DIVISION 1. PTERIDOPHYTA

LYCOPODIACEAE CLUB-MOSS FAMILY

Lycopodiella prostrata (R. M. Harper) Cranfill. Lycopodium prostratum R. M. Harper; Lycopodium alopecuroides L. var. pinnatum (Chapm.) Lloyd & Underw. CREEPING CLUB-MOSS. Native perennial. Reported from Travis County by Correll (1956) on the basis of a single specimen, B. C. Tharp s.n., purportedly collected from a Blackland Prairie site; the disposition of this specimen was not provided. It is possible that a Tharp specimen at TEX-LL, collected 15 Oct 1939 from Austin County, was mistakenly attributed to the city of Austin and thus to Travis County. Lycopodiella prostrata occurs mainly in mesic to wet pine forests of the southeastern United States, and its presence in Travis County seems unlikely.

Specimens: None at TEX-LL, Mar 1996. Previous Travis County floras: none. References: Correll, 1956; Wagner & Beitel, 1993.

SELAGINELLACEAE SPIKE-MOSS FAMILY

Selaginella apoda (L.) Spring. Selaginella apus (L.) Spring. MEADOW SPIKE-MOSS. Native perennial. Rare on wet rocks near shaded springs and seeps, occasionally on stream banks and other perennially moist and at least partially shaded sites.

Specimens: West Cave, on moist bank of brook, 8 Dec 1939, F. McAllister s.n. (TEX-LL); Watkins Ranch, cypress bog, 8 Oct 1948, Tharp et al. 53-570 (TEX-LL); lakeside bluff, J. B. Watkins Ranch, 29 Jul 1950, B. C. Tharp & C. S. York 50-39 (TEX-LL); Watkins Ranch above Cow Creek on Lake Travis, 2 Jun 1951, B. C. Tharp et al. 51-957 (TEX-LL); seep-moistened exposures of Edwards Limestone on floor of damp rock shelter in N-facing bluff, S bank of Bear Creek ca. 0.85 airmiles NW of int. of Bliss Spillar Rd. and Gunsmith Dr., 24 Nov 1999, W. R. Carr & J. Maresh 18644 (TEX-LL). Previous Travis County floras: Young, 1920. References: Correll, 1956; Valdespino, 1993.

Selaginella arenicola Underw. subsp. riddellii (Van Eselt.) Tryon. Selaginella riddellii Van Eselt. RIDDELL SPIKE-MOSS. Native perennial. Rather common in unshaded areas on sandy, gravelly soils derived from igneous rocks of the Llano Uplift, as well as in deep sandy soils over Eocene deposits on the coastal plain. In northwestern Travis County it is local in dry sandy soils over ancient Colorado River terrace deposits derived at least in part from igneous rocks of the Llano Uplift, and may still be present in undeveloped patches of post oak woodland on similar substrates within the city of Austin. Apparently rare in or absent from limestone soils.

Specimens: Post oak ridges west of Austin, 12 Jan 1901, W. H. Long s.n. (TEX-LL); dry ground, post oak woods, Austin, no date, M. S. Young s.n. (TEX-LL); gravelly hills near Austin, 20 May 1944, B. C. Tharp 44027 (BRIT/SMU, TEX-LL); locally abundant in well drained cobbly sandy soils over Pleistocene Colorado River terrace deposits, in open post oak-Ashe juniper woodland on moderate slope, ca. 500 ft. W of Singleton Rd. ca. 0.7 mi. S of Post Oak Bend Cemetery, S end of Gloster Bend Resource Area, 23 Apr 1991, W. R. Carr & P. McNeal 11111 (TEX-LL). Previous Travis County floras: Young, 1920. References: Correll, 1956; Valdespino, 1993.

Selaginella wrightii Hieron. WRIGHT SPIKE-MOSS. Native perennial. Of doubtful status, included here solely on the basis of an apparently unvouchered report from Wild Basin (Williams, 1977). In the western part of the Edwards Plateau, this spike-moss is commonly encountered in very shallow soils on otherwise barren limestone exposures.

Specimens: None at TEX-LL, Mar 1996. Previous Travis County floras: none. References: Correll, 1956; Valdespino, 1993.

ISOETACEAE QUILLWORT FAMILY

Isoetes melanopoda Gay & Durieu. BLACKFOOT QUILLWORT. Native perennial. Rare in seasonally wet soils in open areas. Easily overlooked, perhaps more common in Travis County than indicated by the dearth of collections.

Specimens: Wet clay on seep on unshaded W bank of Shoal Creek ca. 200-300 ft. S of 45th St., Austin, 17 Jun 1986, W. R. Carr 7590 (BRIT/SMU) and 29 Jun 1986, W. R. Carr 7669 (UVST). Previous Travis County floras: none. References: Correll, 1956; Taylor et al., 1993.

EQUISETACEAE HORSETAIL FAMILY

Equisetum hyemale L. subsp. affine (Engelm.) J. Calder & R. L. Taylor. Equisetum robustum A. Braun var. affine Engelm.; Equisetum prealtum Raf. WINTER HORSETAIL. Native perennial. Uncommon in moist soils along shaded to unshaded banks of rivers and creeks and shorelines of impoundments.

Specimens: Barton Creek, banks in shaded position, 15 Jan 1901, A. M. Ferguson s.n. (TEX-LL); Barton Creek, 1927, J. F. Normand s.n. (TEX-LL); Barton Creek, 15 Mar 1929, F. Normand s.n. (TEX-LL); lakeside bluff, J. B. Watkins Ranch, 29 Jul 1950, B. C. Tharp & C. S. York 50-38 (TEX-LL); Watkins Ranch above Cow Creek on Lake Travis, 2 Jun 1951, B. C. Tharp et al. 51-960 (TEX-LL). Previous Travis County floras: Young, 1920; Lynch, 1974. References: Correll, 1956; Hauke, 1993.

Equisetum laevigatum A. Braun. Equisetum kansanum J. H. Schaffner. SMOOTH HORSETAIL. Native perennial. Uncommon in moist soils along shaded to unshaded banks of rivers and creeks and shorelines of impoundments.

Specimens: Moist sandy bank of Lake Austin at Lake Austin (Emma Long) City Park, 21 Apr 1985, W. R. Carr 6358 (SEU). Previous Travis County floras: none. Other reports: West Cave Preserve (Lemke et al., 1984). References: Correll, 1956; Hauke, 1993.

OPHIOGLOSSACEAE ADDER'S-TONGUE FAMILY

Ophioglossum engelmannii Prantl. ADDER'S-TONGUE. Native perennial. Apparently rare, collected from moist soil along Bull Creek and reported from "rich soil in woods near [Tom Miller] dam" (Young, 1920). No recent reports or specimens.

Specimens: Moist soil, Bull Creek near the head, 22 May 1918, M. S. Young s.n. (TEX-LL); Austin, 6 Oct 1923, R. H. Painter s.n. (TEX-LL). Previous Travis County floras: Young, 1920. References: Correll, 1956; Wagner & Wagner, 1993.

OSMUNDACEAE ROYAL FERN FAMILY

Osmunda regalis L. var. spectabilis (Willd.) Gray. ROYAL FERN. Native perennial. Of doubtful status in our area, included solely on the basis of a 1901 specimen collected by Bray and Long. Although correctly determined, it seems likely that the specimen's attribution to Travis County is erroneous. The accompanying label originally read "Anemia mexicana," which suggests the possibility that the label and the specimen are unrelated, i.e., that Bray and Long collected Anemia mexicana in Travis County but at some later date their label became attached to someone else's specimen of Osmunda regalis from a location probably far to the east. Royal fern is a denizen of mesic forests throughout much of the eastern half of North America; its presence in Travis County would be quite unexpected and noteworthy if true.

