexico [36]. ECOSYSTEMS :    FRES30  Desert shrub    FRES31  Shinnery    FRES32  Texas savanna    FRES33  Southwestern shrubsteppe    FRES35  Pinyon - juniper    FRES38  Plains grasslands    FRES39  Prairie STATES :      AZ  OK  NM  TX  MEXICO BLM PHYSIOGRAPHIC REGIONS :     7  Lower Basin and Range    13  Rocky Mountain Piedmont    14  Great Plains KUCHLER PLANT ASSOCIATIONS :    K027  Mesquite bosque    K031  Oak - juniper woodlands    K044  Creosotebush - tarbush    K045  Ceniza shrub    K054  Grama - tobosa prairie    K058  Grama - tobosa shrubsteppe    K059  Trans-Pecos shrub savanna    K060  Mesquite savanna    K061  Mesquite - acacia savanna    K065  Grama - buffalograss    K071  Shinnery    K085  Mesquite - buffalograss    K086  Juniper - oak savanna    K087  Mesquite - oak savanna SAF COVER TYPES :     66  Ashe juniper - redberry (Pinchot) juniper     67  Mohrs ("shin") oak     68  Mesquite    241  Western live oak    242  Mesquite SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : Lotebush is a common member of honey mesquite (Prosopis glandulosa var. glandulosa) or mesquite (P. laevigata) communities.  It is usually a subdominant but is sometimes codominant with honey mesquite [1,39]. Other common subdominants in these communities include four-winged saltbush (Atriplex canescens), wolfberry (Lycium spp.), and in southeastern New Mexico, javalinabush (Microrhamnus ericoides), and broom snakeweed (Gutierrezia sarothrae) [33]. On upland sites with finer textured soils, honey mesquite communities (with lotebush) are often associated with other plant species that include pricky pear (Opuntia imbricata var. imbricata, O. polycantha, O. leptocaulis), and algerita (Mahonia trifoliolata) [44]. In communities where lotebush is codominant, common understory species include buffalograss (Buchloe dactyloides), sideoats grama (Bouteloua curtipendula), crabgrass (Digitaria california), Wright's threeawn (Aristida wrightii), Texas wintergrass (Stipa leucotrica), and broomweed (Gutierrezia dracunculoides) [2]. In succulent-scrub upland communities in the Chihuahuan Desert, lotebush is associated with ocotillo (Fouquieria splendens), coldenia (Coldenia greggii), catclaw acacia (Acacia greggii), cenizos (Leucophyllum minus, L.  frutescens), Condalias (Condalia spp.), lippia (Aloysia wrightii), and littleleaf sumac (Rhus microphylla) [14,36].  Lotebush is a frequent member of Ashe juniper (Juniperus ashei) or Pinchot juniper (J. pinchotii) communities on the Edwards Plateau and the Rolling Plains of Texas [18,34].


SPECIES: Ziziphus obtusifolia
IMPORTANCE TO LIVESTOCK AND WILDLIFE : The fruit of lotebush is eaten by gray foxes, raccoons, ringtails, and various birds including scaled quail, white-winged doves, band-tailed pigeons, mockingbirds, northern orioles, phainopeplas, white-necked ravens, curved-billed thrashers and golden-fronted woodpeckers [26,31,50].  The twigs are browsed by white-tailed deer but are probably not preferred [15].  Cattle browse lotebush, but it is apparently of low preference [49]. The southern plains woodrat makes extensive but not exclusive use of lotebush twigs for construction of houses, although it prefers sites closer to prickly pear (Opuntia spp.) plants [47].  Lotebush is a preferred nest site for a number of bird species [39]. PALATABILITY : The mealy drupe is edible for humans but is not palatable [50].  It is preferred by some species of birds and small mammals [31]. NUTRITIONAL VALUE : Lotebush browse is of medium food value for white-tailed deer [15]. In vitro dry matter digestibility averaged for all four seasons was 45.4 percent.  Leaf crude protein as a percentage of dry weight ranged from 19 percent in May to 40 percent in March [49]. Nutritional value (as percentage of dry weight) for lotebush fruits is as follows [17]: crude protein      11 phosphorus          0.19 calcium             0.35 magnesium           0.12 potassium           1.23 sodium              0.04 COVER VALUE : Lotebush is a primary source of loafing cover in fall, winter, and spring for northern bobwhite.  It is preferred in winter for its closed, spinescent canopy that provides overhead concealment and good protection from climatic extremes.  Northern bobwhite use only larger lotebush plants [40]. VALUE FOR REHABILITATION OF DISTURBED SITES : NO-ENTRY OTHER USES AND VALUES : The roots of lotebush can be used as a soap substitute and also as a treatment for wounds and sores of domestic animals [50].  Until recently, the fruits were eaten in small quantites by the Pima Indians of the Gila River region [38]. OTHER MANAGEMENT CONSIDERATIONS : On the Rolling Plains of northwestern Texas, lotebush only rarely develops into wide-ranging dense stands that require control measures, but it but can become a problem locally.  Where it does occur in dense stands that impede management of livestock, Scifres and Kothmann [42] recommend thinning with individual plant treatments, either mechanical or chemical. Removal of top growth is insufficient to control lotebush.  After 30 days, 90 percent of lotebush plants clipped 1 inch (2.5 cm) above the soil line had sprouted [42].  More stems per plant are produced when top growth is removed to approximately 2 inches (5 cm) above the soil than when it is removed to ground line, to below the first woody lateral shoot, or left undisturbed [19,42].   Lotebush is resistant or partially resistant to many herbicides, but is susceptible to basal sprays of picloram [8,32].  Scifres and Kothmann [42] recommend either basal applications of 2,4,5-T plus picloram, picloram pellets or dicamba granules for control of lotebush. Dodd [16] achieved effective control of lotebush by root plowing followed by raking.  Other authors agree that mechanical control methods which completely uproot the plants offer more promise for control than those which only remove top growth [32,42].  These methods, however, result in poorer range conditions (more annual invaders) than chemical treatments.  This can be at least partially compensated for by artificial seeding [32]. In an area of mixed brush dominated by honey mesquite (that includes lotebush), Scifres and others [41] recommend a variable rate pattern of herbicide application that could be more economical than strip-applied patterns.  Such variable rate patterns can be made more site specific and take into account different brush species' susceptibility to herbicides and the particular potential of each site.  This type of application also results in the patchy brush that is preferred by wildlife, particularly white-tailed deer. Management for wildlife habitat should leave large lotebush clones or individuals intact.  Sprouting lotebush plants (where top growth was removed) often have a prostrate or rosette growth form that is useless to nesting birds [39].


