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The vascular flora of an old-growth Columbia Bottomland Forest remnant, Brazoria County, Texas.

Abstract. -- A floristic survey of the Dance Bayou Unit, a 263 ha Columbia Bottomland forest stand within the San Bernard National Wildlife Refuge, was conducted in order to provide a checklist of the vascular flora of an old-growth Columbia Bottomland Forest remnant. Collecting trips were made to the refuge unit from November 2001 through September 2004, and resulted in a catalog of 356 species of vascular plants representing 83 families and 237 genera. The four largest families are Poaceae (54 sp.), Asteraceae (35 sp.), Cyperaceae (32 sp.), and Fabaceae (20 sp.). Non native species accounted for 15% (55 sp) of the total flora. Notes on physical and chemical soil properties, as well as forest ecological and physiognomic features are provided.

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The bottomland hardwood forests adjacent to the Brazos, Colorado, and San Bernard rivers of the upper Texas coast are known regionally as the Columbia Bottomlands (Fig. 1). The Columbia Bottomlands extend from the Texas coast, approximately 150 km inland, and includes parts of seven counties. It's estimated that the Columbia Bottomlands (known alternatively as Austin's Woods), comprised over 283,000 ha at the beginning of the last century (U. S. Fish and Wildlife Service 1997). Today, the forest covers about 71,632 ha, and the remaining stands are highly fragmented and continuously lost or degraded through residential and commercial development, overgrazing, timbering, and infestation of non native plants (U. S. Fish and Wildlife Service 1997; Barrow & Renne 2001; Barrow et al. 2003). Recent studies utilizing Geographic Information Systems suggested a loss of approximately 17% between 1979 and 1995 (Webb 1997).

The recognition of the importance of bottomland forests adjacent to the Gulf of Mexico as stopover and staging habitat for Nearctic-Neotropical migrant landbirds has emphasized the dire need for the conservation of a substantial area of the remaining tracts, and a deeper understanding of the ecological processes of these forests (Barrow et al. 2003). Millions of Nearctic-Neotropical migrant landbirds move through the coastal forests of the Gulf of Mexico during annual migration (Barrow et al. 2003). The Columbia Bottomlands provides the only expanse of forest adjacent to the Gulf of Mexico in Texas. An estimated 29 million Nearctic-Neotropical migrant landbirds represented by 65-70 species migrate through the Columbia Bottomlands annually (Barrow pers. comm.; U. S. Fish and Wildlife Service 1997).

Hamilton et al. (2005) included the Dance Bayou Unit in an enumeration of extant old growth bottomland forests of the southeast United States. The Dance Bayou Unit is a 263 ha Columbia Bottomland forest stand within the San Bernard National Wildlife Refuge (SBNWR), and administered by the U.S. Fish and Wildlife Service (USFWS). The Dance Bayou Unit does not lie within the boundaries of the SBNWR, but is a satellite unit located approximately 35 km NW of the refuge headquarters, near the town of West Columbia (Fig. 1). As suggested by Runkle (1982) for other old-growth remnants, the Dance Bayou Unit is without obvious large-scale human disturbance such as timbering, thinning, selective cutting, burning, or overgrazing, and likely represents climax vegetation. Some minor clearing has occurred to accommodate hunting, an abandoned county dirt-road, and a pipeline right-of-way, but the overall area disturbed by these activities was small. Other old-growth indicators include a diverse and uneven aged tree community, abundant standing snags and fallen trees, abundant large vines, tree fall gaps, and numerous large, uniquely shaped or super-emergent specimen trees (Hamilton et al. 2004). Old growth bottomland forest, like the Dance Bayou Unit, provides structural complexity known to be important for sustaining an abundance of forest dwelling birds (Hamilton et al. 2004; Barrow et al. 2000).

The significant natural resource and conservation priority that the Columbia Bottomlands represent and the apparent accelerating loss of the remaining areas gave rise to the study reported here. The purpose of this study was to provide a detailed account of the vascular flora and details of soil characteristics of an old-growth Columbia Bottomland forest in order to: (1) characterize its floristic uniqueness; (2) facilitate future quantitative and experimental studies of Columbia Bottomland forest community dynamics; (3) provide a benchmark for Columbia Bottomland forest management and restoration; and (4) provide a plant species list to supplement additional faunal studies at the Dance Bayou unit.

[FIGURE 1 OMITTED]

STUDY AREA

The Columbia Bottomlands lie within the Coastal Plain Province at the northern limit of the subtropical vegetation zone (Fenneman 1928; Good 1953). The forests of the Columbia Bottomlands formed on Holocene fluviatile deposits laid down by the major tributaries that traverse the region (Crenwelge et al. 1981; Geologic Atlas of Texas 1968). Three rivers transect the Columbia Bottomlands, the Brazos, Colorado, and San Bernard, all flowing generally southeasterly to the Gulf of Mexico (Fig. 1). The regional climate is moist subhumid mesothermal characterized by long hot summers and mild winters (Thornthwaite 1948). Average annual rainfall is 132 cm, with 60% occurring from April through September (Crenwelge et al. 1981). The average daily summer temperature is 27[degrees]C, and average daily winter temperature is 13[degrees]C (Crenwelge et al. 1981).

Soils mapped in the Dance Bayou Unit are Pledger clay and Asa silty clay loam, rarely flooded (Crenwelge et al. 1981). The Pledger and Asa soils formed in recent reddish, brownish, or yellowish clayey and micaceous loamy sediments which are characteristic of the Colorado River deposits in the Texas Gulf Coast Prairie Major Land Resource Area (Soil Survey Staff 1981; Miller 1986). The entry gate to the Dance Bayou Unit is located at 29[degrees]7' 7.73"N, 95[degrees] 47' 10.12"W in SW Brazoria County, Texas. The unit is bounded on all sides by private property, and traversed by Dance Bayou, a small distributary of the San Bernard River for which the unit is named.

MATERIALS AND METHODS

Topographical maps and color infrared aerial photos were examined in order to locate different habitats and plan fieldwork. Sporadic collecting trips were made to the refuge unit from November 2001 through September 2004. A complete set of voucher specimens were deposited to the Spring Branch Science Center Herbarium (SBSC) with some duplicates deposited to the Botanical Research Institute of Texas (BRIT) and the University of Western Ontario (UWO); herbarium acronyms follow Holmgren et al. 1990). When available, duplicates were deposited to other herbaria. Plant identifications were made using various regional manuals including Correll & Johnston (1970), Gould (1975), Godfrey (1988), Isely (1990), and Smith (1994). Some difficult specimens were presented to various experts for identification.