Specimens: [To county only], Feb 1901, Bray & Long s.n. (TEX-LL). Previous Travis County floras: none. References: Correll, 1956; Whetstone & Atkinson, 1993.

ANEMIACEAE NAKED FERN FAMILY

Anemia mexicana Klotzsch. MEXICAN FERN. Native perennial. A species of the Edwards Plateau and northern Mexico, here at or near the northeastern limit of its current distribution. Occasional in steep rocky wooded limestone canyons; apparently more common south of the Colorado River than north.

Specimens: Ten miles up Colorado River from Austin, 9 Feb 1901, Bray & Long s.n. (TEX-LL); Austin, 6 Apr 1918, M. S. Young s.n. (TEX-LL); limestone gorge, 6 Apr 1918, M. S. Young s.n. (TEX-LL); near Austin, 22 Apr 1918, M. S. Young s.n. (TEX-LL); Devil's Canyon, 25 Nov 1984, W. R. Carr 6173 (BRIT/SMU, UVST, TEX-LL); Barton Creek near Scottish Woods Trail, 30 June 1988, W. R. Carr & D. A. Brown 9035 (TEX-LL); juniper-oak woodland in limestone canyon, ca. 2.1 airmiles NW of jct. St. Rt. 71 and R.M. 620, 23 Oct 1992, W. R. Carr, D. Keddy-Hector & P. Turner 12481 (TEX-LL); rare in loamy duff on steep slope of Glen Rose Limestone, wooded mesic limestone canyon at NE corner of Sandy Creek County Park, 2 Jul 1990, W. R. Carr 15590 (TEX-LL). Previous Travis County floras: Young, 1920. References: Correll, 1956; Mickel, 1993.

PTERIDACEAE MAIDENHAIR FERN FAMILY

Adiantum capillus-veneris L. SOUTHERN MAIDENHAIR FERN. Native perennial. Common on wet, seepy limestone cliff-faces, often occurring as horizontal bands rooted in a layer of crumbly marl or travertine immediately above a layer of impermeable rock.

Specimens: Numerous sheets at TEX-LL, Mar 1996. Previous Travis County floras: Young, 1920; Lynch, 1974. References: Correll, 1956; Windham, 1993.

Argyrochosma dealbata (Pursh) M. Windham. Notholaena dealbata (Pursh) Kunze. POWDERY CLOAKFERN. Native perennial. Uncommon, epipetric, often on dry solution-pitted rimrock along wooded limestone ravines, often with Cheilanthes alabamensis, Cheilanthes horridula and Asplenium resiliens.

Specimens: bluff, Onion Creek, 25 Apr 1913, M. S. Young s.n. (TEX-LL); dry rock crevices along the Pedernales, 12 mi NW of Bee Cave, 23 July 1947, D. S. Correll 13417 (TEX-LL); face of limestone cliff, Lake Travis, ca. 2 mi above Cow Creek, 22 May 1956, B. C. Tharp s.n. (TEX-LL); Pedernales River bridge on St. Rt. 71, 14 Nov 1968, D. Seigler & W. Renold 979 (TEX-LL), 26 Apr 1969, D. Seigler & E. Rodriguez 1198 (TEX-LL); top of cliffs downstream from Miller Dam on Colorado River, 8 Jan 1969, D. Seigler 1035 (TEX-LL); Bull Creek, 29 Mar 1984, W. R. Carr 5982 (TEX-LL); dry, partially shaded limestone outcrops on rimrock at top of slope on S side of Nauman Cove, near SW edge of Pace Bend Park, 16 Apr 1991, W. R. Carr 11073 (TEX-LL). Previous Travis County floras: Young, 1920; Lynch, 1974. References: Correll, 1956; Windham, 1993.

Astrolepis integerrima (Hook.) D. Benham & M. Windham. Cheilanthes integerrima (Hook.) Mickel; Notholaena sinuata (Lag.) Kaulf. var. integerrima Hook. WAVYLEAF CLOAKFERN. Native perennial. A species of epipetric habits, common on dry limestone outcrops farther west on the Edwards Plateau but rare in Travis County. No recent reports or specimens.

Specimens: Austin, upper Barton Creek, 2 May 1924, R. H. Painter s.n. (TEX-LL). Previous Travis County floras: none. References: Correll, 1956; Windham, 1993.

Cheilanthes alabamensis (Buckl.) Kunze. ALABAMA LIPFERN. Native perennial. Common in humus and loamy soils and on dry limestone outcrops in wooded ravines.

Specimens: Numerous sheets at TEX-LL, 1991. Previous Travis County floras: Young, 1920; Lynch, 1974. References: Correll, 1956; Windham, 1993.

Cheilanthes horridula Maxon. ROUGH LIPFERN. Native perennial. Uncommon, epipetric on dry limestone outcrops in wooded ravines or on exposed rimrock, often with Cheilanthes alabamensis.

Specimens: Dry bluff near head of Bull Creek, East Branch, 22 May 1918, E. J. Palmer s.n. (TEX-LL); about 6 mi NW of Bee Cave, 23 Jul 1946, D. S. Correll 13413 (TEX-LL); limestone exposures of Mt. Bonnell near Austin, 24 Jun 1946, C. C. Albers, F. A. Barkley & B. H. Warnock 46454 (TEX-LL); limestone outcrops on steep S-facing slope, S side of Barton Creek, 100-200 ft. E of Loop 360 bridge, Barton Creek Greenbelt, 15 Dec 1990, W. R. Carr 10913 (TEX-LL). Previous Travis County floras: none. References: Correll, 1956; Windham, 1993.

Pellaea atropurpurea (L.) Link. PURPLE CLIFFBRAKE. Native perennial. Common in loamy soils in rocky wooded limestone ravines; also on limestone rock outcrops, often with Cheilanthes alabamensis.

Specimens: Canyon below dam on Colorado River, Jan 1901, A. M. Ferguson s.n. (TEX-LL); near mouth of Bull Creek on leaf mould, shady moist gorge, 20 Apr 1901, A. M. Ferguson s.n. (TEX-LL); on river bank above Austin, Bull Creek, 21 Apr 1901, A. M. Ferguson s.n. (TEX-LL); Austin, 10 Oct 1907, H. H. York s.n. (TEX-LL); limestone ledge, Austin, 20 May 1933, B. C. Tharp s.n. (TEX-LL); Bull Creek, 3 Oct 1945, B. H. Warnock 45-38 (TEX-LL); Bull Creek, 22 Apr 1984, W. R. Carr 6046 (TEX-LL). Previous Travis County floras: Young, 1920; Lynch, 1974. References: Correll, 1956; Windham, 1993.

Pellaea ovata (Desv.) Weath. Pellaea flexuosa (Kaulf.) Link. ZIGZAG CLIFFBRAKE. Native perennial. Uncommon, epipetric on exposed limestone or in dry humus and clay on rubble slopes in wooded ravines; more common south of the Colorado River than north.

Specimens: Correll (1956) cited several specimens from Travis County; material at TEX-LL was on loan in Mar 1996 and was not examined. Previous Travis County floras: Young, 1920; Lynch, 1974. Other reports: Travis Audubon Wildlife Sanctuary (Lyter, 1986). References: Correll, 1956; Windham, 1993.

Pellaea wrightiana Hook. Pellaea ternifolia (Cav.) Link. var. wrightiana (Hook.) A. Tryon. WRIGHT CLIFFBRAKE. Native perennial. Common on dry granite and gneiss exposures in the Llano Uplift area just to the northwest, but known in Travis County from a single specimen (S. B. Buckley s.n., disposition and date not provided) cited by Correll (1956).

Specimens: None at TEX-LL, Mar 1996. Previous Travis County floras: none. References: Correll, 1956; Windham, 1993.