SPECIES: Ziziphus obtusifolia
GENERAL BOTANICAL CHARACTERISTICS : Lotebush is a native, deciduous medium-sized shrub.  It is densely branched and leafy.  It generally grows up to 6 feet (2 m) tall but can reach heights of 13 feet (4 m) [21,36,42].  The branches are light gray, covered with a waxy bloom, and have thorn-tipped branchlets.  The fruit is a drupe with one stone [36]. RAUNKIAER LIFE FORM :       Phanerophyte REGENERATION PROCESSES : Sexual reproduction:  Lotebush reproduces by seed.  There is apparently no innate dormancy of seed or seed-coat inhibition; Vora [51] reported a mean emergence of 95 percent from fresh, depulped seed, and concluded that no pretreatment is necessary for germination.  Seeds are dispersed by birds and small mammals [50]. Asexual reproduction: Top-killed lotebush will sprout from the root crown or, if that is removed, from the roots [19,42]. SITE CHARACTERISTICS : Lotebush is common on dry plains, mesas, and slopes [24].  Lotebush occurs on limestone- and igneous-rock-derived substrates in highly eroded areas, and on rocky prairie hillsides [21,36].  It is tolerant of xeric conditions but can also be found on more mesic soils, such as those immediately surrounding a desert oasis [5].  Historically, lotebush was probably restricted to dissected uplands and rocky places along with its woody associates.  In the past 50 to 300 years there has been an increase in the density of woody species (including lotebush) on grasslands [3,4,7,56].  Lotebush tends to occur in aggregated stands in low densities [42].  In Arizona and in Trans-Pecos Texas, lotebush is found from 1,000 to 5,500 feet (300-1,700 m) elevation [24,36]. In the Chihuahuan Desert, lotebush is associated with creosotebush (Larrea tridentata), guayacan (Guaiacum angustifolium), lechuguilla (Agave lechuguilla), Texas sotol (Dasylirion texanum), and Texas persimmon (Diospyros texana).  Associated grasses in this region include chino grama (Bouteloua ramosa), red grama (B. trifida), black grama (B. eriopoda), sideoats grama (B. curtipendula), threeawn (Aristida spp.), and tridens (Tridens spp.) [36].  In Saltillo, Mexico, lotebush occurs in grassland-shrub communities with yucca (Yucca rigida) and chino grama (B. breviseta) [30]. SUCCESSIONAL STATUS : Facultative Seral Species In a study of the mechanisms by which woody species are encroaching on Texas grasslands, Archer [3,4] found that the original colonizer of grass swards is usually honey mesquite.  A combination of factors appears to be responsible for the increased establishment of honey mesquite and associated species in grasslands:  grazing and increased dispersal of mesquite seeds by livestock, fire suppression, and possible climatic changes [4].  Honey mesquite creates conditions for the establishment of other woody species, either by altering soil and moisture conditions, or simply by virtue of the fact that birds choose to roost in it and disperse seeds of other species around its base. Lotebush colonizes mesquite clusters around 35 to 46 years after the mesquite is established [3]. Pinchot juniper appears to facilitate lotebush establishment on high plains sites with shallow clay loam soils.  On these sites lotebush is positively associated with large Pinchot juniper trees.  On Rolling Plains sites with deeper clay loam soils, there is no such association. Whether the association is caused by birds dispersing seeds while roosting in the tree, or by juniper alteration of microhabitat to be more favorable for germination of lotebush was not determined by the study [35].  Lotebush in turn reduces Pinchot juniper growth rates during October and November, though its zone of influence is relatively small [34]. SEASONAL DEVELOPMENT : In the Rio Grande Valley, lotebush abcisses leaves as early as November, loses most or all leaves by mid-December, and new growth is evident by early February [52].  Lotebush flowers in April and May in the Rio Grande Valley, and as late as July farther north [21,52].  Fruit ripens by June in the Rio Grande Valley [52]. Germination of seeds probably takes place in summer or fall or as soon as moisture conditions permit [51].