Field studies including soil profile descriptions of Pledger clay and Asa silty clay loam soils at the Dance Bayou Unit have been ongoing since August 1998. Soils mapped as Asa at the Dance Bayou Unit were within the Asa series range of characteristics and were not sampled. The Asa series type location is on a similar landscape, and physical and chemical analysis was obtained from the series type location characterization data. However, since no data was available for Pledger clay, physical and chemical analyses were conducted at various landscape positions and the results are included herewith.

RESULTS

Collecting trips yielded 356 species of vascular plants representing 83 families and 237 genera (Table 1). The four families containing the most species are Poaceae (54 sp.), Asteraceae (35 sp.), Cyperaceae (32 sp.), and Fabaceae (20 sp.). The largest genus is Carex with 19 species. One species, Alternanthera sessilis (sessile joyweed), is listed by the U.S. Department of Agriculture as a noxious weed. Non native species accounted for 15% (55 sp.) of the total species. No Federally-listed threatened or endangered plant species were found.

ANNOTATED CHECKLIST OF VASCULAR PLANT SPECIES OF THE DANCE BAYOU UNIT

Plant names are arranged by class, and then listed alphabetically within class by family, genus, and species using the classification system in Jones et al. (1997). Familiar synonymy for select species is provided in brackets. Each species is followed by a common name gleaned from regional manuals, and collection number for the first author, or other author if indicated. Non native species, based on review of Hatch et al. (1990) and Correll & Johnston (1970) are indicated by an asterisk (*).

POLYPODIOPSIDA (Ferns and Fern Allies)

ASPLENIACEAE

Asplenium platyneuron (L.) Britt., Sterns, & Poggenb., ebony spleenwort, 1854.

OPHIOGLOSSACEAE

Botrychium biternatum (Savigny) Underw., southern grape fern, 1906.

POLYPODIACEAE

Polypodium polypodioides (L.) Watt, resurrection fern, 1806.

THELYPTERIDACEAE

Thelypteris kunthii (Desv.) C. V. Morton, wide-spread maiden fern, 1761.

PINOPSIDA (Gymnosperms)

CUPRESSACEAE

Juniperus virginiana L. var. virginiana, eastern red-cedar, sight record.

LILIOPSIDA (Monocots)

ALISMATACEAE

Echinodorus beteroi (Spreng.) Fassett, beaked burhead, 2090

Echinodorus cordifolius (L.) Griseb. subsp. fluitans (Fassett) R. R. Haynes & L. B. Holm-Niels., heart-leaf burhead, 2075

Sagittaria graminea Michx. subsp. graminea, grass-leaf arrowhead, 1891.

Sagittaria platyphylla (Engelm.) J. G. Sm., delta arrowhead, 1892.

ALLIACEAE

Allium canadense L., Canada meadow onion, 1805.

ARACEAE

Arisaema dracontium (L.) Schott, green dragon, 1857.

ARECACEAE

Sabal minor (Jacq.) Pers., dwarf palmetto, 2177.

BROMELIACEAE

Tillandsia recurvata (L.) L., small ball moss, 1900.

Tillandsia usneoides (L.) L., Spanish moss, 2934.

COMMELINACEAE

Commelina diffusa N. L. Burnman, spreading day-flower, 2092.

CYPERACEAE

Carex basiantha Steud., basal-fruit caric-sedge, 1844.

Carex blanda Dewey, charming caric-sedge, 1890.

Carex bulbostylis Mack., globose caric-sedge, 1845.

Carex caroliniana Schwein., Carolina caric-sedge, 2458.

Carex cherokeensis Schwein., Cherokee caric-sedge, 1877.

Carex corrugata Fernald, wringle-fruit caric-sedge, 1843.

Carex crus-corvi Shuttlew.ex Kunze, crowfoot caric-sedge, 1894.

Carex flaccosperma Dewey, flaccid-fruit caric-sedge, 1856.

Carex frankii Kunth, Frank's caric-sedge, 2073.

Carex hyalinolepis Steud., hyaline-scale caric-sedge, 1947.

Carex leavenworthii Dewey, Leavenworth's caric-sedge, 1849.

Carex louisianica L. H. Bailey, Louisiana caric-sedge, 2025.

Carex lupuliformis Sartwell ex Dewey, hop-like caric-sedge, 2129

Carex lupulina Muhl. ex Willd., hop caric-sedge, 2032.

Carex oxylepis Torr. & Hook. var. oxylepis, sharp-scale caric-sedge, 1842.

Carex retroflexa Muhl. ex Willd., reflexed-fruit caric-sedge, 1886.

Carex tetrastachya Scheele, four-angled caric-sedge, 2115.

Carex texensis (Torr. ex L. H. Bailey) L. H. Bailey, Texas caric-sedge, 1847.

Carex tribuloides Wahlenb. var. sangamonensis Clokey, Sangamon caltrop caric-sedge, 2074.

Cyperus croceus Vahl, Baldwin's flat-sedge, 2193.

* Cyperus entrerianus Boeck., deeprooted sedge, 2095.

Cyperus esculentus L. var. esculentus, yellow nutgrass, 2334.

Cyperus ochraceus Vahl, pond flat-sedge, 2187.

Cyperus pseudovegetus Steud. var. pseudovegetus, marsh flat-sedge, 2114.

* Cyperus rotundus L., purple nutgrass, 2927.

Cyperus thyrsiflorus Jungh., coastal plain flat-sedge, 1945.

Cyperus virens Michx. var. virens, green flat-sedge, 2030.

Eleocharis acicularis (L.) Roem. & Schult. var. acicularis, needle spikerush, 2087.

Eleocharis montevidensis Kunth, sand spikerush, 2081.

Eleocharis palustris (L.) Roem. & Schult., marsh spikerush, 2353.

Kyllinga brevifolia Rottb., short-leaf spike-sedge, 2467.

Rhynchospora corniculata (Lam.) A. Gray, horned beakrush, 2088.

Scleria oligantha Michx., small-head nutrush, 1880.

IRIDACEAE

Herbertia lahue (J. Molina) P. Goldblatt, South Texas herbertia, 1887. endemic

Sisyrinchium langloisii Greene, dotted blue-eyed grass, 2465.