THELYPTERIDACEAE MARSH FERN FAMILY

Thelypteris ovata St. John var. lindheimeri (C. Chr.) A. R. Sm. Thelypteris kunthii (Desv.) Morton, in part; Dryopteris normalis Christ. var. lindheimeri Christ. LINDHEIMER SHIELDFERN. Native perennial. Frequent in moist loamy to silty soil along shaded banks of rivers and perennial streams; occasionally with Adiantum capillus-veneris on seepy limestone cliff faces and undisturbed travertine deposits.

Specimens: Bull Creek, 5 Sep 1982, W. R. Carr 4283 (TEX-LL). Additional specimens were cited by Correll (1956). Previous Travis County floras: Young, 1920 (as Dryopteris patens). References: Correll, 1956; Smith, 1993c.

ASPLENIACEAE SPLEENWORT FAMILY

Asplenium resiliens Kunze. LITTLE EBONY SPLEENWORT. Native perennial. Uncommon, usually epipetric on dry solution-pitted rimrock along wooded limestone ravines, often with Cheilanthes alabamensis and Cheilanthes horridula.

Specimens: Numerous sheets at TEX-LL, 1991. Previous Travis County floras: Young, 1920; Lynch, 1974. References: Correll, 1956; Wagner, Moran & Werth, 1993.

DRYOPTERIDACEAE WOOD FERN FAMILY

Cyrtomium falcatum (L. f.) Presl. ASIAN HOLLYFERN. Introduced perennial. An ornamental widely utilized in Austin landscapes, locally naturalized in shaded rock shelters of Stillhouse Hollow in the Bull Creek watershed, where it occurs in large numbers on moist limestone boulders fallen from rimrock, a habitat normally occupied by Aquilegia canadensis, Adiantum capillus-veneris, Thelypteris ovata var. lindheimeri, etc. No other naturalized populations are presently known from our area.

Specimens: Apparently naturalized on moist limestone boulders in rock shelter at springs, Stillhouse Hollow, Bull Creek, 31 Oct 1982, W. R. Carr 4492 (UVST) and 14 Apr 1984, W. R. Carr 6019 (BRIT/SMU). Previous Travis County floras: none. References: Smith, 1993a.

Woodsia obtusa (Spreng.) Torr. COMMON WOODSIA. Native perennial. Common in sandy to loamy soils in mesic woodlands to the east, and on intermittently wet outcrops of granite and gneiss in the Llano Uplift to the northwest, but apparently rare in Travis County. No recent reports or specimens.

Specimens: none at TEX-LL in Mar 1996. Correll (1956) cited one specimen from Travis County: Palmer 12140 (disposition not provided; date probably 1919). Previous Travis County floras: none. References: Correll, 1956; Smith, 1993a.

POLYPODIACEAE POLYPODY FAMILY

Polypodium polypodioides (L.) Watt. var. michauxianum Weath. RESURRECTION FERN. Native perennial. An epiphytic fern of the southeastern United States, here at the southwestern limit of its distribution. There are apparently no recent specimens from our area, but Tom Patterson (pers. comm., 11 May 1996) reported seeing a large population in trees along a stretch of Bee Creek near Toro Canyon Road during the 1980's.

Specimens: On oak, Pease Park, Austin, 15 Dec 1901, W. H. Long, Jr. s.n. (TEX-LL); near dam, Austin, 13 Feb 1916, B. C. Tharp s.n. (TEX-LL). Previous Travis County floras: Young, 1920. References: Correll, 1956; Smith, 1993b.

MARSILEACEAE WATER-CLOVER FAMILY

Marsilea macropoda A. Braun. BIGFOOT WATER-CLOVER. Native perennial. Apparently rare in wet soils of creekbottoms and riverbanks.

Specimens: material at TEX-LL was on loan in Mar 1996 and was not examined. However, Johnson (1986) cited two specimens: Shoal Creek, Austin, 15 Apr 1901, Long s.n. (GH, MO, NY, TAES, TEX-LL); Austin, Colorado River floodplain, 11 Mar 1928, B. C. Tharp s.n. (B, NY, PH, US). Previous Travis County floras: Lynch, 1974. References: Correll, 1956; Johnson, 1986; Johnson, 1993.

Marsilea vestita Hook. & Grev. Marsilea mucronata A. Braun.; Marsilea uncinata A. Braun.; Marsilea tenuifolia Kunze. WATER-CLOVER. Native perennial. Common in ephemerally or perennially wet clayey soils along margins of creeks, rivers, stock tanks and other impoundments.

Specimens: Material at TEX-LL was on loan in Mar 1996 and was not examined. However, Johnson (1986) cited three specimens: along Onion Creek, 8.5 mi S of Colorado River in Austin, D. S. Correll & H. B. Correll 29940 (TEX-LL, MO, UC); Austin, banks of the Colorado River, Hall 860 (BM, F, G, GH, K, MO, NY, US); Manchaca, E. J. Palmer 12148 (GH, MO, US). Previous Travis County floras: Young, 1920; Lynch, 1974. References: Correll, 1956; Johnson, 1986; Johnson, 1993.

AZOLLACEAE AZOLLA FAMILY

Azolla caroliniana Willd. MOSQUITO-FERN. Native perennial. Rare, presently known only from the surface of quiet water near the shoreline of Lake Walter E. Long; these plants may represent a recent introduction to the Travis County flora. Its occurrence on shallow backwaters of other reservoirs should be expected.

Specimens: Floating on shallow still water among tule stems, etc., S shoreline of Lake Walter E. Long, 500-1000 ft. W of boat ramp, 25 Dec 1984, W. R. Carr et al. 6188 (BRIT/SMU, SEU). Previous Travis County floras: none. References: Correll, 1956; Lumpkin, 1993.

DIVISION 2. SPERMATOPHYTA

CLASS 1. GYMNOSPERMAE

CUPRESSACEAE CYPRESS FAMILY

Juniperus ashei Buchh. Sabina sabinoides (H.B.K.) Nees. ASHE JUNIPER, CEDAR. Native tree or large shrub. Abundant, perhaps the most characteristic woody plant species of limestone uplands in the western half of the county.

Specimens: Numerous sheets at TEX-LL. Previous Travis County floras: Young, 1920; Lynch, 1974. References: Correll, 1966; Watson & Eckenwalder, 1993.

Juniperus virginiana L. Sabina virginiana (L.) Ant. EASTERN RED CEDAR. Native tree. Common, replacing Juniperus ashei to some extent in various soils in the eastern half of the county, but occurring with it at Walnut Creek Park (P. Turner, 1996) and in some mesic limestone canyons (Bro. D. Lynch, pers. comm.).

Specimens: Numerous sheets at TEX-LL. Previous Travis County floras: Young, 1920; Lynch, 1974. References: Correll, 1966; Watson & Eckenwalder, 1993.

EPHEDRACEAE JOINTFIR FAMILY

Ephedra antisyphilitica C. A. Mey. JOINTFIR. Native shrub. Rare on dry exposed limestone ledges and bluffs; more common to the south and west of Travis County. The population near Tom Miller Dam, represented by many of our early collections, is still extant, as is a cluster on the Rodgers Tract on the Balcones Canyonlands NWR (Sexton, 1996).