SPECIES: Ziziphus obtusifolia
FIRE ECOLOGY OR ADAPTATIONS : Lotebush is very tolerant of fire; even when 100 percent top-kill is achieved with a prescribed fire, usually very little root-kill will occur [46]. 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 :    Small shrub, adventitious-bud root crown


SPECIES: Ziziphus obtusifolia
IMMEDIATE FIRE EFFECT ON PLANT : Lotebush is top-killed by most fires [46]. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Lotebush is not easily killed by fire.  Neuenschwander and others [29] found that they killed none of 50 marked plants with a prescribed fire, even though all of the plants showed at least some damage and most were top-killed.  Similar results occurred on a prescribed burn where 88 percent of the plants were top-killed, but only 5 percent did not sprout [53].  Box and others [10,11] achieved from 87 to 100 percent lotebush top-kill with prescribed fire, but only 10 to 40 percent mortality.  The 40 percent figure was the highest recorded fire mortality for lotebush found in the literature reviewed for this write-up, and may be artificially high, as it was recorded only for the first growing season after the fire . Lotebush sprouts readily after being top-killed by fire, either from the stem tissue of the root crown, or directly from the roots if all stem tissue is killed (root sprouting does not occur if any stem tissue is intact) [19,42,46].  Neuenschwander and others [29] found that in a dry year, lotebush may not sprout the first growing season following fire top-kill, but with adequate moisture in the second or third growing season it will then respond. With adequate moisture, growth rates are very high for sprouts during the first few years after fire top-kill, then growth slows to a gradual increase (which can still be three times that of unburned plants) until maximum heights are reached about 6 to 7 years after a fire [29]. Lotebush canopy height was reduced 32 percent 3 years after a prescribed fire in a mixed grass-mesquite community [46].  Lotebush and other brush recovered to prefire canopy diameters (probably due to an increased number of stems per individual) by the end of one growing season after a prescribed fire [22]. Lotebush regains its original position in a community much more slowly than four-winged saltbush [54].  Flower and seed production occurs as soon as 3 to 4 years after a fire [29]. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : This fire study provides information on postfire responses of plant species in communities that include lotebush: FIRE MANAGEMENT CONSIDERATIONS : Fire is not very effective in controlling brush in southern Texas unless some form of pretreatment is practiced.  Fire alone produces uneven and patchy burns, with large islands of brush left intact.  Any type of mechanical control that crushes or knocks down large shrubs enhances the effect of fire.  Lotebush in particular is not adversely affected by fire and will increase in the number of stems per plant after fire.  Removal of lotebush requires mechanical uprooting or treatment with effective herbicides before burning [8,10,11,12]. Many fire prescriptions in mixed grass-shrub communities have a number of objectives that can include an increase in herbage yields, an increase in utilization of coarse grasses, an increase in the availability of forage, to remove dead woody material, to improve wildlife habitat and to control undesirable shrubs, cacti and cool season grasses [55]. Northern bobwhite respond favorably to increased herbaceous growth following fire, providing that some woody cover is maintained.  Burning in western Texas can cause a critical loss of northern bobwhite cover unless some of the large lotebush and honey mesquite plants are left unburned [45].  Hot fires where all lotebush plants are top-killed will reduce the amount of nesting sites available for at least 1 year after the fire, and more likely for up to 6 to 7 years [39].  Cooler fires that have patchy coverage will leave some larger, single-stemmed lotebush individuals untouched and available as nesting cover [39]. Fire prescriptions that have wildlife habitat as a management goal should preserve larger lotebush clones or individuals.  Lotebush that sprouts after top-kill is not used for nest sites nor is it useful loafing cover for bobwhite quail until the sixth or seventh growing season after the fire.  The costs of dozing firelines around the larger lotebush can be offset by the sale of hunting leases [39,40]. Control of lotebush after a prescribed fire can be aided by pasturing Spanish goats on the burned site.  These goats prefer lotebush sprouts, especially where there is easy access (i.e. old stems are burned away) [46].


SPECIES: Ziziphus obtusifolia
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