JUNCACEAE

Juncus acuminatus Michx., taper-tip rush, 2450.

Juncus effusus L., soft rush, 2463.

Juncus marginatus Rostk., grass-leaf rush, 2033.

Juncus tenuis Willd. var. tenuis, slender rush, 2082.

LEMNACEAE

Lemna obscura (Austin) Daubs, little duckweed, 2964.

Spirodela polyrhiza (L.) Schleid., duckmeat, 2965.

LILIACEAE

Nothoscordum bivalve (L.) Britt., crow-poison, 1768.

ORCHIDACEAE

Spiranthes ovalis Lindl.var. ovalis, nodding ladies'-tresses, Liggio s.n.

Spiranthes cernua (L.) Rich., oval ladies'-tresses, 2389.

POACEAE

Andropogon glomeratus (Walter) Britt., Sterns, & Poggenb. var. pumilus Vasey, bushy bluestem, 2356.

Andropogon virginicus L. var. virginicus, broom-sedge bluestem, 2397.

Arundinaria gigantea (Walter) Muhl. subsp. gigantea, giant cane, 2632.

* Bothriochloa ischaemum (L.) Keng, King Ranch bluestem, 2215.

Bothriochloa longipaniculata (F. Gould) K. Allred & F. Gould, long-spike silver blue-stem, 2237.

* Briza minor L., little quaking-grass, 1911.

* Bromus catharticus Vahl, rescue grass, 1869.

* Cenchrus spinifex Cav., coastal sand-bur, 2335.

Chasmanthium latifolium (Michx.) H. O. Yates, broad-leaf woodoats, 2223.

Chasmanthium laxum (L.) H. O. Yates var. sessiliflorum (Poiret) Wipff & S. D. Jones, hairy-collar woodoats, 2135.

* Chloris canterae Arechav. var. canterae, Paraguay windmillgrass, 2573.

* Cynodon dactylon (L.) Pers., Bermuda-grass, 2209.

* Dactyloctenium aegyptium (L.) P. Beauv., Egytian crow's-foot-grass, s.n.

Digitaria ciliaris (Retz.) Koeler var. ciliaris, fringed crab-grass, 2176.

* Echinochloa colona (L.) Link, jungle rice, 2333.

* Echinochloa crus-galli (L.) P. Beauv. var. crus-galli, large barn-yard-grass, 2100.

* Eleusine indica (L.) Gaertn. subsp. indica, goosefoot-grass, 2336.

Elymus virginicus L. var. virginicus, Virginia wildrye, 1949.

Hordeum pusillum Nutt., little barley, 1870.

Leersia lenticularis Michx., catchfly grass, 2105.

Leersia monandra Sw., bunch cut-grass, 2396.

Leersia virginica Willd., Virginia cut-grass, 2020.

Leptochloa panicea (Retz.) Ohwi subsp. brachiata (Steud.) N. Snow, branching sprangletop, 2235.

* Lolium arundinaceum (Schreb.) Darbysh., cane-like rye-grass, 2700.

* Lolium perenne L., perennial rye-grass, 1776.

Melica mutica Walter, two-flower melic-grass, 1767.

Muhlenbergia schreberi J. F. Gmel., nimblewill, 2021.

Nassella leucotricha (Trin. & Rupr.) R. W. Pohl, Texas winter grass, 2466.

* Oplismenus hirtellus (L.) P. Beauv. subsp. setarius (Lam.) Mez, basket-grass, 2226.

Panicum anceps Michx. var. anceps, beaked panic-grass, 2131.

Panicum commutatum Schult. var. commutatum, variable panic-grass, 1841.

Panicum gymnocarpon Elliott, swamp panic-grass, 2130.

Panicum laxiflorum Lam., open-flower rosette-grass, 2420.

Panicum rigidulum Nees var. rigidulum, red-top panic-grass, 2258.

Paspalum conjugatum P. J. Bergius, lividum Trin.], sour paspalum, 2221.

Paspalum denticulatum Trin. [Sy = Paspalum long-tom, 2197.

* Paspalum dilatatum Poiret, dallis-grass, 2014.

Paspalum langei (E. Fourn.) Nash, woodland paspalum, 2222.

* Paspalum notatum Flugge, bahia grass, 2113.

Paspalum repens P. J. Bergius var. fluitans (Elliott) Wipff & S. D. Jones, creeping water paspalum, 2188.

* Paspalum urvillei Steud., vasey-grass, 2152.

Phalaris angusta Nees ex Trin., timothy canary-grass, 1897.

Phalaris caroliniana Walter, Carolina canary-grass, 1895.

Poa annua L., annual blue-grass, 2399.

Poa autumnalis Muhl. ex Elliott, autumn blue-grass, 1840.

* Setaria pumila (Poiret) Roem. & Schult., bristle-grass, s.n.

* Sorghum halepense (L.) Pers., Johnson-grass, 2098.

Sphenopholis obtusata (Michx.) Scribn., prairie wedge-grass, 2462.

Sporobolus compositus (Poiret) Merr. var. compositus, dropseed, 2638.

Sporobolus indicus (L.) R. Br. var. indicus, smut grass, 2195.

* Stenotaphrum secundatum (Walter) Kuntze, St. Augustine grass, 2210.

Tridens flavus (L.) Hitch. var. flavus, purple-top tridens, 2351.

Urochloa platyphylla (Munro ex Wright) R. D. Webster, broadleaf liver-seed grass, 2574.

* Urochloa reptans (L.) Stapf, creeping liver-seed grass, 2245.

Zizaniopsis miliacea (Michx.) Doll & Asch., southern wild rice, 2461.

SMILACACEAE

Smilax bona-nox L., saw greenbrier, 2886.

Smilax rotundifolia L., common greenbrier, 1875.

Smilax smallii Morong, Small's greenbrier, 2024.

MAGNOLIOPSIDA (Dicots)

ACANTHACEAE

Dicliptera brachiata (Pursh) K. Spreng., branched fold-wing, 3055.

Hygrophila lacustris (Cham. & Schltdl.) Nees, gulf swampweed, 2076.

Justicia ovata (Walter) Lindau var. lanceolata (Chapm.) R. W. Long, lance-leaf water-willow, 2028.

Ruellia nudiflora (Engelm. ex A. Gray) Urban var. nudiflora, wild-petunia, 2224.

Ruellia strepens L., smooth wild-petunia, 2012.

ACERACEAE

Acer negundo L., box-elder, 1915.