Specimens: Bluffs of Bee Creek, 2 Oct 1900, Long & Ferguson s.n. (TEX-LL); canyon below dam on Colorado, 13 Apr 1901, Long & Ferguson s.n. (TEX-LL); near dam, Austin, 22 Feb 1908, H. H. York s.n. (TEX-LL); bluff, Barton Creek, 30 Nov 1913, M. S. Young s.n. (TEX-LL); Austin, 1 Feb 1934, E. Whitehouse s.n. (TEX-LL); Austin, 5 Apr 1954, B. C. Tharp s.n. (TEX-LL); W bank of Colorado River just S of low water bridge (Red Bud Trail), 13 Nov 1960, J. D. Graham GA-10 (TEX-LL); limestone bluffs along Colorado River, one plant under the overhang immediately above the Town Lake [sic; actually Lake Austin] Dam at the Nature trail on Red Bud Lane, 10 Nov 1965, J. A. Mears 1033 (TEX-LL); bluffs along Pedernales River at rest area at St. Rt. 71 bridge, 2 May 1991, W. R. Carr 11128 (TEX-LL). Correll (1966) cited a specimen collected by Elihu Hall at Mt. Bonnell on 27 May 1872; the disposition of this specimen is unknown. Previous Travis County floras: Young, 1920 (as Ephedra nevadensis Wats., misapplied); Lynch, 1974. References: Correll, 1966; Stevenson, 1993.

TAXODIACEAE BALDCYPRESS FAMILY

Taxodium distichum (L.) Rich. BALDCYPRESS. Native tree. Rare to locally frequent in gallery woodlands along major perennial creeks and along shorelines of impoundments of the Colorado River.

Specimens: Numerous sheets at TEX-LL. Previous Travis County floras: Young, 1920; Lynch, 1974. References: Correll, 1966; Watson & Eckenwalder, 1993.

CLASS 2. ANGIOSPERMAE

SUBCLASS 1. MONOCOTYLEDONEAE

TYPHACEAE CAT-TAIL FAMILY

Typha domingensis Pers. NARROWLEAF CAT-TAIL. Native perennial. The common cat-tail in our area, found in wet soils along reservoirs, stock tanks, rivers and streams, roadside ditches.

Specimens: Austin, below F. M. [Feeble-Minded] Colony, 6 Jun 1921, B. C. Tharp s.n. (TEX-LL); Dry Creek near Austin, 23 Jun 1921, B. C. Tharp s.n. (TE-LL); dry creek on Bull Creek, 23 Jun 1924, B. C. Tharp 749 (TEX-LL); Austin Lake shore under Mt. Bonnell, 12 Aug 1943, F. A. Barkley 6085 (TEX-LL); Lake Long NE shoreline, 6 Jul 1984, F. R. Barrie 807 (TEX-LL); Town Lake at Johnson Creek, 18 May 1986, W. R. Carr & M. A. Wade 7463 (TEX-LL); Austin, Lake Long, inlet off bay of Lake Long, shallow water, 12 Aug 1988, Bro. D. Lynch, M. Campbell & J. Gee 9846 (SEU). Previous Travis County floras: Lynch, 1974.

Typha latifolia L. BROADLEAF CAT-TAIL. Native perennial. The current status of this species in our area is unclear. Unvouchered older reports, such as "in ponds of the Insane Asylum and of the University campus" (Young, 1920), may be based on Typha domingensis.

Specimens: Swale, wet black soil, St. Edwards University campus, 4 Jun 1954, Bro. D. Lynch C.S.C. s.n. (TEX-LL). Previous Travis County floras: Young, 1920; Lynch, 1974.

ZANNICHELLIACEAE HORNED PONDWEED FAMILY

Zannichellia palustris L. COMMON POOLMAT. Native submersed aquatic. Occasional in clear water of streams and rivers. Reported by Young (1920) as "abundant in Barton Creek and the Asylum ponds."

Specimens: Barton Creek, Austin, 12 Sep 1936, B. C. Tharp s.n. (SEU); Lake Walter E. Long, 2 Sep 1987, C. W. Sexton & N. McClintock s.n. (COA); shallow water near N shoreline of Lake Austin at Selma Hughes Park, 1 airmile NE of Lakeland Park, 22 Aug 1982, W. R. Carr 4232 (BRIT/SMU) and 20 Aug 1988, W. R. Carr 9159; NW Austin, Loop 360 at Balcones Fault Historical Marker N of Spicewood Springs Rd., submersed in clear water of stream [Bull Creek], 23 Apr 1983, B. Ertter 4769 (TEX-LL); pond, Barnes Hollow, Webster Tract, Balcones Canyonlands NWR, 9 Jan 1995, C. W. Sexton s.n. (BCNWR); intermittent pond in gravel, Shaw Tract, Balcones Canyonlands NWR, 15 Jun 1995, C. W. Sexton s.n. (BCNWR); Barton Springs Pool, Zilker Park, 15 Sep 1997, D. A. Chamberlain s.n. (TEX-LL). Previous Travis County floras: Young, 1920; Lynch, 1974. Other reports: Walnut Creek Park (P. Turner, 1996).

POTAMOGETONACEAE PONDWEED FAMILY

Potamogeton crispus L. CURLY PONDWEED. Naturalized submersed aquatic. Rare in flowing water of Colorado River. Introduced from the Old World, curly pondweed has proliferated to nuisance proportions in lakes and ponds in the northeastern United States. At present, it is rather rare in Travis County.

Specimens: [To county only], 15 Jun 1942, B. C. Tharp s.n. (SEU, TEX-LL); growing in rapid current about three feet deep, forming dense colonies in Colorado River about 5 miles below Austin, 1 Jun 1943, F. A. Barkley 13310 (TEX-LL); from shallow water along the edge of Lake Austin, 25 Aug 1944, L. Taylor and F. A. Barkley 14651 (TEX-LL); in shallow water near N shoreline of Lake Austin at Selma Hughes Park, 20 Aug 1988, W. R. Carr & M. L. Price 9157 (BRIT/SMU); rare, with Myriophyllum sp., submersed in normally clear water in quiet western side-channel of Colorado River, ca. 500 ft. N of Red Bud Trail bridge below Tom Miller Dam, Austin, 5 Jun 1994, W. R. Carr, P. McNeal & J. Gleason 13886 (TEX-LL). Previous Travis County floras: none. References: Ogden, 1966.

Potamogeton diversifolius Raf. THREADLEAF PONDWEED. Native aquatic perennial. Rather common in eastern half of Texas but rare in our area, known from a single collection from a small stock tank.

Specimens: locally frequent with Najas guadalupensis in small stock tank in clearing in live oak - juniper woodland on Glen Rose caliche flat, E side of main entrance road on Baker Tract (a Prop 2 tract) at 90^o turn ca. 0.6 mi S of gate on R. M. 1826, ca. 1.0 airmiles SSW of R. M. 1826 bridge over Slaughter Creek, 19 Apr 2000, W. R. Carr & P. Turner 18851 (TEX-LL). Previous Travis County floras: none. References: Ogden, 1966.

Potamogeton illinoensis Morong. Potamogeton lucens L. ILLINOIS PONDWEED. Native submersed aquatic perennial. Common in perennial streams and pools over limestone in western half of county; also in both impounded and free-flowing stretches of Colorado River.

Specimens: Barton Creek Springs in swift flowing water, 15 Jan 1901, A. M. Ferguson s.n. (TEX-LL) and Dec 1901, A. M. Ferguson s.n. (TEX-LL); Austin, 10 Oct 1908, H. H. York s.n. (TEX-LL); Bull Creek, Austin, fall 1920, B. C. Tharp 2181 (TEX-LL); Barton Creek, Austin, 12 Sep 1936, B. C. Tharp s.n. (TEX-LL) and 20 Aug 1940, B. C. Tharp s.n. (SEU, TEX-LL); from shallow water along the edge of Lake Austin, 24 Aug 1944, L. Taylor and F. A. Barkley 14547 (TEX-LL); in pool of clear water with limestone bottom, lower Bull Creek, 18 May 1946, J. Adamcik, C. M. Rowell, and F. A. Barkley 16T221 (TEX-LL); Barton Creek downstream from Barton Springs, submerged aquatic, 10 May 1970, Bro. D. Lynch 9459 (SEU); quiet water under baldcypress, spring run below Hamilton Pool, 28 Aug 1982, W. R. Carr 4256 (UVST); in shallow water near north shoreline of Lake Austin at Selma Hughes Park, 20 Aug 1988, W. R. Carr & M. L. Price 9158 (BRIT/SMU, TEX-LL); Colorado River behind National Wildflower Research Center, 11 Sep 1988, K. D. Cleveland s.n. (TEX-LL). Previous Travis County floras: Young, 1920; Lynch, 1974. References: Ogden, 1966.