AMARANTHACEAE

* Alternanthera sessilis (L.) R. Br. ex DC., sessile joyweed, 2106. Federal Noxious Weed

* Amaranthus viridis L., tropical green pigweed, 2928

Amaranthus rudis J. D. Sauer, water-hemp, 2243.

ANACARDIACEAE

Toxicodendron radicans (L.) Kuntze, poison-ivy, 2136.

APIACEAE

* Chaerophyllum tainturieri Hook., chervil, 2018.

Cyclospermum leptophyllum (Pers.) Sprague ex Britton & P. Wilson, slim-lobe celery, 2404.

Cynosciadium digitatum DC., finger dogshade, 1946.

Eryngium hookeri Walp., Hooker's eryngo, 2172.

Hydrocotyle verticillata Thunb., water-pennywort, 1876.

Sanicula canadensis L., Canadian sanicle, 2027.

Sanicula odorata (Raf.) Pryer & Phillippe, black snakeroot, 1861.

* Torilis nodosa (L.) Gaertn., knotted hedge-parsley, 1909.

Trepocarpus aethusae Nutt. ex DC., white nymph, 2019.

AQUIFOLIACEAE

Ilex decidua Walter, possumhaw, 2102.

Ilex opaca Sol. var. opaca, American holly, 2401.

Ilex vomitoria Aiton, yaupon holly, 2978.

ASCLEPIADACEAE

Asclepias perennis Walter, aquatic milkweed, 2031.

Asclepias viridis Walter, antelope-horn milkweed, 2139.

Matelea gonocarpos (Walter) Shinners, angle-pod milkvine, 2526.

ASTERACEAE

Iva annua L. var. annua, sea-coast sumpweed, 2359.

Acmella oppositifolia (Lam.) R. K. Jansen var. repens (Walter) R. K. Jansen, opposite-leaf creeping spot-flower, 2083.

Ambrosia psilostachya DC., western ragweed, 2634.

Ambrosia trifida L., giant ragweed, 2332.

Baccharis halimifolia L., eastern baccharis, 2338.

Bidens bipinnata L. var. biternatoides Sherff, six spanish needles, 2216.

Calyptocarpus vialis Less., straggler daisy, 2122.

Centaurea americana Nutt., basketflower, 2173.

Chlorocantha spinosa (Benth.) G. Nesom var. spinosa, spiny aster, 2358.

Conoclinium coelestinum (L.) DC., blue mistflower, 2185.

Coreopsis tinctoria Nutt., tickseed, 2094.

Eclipta prostrata (L.) L., yerba de tago, 2103.

Elephantopus carolinianus Raeusch., Carolina elephant's-foot, 2259.

Erigeron geiseri Shinners var. geiseri, Geiser's fleabane, Adams & Hannah s.n. endemic

Erigeron philadelphicus L., Philadelphia fleabane, 1838.

Eupatorium serotinum Michx., saw-leaf thoroughwort, 2387.

Fleischmannia incarnata (Walter) R.M. King & H. Rob., Fleischmann's thoroughwort, 2352.

* Hypochaeris microcephala (Sch. Bip.) Cabrera var. albiflora (Kuntze) Cabrera, white-flowered cat's-ear, 2029.

Krigia cespitosa (Raf.) K. L. Chambers, dwarf-dandelion, 2470.

Lactuca floridana (L.) Gaertn. var. floridana, woodland lettuce, 2329.

Mikania scandens (L.) Willd., climbing hempweed, 2637.

Packera tampicana (DC.) C. Jeffrey, Tampico butterweed, 1871.

Parthenium hysterophorus L., false ragweed, 2120.

Pluchea camphorata (L.) DC., camphorweed, 2328.

Pyrrhopappus carolinianus (Walter) DC., Carolina false dandelion, 2208.

Pyrrhopappus pauciflorus (D. Don) DC., small-flowered false dandelion, 1773.

Ratibida columnifera (Nutt.) Wooton & Standl., Mexican-hat, 2017.

Rudbeckia hirta L., brown-eyed susan, 2194.

Smallanthus uvedalia (L.) Mack. ex Small, bear's-foot leafcup, 3156.

Solidago canadensis L. var. scabra (Muhl. ex Willd.) Torr. & A. Gray, rough-leaf Canadian goldenrod, 2235.

* Sonchus oleraceus L., common sowthistle, 2232.

Symphyotrichum dumosum (L.) G. Nesom, bushy aster, 2395. (duplicate at BRIT)

Symphyotrichum racemosum (Elliott) G. Nesom var. subdumosum (K. Wiegand) G. Nesom, bush raceme aster, 2388. (duplicate at BRIT)

Verbesina virginica L. var. virginica, Virginia frostweed, 2178.

Vernonia missurica Raf., Missouri ironweed, 2633.

* Youngia japonica (L.) DC., Japanese hawkweed, 1881.

BIGNONIACEAE

Campsis radicans (L.) B. Seemann ex E. Bureau, trumper-creeper, 2116.

BORAGINACEAE

Heliotropium indicum L., Indian heliotrope, 2144.

Heliotropium procumbens Mill. var. procumbens, four-spike heliotrope, 2108.

Myosotis macrosperma Engelm., spring forget-me-not, 1839.

BRASSICACEAE

* Cardamine debilis D. Don, weak bittercress, 1779.

Lepidium virginicum L. var. medium (Greene) C.L. Hitchc., Virginia pepperwort, 1777.

Rorippa palustris (L.) Besser, yellowcress, 2091.

CAMPANULACEAE

Triodanis lamprosperma McVaugh, prairie venus' looking-glass, 2016.

CAPRIFOLIACEAE

* Lonicera japonica Thunb., Japanese honeysuckle, 1904.

Sambucus nigra L. var. canadensis (L.) B.L. Turner, common elderberry, 2132.

Symphoricarpos orbiculatus Moench, coralberry, 2180.

Viburnum dentatum L., southern toothed arrow-wood, 2089.

Viburnum rufidulum Raf., rusty blackhaw, 1905.

CARYOPHYLLACEAE

* Cerastium glomeratum Thuill., sticky mouse-ear chickweed, 1778.

Stellaria prostrata Baldwin ex Elliott, prostrate starwort, 2801.

CHENOPODIACEAE

* Chenopodium berlandieri Moq., Berlandier's goose-foot, 2192.

CONVOLVULACEAE

Dichondra carolinensis Michx., Carolina pony-foot, 1858.