Potamogeton nodosus Poir. THICKLEAF PONDWEED. Native aquatic perennial. Occasional in ponds, reservoirs, and slow-moving water of perennial or nearly perennial streams.

Specimens: From shallow water along the edge of Lake Austin, 25 Aug 1944, L. Taylor and F. A. Barkley 14646 (TEX-LL); SEU farm, pond, 4 Jul 1962, Bro. D. Lynch 9457 (SEU); 1/2 mi S of Mt. Bonnell, shallow water, W side of Lake Austin, 16 Sep 1962, Bro. D. Lynch 9458 (SEU); Lake Long, NE shoreline, abundant, 6 Jul 1984, F. R. Barrie 819 (TEX-LL); shaded backwater along W bank of Colorado River ca. 100 ft. N of Red Bud Trail, 2 Sep 1982, W. R. Carr 4273 (UVST, TEX-LL); shallow water along unshaded S shoreline of Lake Walter E. Long ca. 1 mi W of dam, 25 Oct 1986, W. R. Carr & E. A. Kutac 7294 (BRIT/SMU); margin of small lake on N side of Bloor Rd., 27 Sep 1987, W. R. Carr 8730 (TEX-LL); Austin, Lake Long, shallow water, light shade to unshaded, 12 Aug 1988, Bro. D. Lynch, M. Campbell & J. Gee 9847 (SEU) and 23 Aug 1988, Bro. D. Lynch & Bro. D. Steffer 7828 (SEU); Colorado River behind National Wildflower Research Center, 11 Sep 1988, K. D. Cleveland s.n. (TEX-LL). Previous Travis County floras: Lynch, 1974. References: Ogden, 1966.

Potamogeton pectinatus L. SAGO PONDWEED. Native submersed aquatic. Occasional in ponds, reservoirs, and slow-moving water of perennial or nearly perennial streams.

Specimens: From shallow water along the edge of Lake Austin, 25 Aug 1944, L. Taylor and F. A. Barkley 14648 (TEX-LL); Lake Walter E. Long, 2 Sep 1987, C. W. Sexton & N. McClintock s.n. (COA); Colorado River behind National Wildflower Research Center, 11 Sep 1988, K. D. Cleveland s.n. (TEX-LL). Previous Travis County floras: none. References: Ogden, 1966.

Potamogeton pusillus L. subsp. pusillus. BABY PONDWEED. Native submersed aquatic. Occasional in ponds, reservoirs, and slow-moving water of perennial or nearly perennial streams.

Specimens: Barton Creek, 12 Sep 1936, B. C. Tharp s.n. (TEX-LL); cold water about 2 feet deep in Barton Springs NW of Austin, 5 Aug 1944, G. Arroyos G. 102 (TEX-LL); deep water of Barton Spring NW of Austin, 6 Aug 1944, M. Thurlow 1 (TEX-LL); forming dense colonies in Colorado River about 5 miles below Austin, 1 Jun 1943, F. A. Barkley 13313 (TEX-LL); rare, with Zannichellia palustris in sandy bottom, clear cool shallow water along N bank of Lake Austin at Selma Hughes Park, 25 Aug 1988, W. R. Carr, M. L. Price & T. Gonzalez 9161 (TEX-LL) and 22 Jul 1996, W. R. Carr 15630 (TEX-LL). Previous Travis County floras: none. References: Haynes, 1974; Ogden, 1966.

NAJADACEAE WATER-NYMPH FAMILY

Najas guadalupensis (Spreng.) Magnus. var. guadalupensis. GUADALUPE WATER-NAIAD. Native submersed aquatic. Perhaps the most common submersed aquatic vascular plant in our area, in flowing water of the Colorado River and all major creeks as well as in quiet water of ponds and stock tanks.

Specimens: numerous sheets at TEX-LL, Mar 1996. Previous Travis County floras: none. References: Haynes, 1979.

Najas marina L. HOLLY-LEAF WATER-NAIAD, SPINY WATER-NAIAD. Native submersed aquatic. Rare in Texas and in our area as well. No recent specimens or reports.

Specimens: From shallow water along the edge of Lake Austin, 25 Aug 1944, L. Taylor and F. A. Barkley 14649 (TEX-LL). Previous Travis County floras: none. References: Haynes, 1979; Stuckey, 1985.

ALISMACEAE WATER-PLANTAIN FAMILY

Echinodorus berteroi (Spreng.) Fassett. Echinodorus rostratus (Nutt.) Engelm., incl. var. lanceolatus Engelm. BURHEAD. Native annual. Occasional in wet soils of sandy alluvial bars and mudflats along perennial streams.

Specimens: Walnut Creek, Watters Station, 22 Apr 1901, Long & Ferguson s.n. (TEX-LL); ditch along I & GN RR S of Feeble-Minded Colony, Austin, 25 Jun 1920, B. C. Tharp s.n. (TEX-LL); Austin, 10 May 1933, B. C. Tharp s.n. (TEX-LL); water of small pool near Barton Springs Creek, 23 Jul 1943, F. A. Barkley 13551 (TEX-LL); Onion Creek, 20 Jul 1948, W. V. Brown s.n. (TEX-LL); McKinney Falls, jct. of Onion & Williamson creeks, in marly and sandy soil in pothole in bed of Onion Creek, 5 Jul 1954, Bro. D. Lynch 9460 (SEU); along Onion Creek, 8.5 mi S of Colorado River in Austin, in mud at edge of water, 21 Jul 1964, D. S. Correll & H. B. Correll 29938 (TEX-LL); Wilbarger Creek, 31 Jul 1987, C. W. Sexton s.n. (COA); sandy soil on flats exposed on unshaded strand along Lake Travis at S end of Shaw Rd., Turkey Bend Resource Area, 30 Jul 1991, W. R. Carr & D. Hernandez 11328 (TEX-LL); Slaughter Creek at Kingfisher Creek Lane, 25 Jun 1993, W. R. Carr & P. McNeal 12848 (TEX-LL). Previous Travis County floras: Lynch, 1974. Other reports: Walnut Creek Park (Turner, 1996) and McKinney Falls State Park (Johnston & Riskind, 1975).

Sagittaria graminea Michx. subsp. graminea. GRASSY ARROWHEAD. Native perennial. Apparently rare in our area. No recent reports, but perhaps persistent along Lake Austin.

Specimens: shallow water along edge of Lake Austin, 25 Aug 1945, L. Taylor & F. A. Barkley 14645 (TEX-LL; ann. R. Haynes, 1995). Previous Travis County floras: none. References: Bogin, 1955.

Sagittaria montividensis Cham. & Schlect. subsp. calycina (Engelm.) Bogin. Sagittaria calycina Engelm. ARROWHEAD. Native perennial. Like the preceding, apparently rare in our area but perhaps persistent along Lake Austin.

Specimens: Lake Austin, 29 Nov 1921, B. C. Tharp 1023 (TEX-LL); silt, Lake Austin, fall 1921, B. C. Tharp s.n. (TEX-LL); Austin Lake shore under Mt. Bonnell, 12 Aug 1943, F. A. Barkley 13451 (TEX-LL). All of these TEX-LL specimens were annotated in 1995 by R. Haynes. Previous Travis County floras: none. References: Bogin, 1955.

Sagittaria platyphylla (Engelm.) J. G. Smith. DELTA ARROWHEAD. Native perennial. Apparently the common arrowhead in our area, with specimens from wet soils along Barton Creek, Onion Creek, Shoal Creek, Lake Austin, and various ponds.

Specimens: numerous sheets at TEX-LL, annotated in 1995 by R. Haynes. Previous Travis County floras: Young, 1920; Lynch, 1974. References: Bogin, 1955.

HYDROCHARITACEAE FROG'S-BIT FAMILY

Egeria densa Planch. WATERWEED, EGERIA. Naturalized submersed aquatic; native of South America, widely naturalized in still or slow-moving water in the United States. Similar to Hydrilla verticillata, but in Egeria the leaves have entire margins, lack an elevated midrib on the lower surface, and are smooth to the touch. Said to occur with Hydrilla verticillata at Lake Walter E. Long; no voucher seen.

Specimens of most genera of Hydrocharitaceae were on loan from TEX-LL in Mar 1996 and were not examined. Previous Travis County floras: none.

Hydrilla verticillata (L. f.) Caspary. HYDRILLA. Naturalized submersed aquatic; native of the Old World, rapidly becoming naturalized across the southeastern United States where it is considered a serious noxious weed of navigable waterways. A relatively recent introduction to the aquatic flora of central Texas, but by 1975 it was so abundant in the San Marcos River that it was being harvested commercially for sale in the aquarium trade (Flook, 1975). Abundant in Lake Walter E. Long and in portions of Lake Austin.

Specimens: Lake Long, abundant submerged aquatic, inlet at N end of lake, 12 Aug 1988, Bro. D. Lynch, M. Campbell & J. Gee 9855 (SEU); Wells Branch Creek at Walnut Creek Park, 25 Aug 1990, W. R. Carr & J. Wright 10778 (TEX-LL). Specimens of most genera of Hydrocharitaceae were on loan from TEX-LL in Mar 1996 and were not examined. Previous Travis County floras: none. References: Flook, 1975; Solymosy, 1974.

POACEAE (GRAMINEAE) GRASS FAMILY

Aegilops cylindrica Host. Triticum cylindricum (Host.) Ces. JOINTED GOATGRASS. Adventive annual; native of Europe. Rare on disturbed roadsides; perhaps not a persistent member of our flora.

Specimens: Burnet highway 1 mi N of Allandale Village, Austin, 18 Apr 1953, B. C. Tharp 53-822 (TEX-LL); gravelly roadside, R. M. 2222 near Four Points, 3 May 1986, W. R. Carr & E. A. Kutac 7376 (UVST). Previous Travis County floras: Brown, 1958.

Agrostis elliottiana Schult. ELLIOTT BENTGRASS. Native annual. Reported from the Colorado River flood plain and Midway Sands (Higdon, 1948).

Specimens: None at TEX-LL, June 1996. Previous Travis County floras: Higdon, 1948; Brown, 1958.

Agrostis hyemalis (Walt.) B.S.P. WINTER BENTGRASS. Native annual. Apparently rare in our area, collected only from alluvial deposits along the Colorado River; to be expected in post oak woodlands.

Specimens: Austin, Colorado River flood plain, 9 Apr 1929, A. Armer 5286 (TEX-LL) and 23 Apr 1929, A. Armer 5311 (TEX-LL); Colorado River, Austin, 30 Apr 1936, B. C. Tharp s.n. (TEX-LL) and 21 Apr 1938, B. C. Tharp s.n. (TEX-LL); Deep Eddy, Austin, 26 Apr 1936, B. C. Tharp 44466 (TEX-LL). Previous Travis County floras: Higdon, 1948; Brown, 1958.

Alopecurus carolinianus Walt. Alopecurus ramosus Poir. CAROLINA FOXTAIL. Native annual. Widespread in North America but apparently rare in our area. The Tharp specimen may have been collected on the Colorado River floodplain, a location from which he collected other specimens on that date. No recent specimens or reports.

Specimens: Catholic Cemetery, 2 Apr 1901, Long s.n. (TEX-LL); Austin, 21 Apr 1938, B. C. Tharp s.n. (TEX-LL). Previous Travis County floras: Higdon, 1948; Brown, 1958.

Andropogon gerardii Vitman var. gerardii. Andropogon furcatus Muhl. BIG BLUESTEM. Native perennial. One of the principal components of North American tallgrass prairie communities, and one of the least tolerant of grazing. Uncommon in our area, perhaps most frequently encountered in clay loam over limestone in patches of ungrazed grassland along roadsides and in various nature preserves.

Specimens: Onion Creek, 27 Sep 1941, B. Moon 142 (TEX-LL); Austin, Oct 1941, B. C. Tharp s.n. (TEX-LL); Rosehill Cemetery, Johnson Rd. off Loop 212, 17 Jul 1986, C. W. Sexton, N. McClintock, & K. Bear s.n. (COA); local in clay soils in unmown bar ditch on unshaded W side of North Turnersville Rd., 10 feet N of its jct. with Turnersville Rd., 8 Sep 1990, W. R. Carr & D. A. Brown 10793 (TEX-LL); locally common in live oak savannah on shallow well drained calcareous silty loam over Glen Rose Limestone, E side of R. M. 1826 across from Sharl Drive, 2.0 roadmiles S of Slaughter Creek low water crossing, 26 Jul 1991, W. R. Carr, P. McNeal & M. Enquist 11300 (TAES, TEX-LL); locally common in dry honeycombed Edwards Limestone exposed on low banks and bluffs in bottom of canyon of Bear Creek, at waterfall and upstream in NW corner of Lancaster Tract (a Prop 2 tract), ca. 1.75 airmiles W of jct. F. M. 1626 and Manchaca Rd., 7 Dec 1999, W. R. Carr & S. Windhager 18658 (TEX-LL); occasional patches with little bluestem and Indiangrass in openings in live oak - cedar elm - Ashe juniper woodland on moderately steep, very cobbly Edwards Limestone slope, SE side of drainage running SW to NE across Reavley Tract (a Prop 2 tract), 4.0 airmiles SSE of R. M. 1826 bridge over Slaughter Creek, or 4.1 airmiles E of R. M. 1826 bridge over Bear Creek, 9 May 2000, W. R. Carr 18969 (TEX-LL). Previous Travis County floras: Higdon, 1948; Brown, 1958; Lynch, 1974.

Andropogon glomeratus (Walt.) B.S.P. BUSHY BLUESTEM. Native perennial. Common in moist loamy soils along creeks, in drainage ditches, and along margins of impoundments. According to Campbell (1983), our plants belong in var. pumilis Vasey.

Specimens: Barton Springs, 14 Jan 1913, F. McAllister s.n. (TEX-LL); Barton Creek, 1 Nov 1915, M. S. Young s.n. (TEX-LL); Austin, 4 Nov 1922, R. H. Painter s.n. (TEX-LL); Capt. Aldrich Place, 15 Oct 1934, B. C. Tharp s.n. (TEX-LL); near Lake Travis, 2 mi S of Travis Peak, rather frequent in damp to moist soil, 8 Oct 1948, C. M. Rogers 6529 (TEX-LL); dry bed of Bee Creek W of Lake Austin, 24 Sep 1947, W. V. Brown 3401 (TEX-LL); Watkins Ranch, cypress bog, 8 Oct 1948, Tharp et al. 49036 (TEX-LL); Watkins Ranch, Lake Travis, NW corner of county, 14 Oct 1950, B. C. Tharp et al. 51-497 (TEX-LL). Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958 (as Arthrolepis glomeratus); Lynch, 1974. References: Campbell, 1983.

Andropogon virginicus L. BROOMSEDGE BLUESTEM. Native perennial. Common to abundant in grasslands and open woodlands in moist sandy to loamy soils just to the east but apparently rare within Travis County. Known only from a small population in a seasonally moist area under a power transmission line at Walnut Creek Metropolitan Park, but to be expected in post oak woodlands in the eastern part of the county. According to Campbell (1983), our plants belong in var. virginicus.