Ipomoea cordatotriloba Dennst. var. cordatotriloba, tie-vine, 2119.

Ipomoea lacunosa L., white-star morning glory, 2257.

CORNACEAE

Cornus drummondii C. A. Mey., rough-leaf dogwood, 2013.

CRASSULACEAE

Penthorum sedoides L. subsp. sedoides, ditch stonecrop, 2527.

CUCURBITACEAE

Melothria pendula L. var. pendula, drooping melonette, 2217.

CUSCUTACEAE

Cuscuta pentagona Engelm., dodder, 2198.

EBENACEAE

Diospyros virginiana L., common persimmon, 2926.

EUPHORBIACEAE

Acalypha gracilens A. Gray, slender three-seeded mercury, 1759.

Acalypha rhomboidea Raf., rhombic-leaf three-seed mercury, 2142.

Caperonia palustris (L.) A. St.-Hil., marsh false-croton, 2143.

Chamaesyce nutans (Lag.) Small [Sy = Euphorbia nutans Lag.], eyebane sand-mat, 2156.

Chamaesyce serpens (Kunth) Small [Sy = Euphorbia serpens Kunth], matted sand-mat, 2212.

Croton capitatus Michx. var. lindheimeri (Engelm. & A. Gray) Mull. Arg., Lindheimer's hogwort croton, 2148.

Croton monanthogynus Michx., one-seed croton, 2339.

Euphorbia bicolor Engelm. & A. Gray, snow-on-the-prairie, 2171.

Euphorbia dentata Michx., toothed spurge, 2230.

Euphorbia spathulata Lam., warty spurge, 1863.

Phyllanthus pudens L. C. Wheeler, bird-seed leafflower, 2213.

* Triadica sebifera (L.) Small [Sy = Sapium sebiferum (L.) Roxb.], Chinese tallow-tree, 2096.

Tragia urticifolia Michx., nettle-leaf noseburn, 2078.

FABACEAE

* Albizia julibrissin Durazz., mimosa tree, sight record.

Amphicarpaea bracteata (L.) Fernald, American hogpeanut, 2331.

Desmanthus illinoensis (Michx.) C. MacMillan ex Robinson & Fern., Illinois bundleeflower, 2138.

Desmodium canescens (L.) DC., hoary ticktrefoil, 2151.

Desmodium glabellum (Michx.) DC., Dillenius' ticktrefoil, 2011.

Galactia volubilis (L.) Britt., twining milkpea, 2239.

Lathyrus pusillus Elliott, low pea-vine, 1865.

* Medicago arabica (L.) Huds., Arabian medick, 2454.

* Medicago lupulina L., black medick, 1867.

* Medicago polymorpha L., burclover, 1910.

* Melilotus indicus (L.) All., annual sourclover, 1908.

Mimosa strigillosa Torr. & A. Gray, pink sensitivebrier, 2111.

Neptunia pubescens Benth., prairie neptunia, 2207.

Rhynchosia minima (L.) DC. var. minima, least snoutbean, 2140.

Senna obtusifolia (L.) H.S. Irwin & Barneby, coffeeweed senna, 2107.

* Senna occidentalis (L.) Link, western senna, 3157

Sesbania drummondii (Rydb.) Cory, Drummond's rattlebush, 2225.

* Trifolium campestre Schreb. var. campestre, hop clover, 1893.

* Trifolium repens L. var. repens, white clover, 1769.

* Trifolium resupinatum L., Persian clover, 1866.

Vicia ludoviciana Nutt., Leavenworth's Louisiana vetch, 1913.

FAGACEAE

Quercus alba L., white oak, 2887.

Quercus nigra L., water oak, 2159.

Quercus shumardii Buckley, Shumard oak, 1758.

Quercus texana Buckley, [Sy = Q. nuttallii E. Palmer], Nuttall's oak, 2086.

Quercus virginiana Mill. var. virginiana, live oak, 2158.

GENTIANACEAE

Centaurium muhlenbergii (Griseb.) W. Wight ex Piper, Muhlenberg's centaury, 2524.

GERANIACEAE

Geranium carolinianum L. var. carolinianum, Carolina crane's-bill, 1864.

HALORAGACEAE

Proserpinaca palustris L. var. amblyogona Fernald, marsh mermaidweed, 2955.

JUGLANDACEAE

Carya aquatica (F. Michx.) Nutt., water hickory, 2157.

Carya illinoinensis (Wangenh.) K. Koch, sweet pecan, 2635.

Juglans nigra L., eastern black walnut, sight record.

LAMIACEAE

Lycopus virginicus L., Virginia water horehound, 2398.

Micromeria brownei (Sw.) Benth. var. pilosiuscula A. Gray, Browne's savory, 2219.

Monarda citriodora Cerv. ex Lag., lemon beebalm, 2015.

Physostegia intermedia (Nutt.) Engelm. & A. Gray, obedient-plant, 2449.

Prunella vulgaris L., selfheal, 2034.

Salvia lyrata L., lyre-leaf sage, 1860.

Scutellaria ovata Hill, egg-leaf skullcap, 2069.

Stachys crenata Raf., mouse-ear betony, 1874.

Teucrium canadense L. var. canadense, Canadian germander, 2184.

Teucrium cubense Jacq. var. cubense, costal germander, 2234.

LINACEAE

Linum berlandieri Hook., Berlandier's flax, 2471.

LOGANIACEAE

Spigelia texana (Torr. & A. Gray) A. DC., Texas pinkroot, 1944. endemic

LYTHRACEAE

Lythrum alatum Pursh var. lanceolatum (Elliott) Rothr., lance-leaf loosestrife, 2155.

MALVACEAE

Hibiscus moscheutos L. subsp. lasiocarpos (Cav.) O. Blanchard, woolly crimson-eyed rosemallow, 2196.

Malvaviscus drummondii Torr. & A. Gray, Drummond's waxmallow, 2153.

Modiola caroliniana (L.) G. Don, Carolina bristlymallow, 2889.

Sida rhombifolia L., rhombic-leaf fanpetals, 2218.

MELIACEAE

* Melia azedarach L., Chinaberry tree, 2455.

MENISPERMACEAE

Cocculus carolinus (L.) DC., Carolina snailseed, 2150.

MORACEAE

Morus rubra L., red mulberry, 1907.

OLEACEAE

Forestiera acuminata (Michx.) Poiret, eastern swamp-privet, 2026.

Forestiera ligustrina (Michx.) Poiret, upland forestiera, s.n.

Fraxinus pennsylvanica Marshall, green ash, 2124.

* Ligustrum aff. lucidum Aiton, wax leaf privet, sight record.

* Ligustrum sinense Lour., Chinese privet, 2803.

ONAGRACEAE

Gaura parviflora Lehm., velvet-leaf beeblossum, 2097.

Ludwigia glandulosa Walter, cylindric-fruit primrose-willow, 2084.

Ludwigia repens J. R. Forst., creeping primrose-willow, 2242.

Oenothera speciosa Nutt., pink evening-primrose, 1862.

OXALIDACEAE

* Oxalis debilis Kunth var. corymbosa (DC.) Lourteig, pink woodsorrel, 2469.

Oxalis dillenii Jacq., woodsorrel, 2206.

Oxalis violacea L., violet woodsorrel, 2391.

PASSIFLORACEAE

Passiflora incarnata L., purple passionflower, 2205.

Passiflora lutea L., yellow passion flower, 2330.

PHYTOLACCACEAE

Phytolacca americana L. var. americana, polk-salad, 2683.

PLANTAGINACEAE

Plantago rhodosperma Decne., red-seed plantain, 1859.

POLYGONACEAE

Brunnichia ovata (Walter) Shinners, American buckwheat-vine, 2183.

Polygonum hydropiperoides Michx., swamp smartweed, 2085.

Polygonum pensylvanicum L., Pennsylvania smartweed, 2357.

Polygonum punctatum Elliot, water smartweed, 1757.

Polygonum ramosissimum Michx. var. ramosissimum, bushy smartweed, 2240.

Polygonum setaceum Baldwin var. interjectum Fernald, bristly smartweed, 2525.

Rumex chrysocarpus Moris, golden-fruited dock, 2575.

* Rumex pulcher L., fiddle dock, 2930.

Rumex verticillatus L., swamp dock, 2099.

Tovara virginiana (L.) Raf., Virginia jumpseed, 2238.

PRIMULACEAE

* Anagallis arvensis L., common speedwell, 1775.I

* Anagallis minima (L.) E. H. L. Krause, small pimpernel, 2795.

Samolus valerandi L. subsp. parviflorus (Raf.) O. Hulten, Valerand's small-flowered brookweed, 1805.

RANUNCULACEAE

Anemone berlandieri Pritzel, ten-petal anemone, 1770.

Clematis crispa L., swamp clematis, 2229.

Ranunculus hispidus Michx. var. nitidus (Chapm.) T. Duncan, glowing bristly buttercup, 2439.

* Ranunculus muricatus L., spiny-seed buttercup, 1888.

* Ranunculus platensis A. Spreng., prairie buttercup, 2456.

Ranunculus pusillus Poiret, low buttercup, 2468.

* Ranunculus sardous Crantz, hairy buttercup, 1771.

RHAMNACEAE

Berchemia scandens (Hill) K. Koch, Alabama supplejack, 1896.

Rhamnus caroliniana Walter, Indian cherry, 2010.

ROSACEAE

Crataegus aff. spathulata Michx., little-hip hawthorn, 2885.

Crataegus glabriuscula Sarg., hawthorn, 2255. endemic (duplicate at UWO)

Crataegus series Molles, hawthorn, 2473. (duplicate at UWO)

Crataegus viridis L. var. viridis, green hawthorn, 2256. (duplicate at UWO)

Geum canadense Jacq. var. camporum (Rydb.) Fernald & Weath., white avens, 1948.

Prunus caroliniana Aiton, Carolina cherry-laurel, 1766.

Rubus argutus Link, highbush blackberry, 1878.

Rubus trivialis Michx., southern dewberry, 2419.

RUBIACEAE

Cephalanthus occidentalis L. var. californicus Benth., buttonbush, 2181.

Diodia virginiana L., Virginia buttonweed, 2211.

Galium aparine L., catchweed bedstraw, 1872.

* Galium tinctorium (L.) J. Scopoli, dye bedstraw, 1868.

* Sherardia arvensis L., pink spurwort, 1774.

RUTACEAE

Zanthoxylum clava-herculis L., Hercules' club, 2924.

SALICACEAE

Salix nigra Marshall, black willow, 1898.

SAPINDACEAE

Cardiospermum halicacabum L., common balloon-vine, 2092.

Sapindus saponaria L. var. drummondii (Hook. & Arn.) L. D. Benson, Drummond's western soapberry, 2079.

SAPOTACEAE

Sideroxylon lanuginosum Michx. subsp. oblongifolium (Nutt.) T. D. Penn., gum bumelia, 2137.

SAURURACEAE

Saururus cernuus L., lizard's-tail, 2070.

SCROPHULARIACEAE

Castilleja indivisa Engelm., Indian paintbrush, 2117.

Gratiola virginiana L. var. virginiana, Virginia hedge-hyssop, 1885.

Mecardonia procumbens (Mill.) Small, yellow flowered mecardonia, 2123.

Penstemon tenuis Small, sharp-sepal beard-tongue, 1889.

Veronica peregrina L., purslane speedwell, 1780.

SOLANACEAE

Physalis angulata L., cut-leaf groundcherry, 2109.

Solanum carolinense L. var. carolinense, Carolina nightshade, 2110.

STERCULIACEAE

Melochia pyramidata L. var. pyramidata, angle-pod broomwood, 2121.

TILIACEAE

Corchorus hirtus L. var. glabellus A. Gray, smooth orinoco jute, 2214.

ULMACEAE

Celtis laevigata Willd. var. laevigata, sugar hackberry, 1884.

Ulmus americana L., American elm, 2241.

Ulmus crassifolia Nutt., cedar elm, 2360.

URTICACEAE

Boehmeria cylindrica (L.) Sw., false-nettle, 2071.

Parietaria pensylvanica Muhl. ex Willd., Pennsylvania pellitory, 2931.

Urtica chamaedryoides Pursh, heart-leaf stinging-nettle, 1803.

VALERIANACEAE

Valerianella woodsiana (Torr. & A. Gray) Walp., Woods' cornsalad, 1912.

VERBENACEAE

Callicarpa americana L., American beautyberry, 2133.

Phyla lanceolata (Michx.) Greene, lance-leaf frogfruit, 2147.

* Verbena bonariensis L., South American vervain, 2220.

Verbena halei Small, Texas vervain, 2175.