Specimens: None at TEX-LL, May 1996. Previous Travis County floras: none. Other reports: Walnut Creek Metropolitan Park (P. Turner, 1996). References: Campbell, 1983.

Aristida oligantha Michx. OLDFIELD THREEAWN. Native annual. A common weed of overgrazed pastures in other parts of the state, but relatively rare in our area where it occurs primarily in early successional or disturbed grasslands on sandy substrates.

Specimens: Golf Links, Austin, Nov 1925, B. C. Tharp 3956 (TEX-LL); Austin, 13 Oct 1928, B. C. Tharp 5123 (TEX-LL); rare in old field grassland on fine sandy loam, S end of Pace Bend Park, 27 Aug 1996, W. R. Carr 15664 (TEX-LL); occasional in grassland on shallow stony noncalcareous clay loam (Crawford and/or Speck series) in openings in Quercus fusiformis woodland on gently rolling upland underlain by Edwards Limestone, on southern (undeveloped) portion of Lady Bird Johnson National Wildflower Center, 10 Nov 2000, W. R. Carr & S. Windhager 19342 (TEX-LL). Previous Travis County floras: Brown, 1958. References: Allred, 1985b.

Aristida longespica Poir. var. longespica. SLIMSPIKE THREEAWN. Native annual. Rare in sandy soils of post oak woodlands.

Specimens: Frequent in well drained, slightly acid, gravelly loamy sand over cherty Pleistocene fluviatile terrace deposits, open post oak woodland/pasture, Farquhar Farms SE of Manor, 22 Nov 1995, W. R. Carr, G. & N. Farquhar 15096 (TEX-LL). Previous Travis County floras: none. References: Allred, 1985a; Allred, 1985b.

/Aristida longespica Poir. var. geniculata (Raf.) Fern. Aristida intermedia Scribn. & Ball. KEARNEY THREEAWN. Native annual. Abundant in disturbed sandy soils in a variety of situations on the coastal plain just east to the east, but apparently rare in our area. Our specimens seem to have come mostly from post oak woodlands on sandy to gravelly river deposits.

Specimens: Dry gravelly soils, Austin, 18 Oct 1920, B. C. Tharp 34 (TEX-LL); Westfield, Austin, 11 Nov 1928, B. C. Tharp 5204 (TEX-LL) and 13 Oct 1938, B. C. Tharp s.n. (TEX-LL). Previous Travis County floras: Brown, 1958 (not as to variety). Other reports: Brackenridge Field Lab (Anonymous, 1979). References: Allred, 1985a; Allred, 1985b.

Aristida purpurascens Poir. ARROWFEATHER THREEAWN. Native perennial. Doubtful in our area, included here solely on the basis of an unvouchered report from the Cortana subdivision (Mase, 1985).

Specimens: None at TEX-LL, May 1996. Previous Travis County floras: none. References: Allred, 1985b.

Aristida purpurea Nutt. var. longiseta (Steud.) Vasey. Aristida longiseta Steud. RED THREEAWN. Native perennial. Common in pastures and early successional grasslands on all substrates.

Specimens: Austin Chalk 10 mi N of Austin on Dessau Farm Rd. 200 yds. E of Dallas Hwy., 13 Jun 1950, Tharp & York 50-135 (TEX-LL); grassland opening on limestone ridgetop, Jester Estates area, 21 Jun 1982, W. R. Carr 4114 (TAES); dry open flat to slightly sloping limestone outcrop, in valley of Barton Creek, ca. 2 mi upstream from Barton Springs at Zilker Park, 0.5 mi NE of Loop 360 bridge, 31 May 1989, S. L. Orzell & E. L. Bridges 10209 (TEX-LL). Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958; Lynch, 1974. References: Allred, 1984; Allred, 1985b.

Aristida purpurea Nutt. var. nealleyi (Vasey) Allred. Incl. Aristida glauca (Nees) Walp. BLUE THREEAWN. Native perennial. Common in grasslands on rocky limestone slopes and uplands.

Specimens: Rocky limestone slope, Bull Creek watershed, 23 Jun 1982, W. R. Carr 4124 (BRIT/SMU); dry rocky clay soil on limestone ridgetop, North Cat Mt., 11 Jul 1982, W. R. Carr 4152 (TAES); dry open flat to slightly sloping limestone outcrop, in valley of Barton Creek, ca. 2 mi upstream from Barton Springs at Zilker Park, 0.5 mi NE of Loop 360 bridge, 31 May 1989, S. L. Orzell & E. L. Bridges 10180 and 10205 (TEX-LL); occasional in grassland on shallow stony noncalcareous clay loam (Crawford and/or Speck series) in openings in Quercus fusiformis woodland on gently rolling upland underlain by Edwards Limestone, on southern (undeveloped) portion of Lady Bird Johnson National Wildflower Center, 10 Nov 2000, W. R. Carr & S. Windhager 19343 (TEX-LL). Previous Travis County floras: Higdon, 1948; Brown, 1958. Other reports: Edwards Plateau Laboratory I (Lynch, 1975). References: Allred, 1984; Allred, 1985b.

Aristida purpurea Nutt. var. purpurea. Incl. Aristida roemeriana Scheele. PURPLE THREEAWN. Native perennial. Common in grasslands, particularly in grazed and early successional areas, on all substrates.

Specimens: Watkins Ranch in NW Travis County above Cow Creek on Lake Travis, 2 Jun 1951, B. C. Tharp et al. 51-932 (TEX-Ll); McKinney Falls State Park, near old mill site by Onion Creek, clay loam and alluvium, 3 Nov 1971, S. Oefinger, Jr. 317 (TEX-LL); rocky limestone slope, Bull Creek watershed, 23 Jun 1982, W. R. Carr 4123 (BRIT/SMU); Austin, Brackenridge Field Station, just W of Firefly Meadow, 22 Jul 1986, S. Ginzbarg 348 (TEX-LL); dry open flat to slightly sloping limestone outcrop, in valley of Barton Creek, ca. 2 mi upstream from Barton Springs at Zilker Park, 0.5 mi NE of Loop 360 bridge, 31 May 1989, S. L. Orzell & E. L. Bridges 10179 (TEX-LL). Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958; Lynch, 1974. References: Allred, 1984; Allred, 1985b.

Aristida purpurea Nutt. var. wrightii (Nash) Allred. Aristida wrightii Nash. WRIGHT THREEAWN. Native perennial. Common in grasslands on rocky limestone slopes and uplands.

Specimens: Gravelly soil, Austin, June 1920, B. C. Tharp 35 (TEX-LL); Walnut Creek, Austin, 20 Oct 1928, B. C. Tharp 5117 (TEX-LL). Previous Travis County floras: Higdon, 1948; Brown, 1958. Other reports: Edwards Plateau Laboratory I (Lynch, 1975). References: Allred, 1984; Allred, 1985b.

Arundo donax L. GIANT CANE. Naturalized perennial, native of the Old World. Relatively recently introduced in the southeastern United States, extensively planted for erosion control along highways. Gould (1975) reported that giant cane plants in Texas apparently don't produce fertile seed; nonetheless the species has escaped cultivation to become a weed of drainage ditches and riverbanks throughout our area.

Specimens: Austin at Red Bud Island, just W of Lake Austin Blvd. on Red Bud Trail, 25 Jul 1990, M. Bierner 90-118 (TEX-LL); Brackenridge Field Laboratory, Austin, 1 Dec 1990, L. K. Escobar 8869 (TEX-LL). Previous Travis County floras: Brown, 1958; Lynch, 1974. References: Cheatham, Johnston & Marshall, 1995.