* Verbena litoralis Kunth, [Sy = Verbena brasiliensis Vell.], Brazilian vervain, 1899.

Verbena urticifolia L. var. urticifolia, nettle-leaf vervain, 2134.

VIOLACEAE

Viola sororia Willd. var. sororia, bayou violet, 1772.

VISCACEAE

Phoradendron tomentosum (DC.) Engelm. ex A. Gray, mistletoe, 2400.

VITACEAE

Ampelopsis arborea (L.) Kohne, pepper-vine, 2101.

Ampelopsis cordata Michx., raccoon grape, 2925.

Parthenocissus quinquefolia (L.) Planch. var. quinquefolia, Virginia creeper, 2227.

Vitis aestivalis Michx. var. aestivalis, summer grape, 1901.

Vitis cinerea (Engelm.) Engelm. ex Millardet var. cinerea, sweet winter grape, 1902.

Vitis mustangensis Buckley, mustang grape, 1879.

Vitis palmata Vahl, catbird grape, 2182.

Asa soils at Dance Bayou are slightly acid to basic silty clay loams in slightly higher convex or nearly level positions on natural levees adjacent to active and abandoned stream channels (Table 2). Pledger soils are basic calcareous clays in broad nearly level flats or concave abandoned stream channels of the Columbia Bottomlands (Table 2). In undisturbed nonponded areas, Pledger soils have typical vertisol gilgai microtopography that consists of interconnected microhighs and small isolated microlows. Microlows make up about 10 percent of the area and range from oval areas 100 to 200 cm in diameter to oblong areas 100 to 300 cm long and 50 to 100 cm wide. Elevation difference between the bottom of the microlow and the top of the microhigh averages about 13 cm and ranges from 6 to 20 cm.

DISCUSSION

The 263 ha Dance Bayou unit has high native plant species richness (301 sp.; Table 1). Nixon (1986) reported native woody species richness ranged from 5 to 51 species in various bottomland hardwood plant communities in east Texas. Fifty-three native woody species occur at the Dance Bayou unit; the visual dominant over-story species across all landscape positions include Fraxinus pennsylvanica (green ash), Quercus virginiana var. virginiana (live oak), Celtis laevigata var. laevigata (sugar hackberry), Ulmus crassifolia (cedar elm), Sapindus saponaria var. drummondii (Drummond's western soapberry), Q. nigra (water oak), and U. americana (American elm). Dominant woody species at the Dance Bayou unit are similar to those previously reported from virgin east Texas forests, as well as bottomlands and riparian forests of north-central Oklahoma and the Edwards Plateau in south-central Texas (Nixon et al. 1977; 1991).

Several endemic species were encountered at the Dance Bayou unit. Crataegus glabriuscula (hawthorn) occurs in dry creek beds and bottomlands in north central and south Texas; Erigeron geiseri var. geiseri (Geiser's fleabane) occurs in open and usually sandy sites in central Texas; Herbertia lahue (South Texas herbertia) occurs in claey or sandy soils in prairies of south Texas; and Spigelia texana (Texas pinkroot) occurs in wooded slopes and floodplain woods in south Texas (Correll & Johnston 1970). Carex lupuliformis (hop-like caric-sedge) ocurs from Quebec, south to Florida and west to Texas, though it is always rare within its range (Jones & Hatch 1990). Several large populations of false hop-like caric-sedge occur in forested wetlands on Pledger soils in the Dance Bayou unit. Sixteen native plant species listed by Barrow et al. (2000) as important food resources for Nearctic-Neotropical migrant landbirds occur at the Dance Bayou unit. Of the 53 native woody species that occur at Dance Bayou, only 16 occur as canopy; the remainders are sub-canopy, shrubs, sub-shrubs, or vines. The numerous sub-canopy, shrub and vine species found beneath the forest canopy as well as in tree fall gaps contribute greatly to the structural architecture of the forest. Thus, under-brushing, thinning, and grazing will greatly decrease plant species richness and structural complexity in the Columbia Bottomlands.

Non native plant species were observed to be restricted to disturbed areas such as right-of-ways, roadsides, forest edges, and clearings, with two troubling exceptions. Tree fall gaps and seasonally flooded forested wetlands are susceptible to colonization by Triadica sebifera (Chinese tallow-tree). Invasions in tree fall gaps could potentially alter gap succession with disastrous effects on forest dynamics. Draw-downs of surface water in forested wetlands, whether during drought or seasonal dry cycles, facilitate infestations. Cyperus entrerianus (deeprooted sedge) is a pernicious weed and appears to be a serious threat to native plant diversity in the Columbia Bottomlands. Deeprooted sedge typically establishes along roadside and right-of-ways, and then advances through forest edges into undisturbed areas under closed-canopy forest. Other potentially problematic non native species at the Dance Bayou unit, and throughout the Columbia Bottomlands, include Albizia julibrissin (mimosa tree), Melia azedarach (Chinaberry tree), Ligustrum sp. (privet), and Lonicera japonica (Japanese honeysuckle). A Federally listed noxious weed, sessile joyweed, was encountered once along the banks of Dance Bayou early in this study, but has not been seen since.

Results of this study indicate that old-growth Columbia Bottomland forests are characterized by high native plant species richness, frequent tree falls followed by gap succession, large vines, abundant epiphytic growth, and conspicuous microtopography. Activities such as under-brushing, thinning, and grazing will greatly decrease plant species richness and available structural complexity. Attention should be given to non native species, and early detection and eradication, followed by periodic monitoring are warranted. The once vast forests adjacent to the Brazos, Colorado, and San Bernard rivers of the upper Texas coast remain today as remnant forest patches. Because of rapidly spreading commercial and residential development of the Houston Metroplex, much of the native flora of the Columbia Bottomlands may ultimately disappear.

ACKNOWLEDGMENTS

The senior author is grateful to Mike Lange, Thomas Adams (USFWS), and Tom Smith (NFWF) for their enthusiastic support of this project, and to Stanley Jones (Botanical Research Center), Guy Nesom (Botanical Research Institute of Texas), J. Wipff (Botanical Research Center-Oregon), and James Phipps (University of Western Ontario) for plant identifications. We thank Wylie Barrow (USGS) and Phillip Owens (Purdue University) for many helpful suggestions which improved an earlier version of this manuscript. We thank Larry Brown and Jason Singhurst for their critical review.

LITERATURE CITED

Barrow, W. C., Hamilton, R. B., Powell, M. A. & Ouchley, K. 2000. Contribution of landbird migration to the biological diversity of the northwest gulf coastal plain: Texas J. Sci., 52(4) Supplement: 151-172.

Barrow, W. C. & I. Renne. 2001. Interactions between migrant landbirds and an invasive exotic plant: the Chinese tallow tree. Flyway, 8(1): 11.

Barrow, W. C., L. A. Johnson Randall, M. S. Woodrey, J. Cox, E. Ruelas I., C. M. Riley, R. B. Hamilton & C. Eberly. 2003. Coastal forests of the Gulf of Mexico: A description and some thoughts on their conservation. USDA Forest Service Gen. Tech. Rep. PSW-GTR-191, 15 pp.

Correll, D. S. & M. C. Johnston. 1970. Manual of the Vascular Plants of Texas. Texas Research Foundation, Renner, Texas, 1881 pp.

Crenwelge, G. W., J. D. Crout, E. L. Griffin, M. L. Golden & J. K. Baker. 1981. Soil Survey of Brazoria County, Texas. United States Dept. of Agriculture, Soil Conservation Service, 140 pp.

Fenneman, N. M. 1928. Physiographic divisions of the United States. Annals Association American Geographers, 18: 261-353.

Geologic Atlas of Texas. 1968. University of texas Bureau of Economic Geology. Houston Sheet.

Godfrey, R.K. 1988. Trees, shrubs, and woody vines of Northern Florida and adjacent Georgia and Alabama. Univ. of Georgia Press, Athens, 734 pp.

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Gould, F.W. 1975. The grasses of Texas. Texas A & M Univ. Press, College Station, Texas, 653 pp.

Hamilton, R. B., W. C. Barrow, Jr. & K. Ouchley. 2005. Old-growth bottomland hardwood forests as bird habitat; implications for contemporary management. Pp. 373-388, in Ecology and management of bottomland hardwood systems: the state of our understanding (L. H. Fredrickson, S. L. King, and R. M. Kaminski, eds.), University of Missouri-Columbia. Gaylor Memorial Special Publication No. 10. Puxico, Missouri.

Holmgren, P. K., N. H. Holmgren & L. C. Barnett. 1990. Index herbariorum Part I: The herbaria of the world. New York Botanical Garden. New York.

Hatch, S.L., K.N. Gandhi & L. E. Brown. 1990. Checklist of the vascular plants of Texas. Texas Agric. Exp. Sta. Bill. MP-1655, 157 pp.

Isely, D. 1990. Vascular flora of the Southeastern United States, Volume 3, Part 2, Leguminosae (Fabaceae). Univ. of North Carolina Press, Chapel Hill, 258 pp.

Jones, S. D. & S. L. Hatch. 1990. Synopsis of Carex Section Lupulinae (Cyperaceae) in Texas. Sida, 14(1):87-99.

Jones, S. D., J. K. Wipff & P.M. Montgomery. 1997. Vascular plants of Texas: A comprehensive checklist including synonymy, bibliography, and index. University of Texas Press, Austin, Texas, 404 pp.

Miller, W. L. 1986. Soil Survey of Jackson County, Texas. United States Dept. of Agriculture, Soil Conservation Service, 147 pp.

Nixon, E. S. 1986. Bottomland hardwood community structure in East Texas. Pp. 8-19 in C. A. McMahan & R. G. Frye, eds., Bottomland hardwoods in Texas: Proceedings of an interagency workshop on status and ecology. Texas Parks and Wildlife Department. PWD-RP-7100-133-3/87, 170 pp.

Nixon, E. S., R. L. Willett & P. W. Cox. 1977. Woody vegetation of a virgin forest in an East Texas river bottom. Castanea, 42:227-236.

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DKR at: david_rosen@fws.gov

David J. Rosen and Wesley L. Miller

U.S. Fish and Wildlife Service, 17629 El Camino Real, Suite 211

Houston, Texas 77058-3051 and

Natural Resources Conservation Service

312 S. Main St., Room 310, Federal Building

Victoria, Texas 77901
Table 1. Taxonomic summary of the vascular plants of the Dance Bayou
Unit; San Bernard National Wildlife Refuge.

 Species
 Families Genera Native Non Native Total

Polypodiopsida (ferns) 4 4 4 0 4
Pinopsida (gymnosperms) 1 1 1 0 1
Liliopsida (monocots) 14 50 90 22 112
Magnoliopsida (dicots) 64 182 206 33 239
Totals 83 237 301 55 356

Table 2. Select Asa and Pledger soil properties including particle size
distribution, texture class, pH, organic matter content, and chemical
analysis. Parameters not measured are indicated by a dash (-).

Soil Horizon Depth Particle size Texture pH Organic
 (cm) (%) Class (a) Matter (%)
 sand silt clay

Asa A1 0-16 14 49 37 SiCL 6.8 3.1
 A2 16-40 21 46 33 CL 7.6 1.9
 Bw 40-75 11 58 31 SiCL 7.6 0.9
Pledger Bk 75-100 9 56 35 SiCL 8.0 0.6
microlow A 0-14 1 25 74 C 7.2 7.1
 Bss 14-100 1 25 74 C 7.0 5.4
Pledger A 0-10 6 27 67 C 7.4 5.3
microhigh Bw 10-46 6 26 68 C 7.6 5.0
 Bss 46-100 7 33 60 C 7.8 1.0

Soil Horizon Ca Mg Na K Fe Mn
 (%) (%) (b)
 meq * 100 [g.sup.-1]

Asa A1 23.1 2.4 0.1 0.8 - -
 A2 51.1 2.1 0.1 0.6 - -
 Bw 49.5 1.8 0.1 0.4 - -
Pledger Bk 58.6 3.9 0.1 0.5 - -
microlow A 40.6 5.0 0.2 2.2 1.9 0.1
 Bss 60.3 5.4 0.1 1.7 2.0 0.1
Pledger A - 4.4 0.4 1.7 2.1 0.1
microhigh Bw - 4.4 0.5 1.4 2.0 Tr
 Bss - 7.1 0.8 0.7 1.8 Tr

(a) SiCL-Silty Clay Loam, CL-Clay Loam, C-Clay. (b) Tr-trace (<0.1).
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Author:Rosen, David J.; Miller, Wesley L.
Publication:The Texas Journal of Science
Geographic Code:1U7TX
Date:Aug 1, 2005
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