Avena sativa L. Avena fatua L. var. sativa (L.) Hausskn. WILD OATS. Introduced annual; a crop plant of European origin. Uncommon in our area, mostly in old fields and along disturbed creekbanks, drainage ditches and roadsides.

Specimens: Rare in alluvial thicket, E bank of Shoal Creek between W. 40th and W. 45th Sts., Austin, 16 Apr 1983, W. R. Carr 4686 (TAES); with various weeds in disturbed clay in bed of Waller Creek at Shipe Park, SW corner of W. 45th and Avenue F, Austin, 3 May 1996. W. R. Carr & P. Turner 15253 (TEX-LL). Previous Travis County floras: Higdon, 1948; Brown, 1958; Lynch, 1974.

Bothriochloa barbinodis (Lag.) Herter var. barbinodis. CANE BLUESTEM. Native perennial. A common component of grasslands to the south and west, apparently rare or overlooked in our area.

Specimens: Campus D & D Institute, 10 Sep 1901, A. M. Ferguson s.n. (TEX-LL). Previous Travis County floras: Brown, 1958 (as Amphilophis barbinodis).

Bothriochloa barbinodis (Lag.) Herter var. perforata (Fourn.) Gould. Andropogon perforatus Fourn. PINHOLE BLUESTEM. Native perennial. Rare or overlooked in early successional grasslands on a variety of substrates.

Specimens: Campus, 15 Oct 1908, F. A. Wolf s.n. (TEX-LL); local, one small patch on moderately moist silty clay loam on unmown curblawn shaded by oaks, NE corner of Bailey Lane and W. 39th St., Austin, 14 Jun 1986, W. R. Carr 7576; rare in fairly dry clay soil over limestone in openings in mixed uplands woods, ca. 500 ft. E of MoPac, 0.2-0.4 mi S of Barton Springs Rd. overpass, 26 Jun 1988, W. R. Carr 9006 (BRIT/SMU, TAES). Previous Travis County floras: Higdon, 1948; Brown, 1958 (as Amphilophis perforatus).

Bothriochloa hybrida (Gould) Gould. HYBRID BLUESTEM. Native perennial. Apparently arising from one or more hybrids between Bothriochloa edwardsiana and Bothriochloa laguroides subsp. torreyana (Gould, 1957). According to Gould (1975), found in open pastures and on roadsides, often abundant along mowed roadside ditches. Perhaps more common in our area than specimen records indicate.

Specimens: None at TEX-LL, May 1996. Gould (1957) cited one specimen from Travis County: 20 mi NW of Oak Hill, F. W. Gould 5961 (TAES). Previous Travis County floras: none. References: Gould, 1957.

Bothriochloa ischaemum (L.) Keng var. songarica (Rupr.) Celerier & Harlan. Andropogon ischaemum L. var. songaricus Ruprecht. KING RANCH BLUESTEM. Naturalized perennial. Relatively recently introduced from Asia to Texas, where it has been widely seeded as a forage grass in pastures and for erosion control along highways. Higdon (1948) reported that King Ranch bluestem "shows promise" and "has been introduced into Travis County for study." The results of that study are now in: King Ranch presently ranks among our most noxious weeds, having become thoroughly naturalized in grasslands and open areas on all substrates.

Specimens: Austin, weed in the University of Texas Grass Garden, 15 Nov 1956, W. V. Brown s.n. (TEX-LL); common in old field opening in juniper woodland on limestone upland, Lake Austin City Park, 1 Nov 1981, W. R. Carr 3625 (BRIT/SMU). Previous Travis County floras: Brown, 1958; Lynch, 1974.

Bothriochloa laguroides (DC.) Herter subsp. torreyana (Steud.) Allred & Gould. Bothriochloa saccharoides (Sw.) Rydb. var. torreyana (Steud.) Gould; Andropogon saccharoides of some local auth., in part. SILVER BLUESTEM. Native perennial. A common component of midgrass grasslands, particularly over calcareous strata.

Specimens: 10 sheets at TEX-LL, May 1996. Previous Travis County floras: Brown, 1958 (as Amphilophis saccharoides); Lynch, 1974. References: Allred & Gould, 1983.

Bothriochloa longipaniculata (Gould) Allred & Gould. Bothriochloa saccharoides (Sw.) Rydb. var. longipaniculata (Gould) Gould. Andropogon saccharoides of some local auth., in part. LONGSPIKE SILVER BLUESTEM. Native perennial. Frequent in grasslands over various strata, often with the preceding variety.

Specimens: McDonald Ranch, 1941-1942, D. Higdon 111 (TEX-LL); one block W of Guadalupe in alley off 29th St., dry calcareous soil, 6 Apr 1986, N. Snow 224 (TEX-LL). Previous Travis County floras: Higdon, 1948. Other reports: Edwards Plateau Laboratory I (Lynch, 1975). References: Allred & Gould, 1983.

Bouteloua aristidoides (H.B.K.) Griseb. NEEDLE GRAMA. Native annual. Rare in disturbed sandy soils. A species of the arid west, seldom encountered here at or near the eastern edge of its range.

Specimens: Austin, Nov 1974, G. Edwards s.n. (TEX-LL); loamy fine sand on old Colorado River terrace deposits, seldom used soccer field, level unshaded area on N side of W. First St., 0.3 mi. W of Lamar, Austin, 6 Sep 1991, W. R. Carr & W. C. Bergquist 11381 (TEX-LL). Previous Travis County floras: none.

Bouteloua curtipendula (Michx.) Rydb. SIDEOATS GRAMA. Native perennial. Common in midgrass grasslands over a variety of substrates.

Specimens: Numerous sheets at TEX-LL, May 1996. Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958; Lynch, 1974. References: Gould & Kapadia, 1962a; Gould & Kapadia, 1962b.

Bouteloua gracilis (H.B.K.) Lag. ex Steud. BLUE GRAMA. Native perennial. A common component of short- and midgrass grasslands to the north and west of our area. Doubtful in our area; reports from Travis County need confirmation.

Specimens: None at TEX-LL, May 1996; none at SEU, Jan 1997. Previous Travis County floras: Lynch, 1974.

Bouteloua hirsuta Lag. HAIRY GRAMA. Native perennial. Common in early successional grasslands, perhaps more common in sandy soils but also on shallow clay loam on limestone ridgetops.

Specimens: Campus D & D Institute, 10 Sep 1901, A. M. Ferguson s.n. (TEX-LL); I & GN RR, 12 Oct 1913, M. S. Young s.n. (TEX-LL); McDonald Ranch, 1941-1942, D. Higdon 4 (TEX-LL); infrequent on limestone plateau 12 mi W of Austin, 12 Oct 1945, B. H. Warnock & C. C. Albers 45-70 (TEX-LL); Watkins Ranch, Lake Travis, NW corner of county, 14 Oct 1950, B. C. Tharp et al. 51-501 (TEX-LL); relict grassland, thin soil over limestone, 28 Oct 1954, Bro. D. Lynch s.n. (TEX-LL); in red sandy calcareous clay 4 mi NW of Pedernales River ferry on Marshall Ford Lake, 28 Jul 1946, F. A. Barkley & C. Rowell 57 (TEX-LL); McKinney Falls State Park, W of upper falls about 100-200 ft up hill, 3 Nov 1971, S. Oefinger 310 (TEX-LL). Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958; Lynch, 1974.

Bouteloua pectinata Featherly. Bouteloua hirsuta Lag. var. pectinata (Featherly) Cory; Bouteloua hirsuta Lag. subsp. pectinata (Featherly) J. Wipff & S. D. Jones. TALL GRAMA. Native perennial. Abundant on open rocky limestone slopes, particularly those underlain by Glen Rose Limestone, often in association with Muhlenbergia reverchonii.

Specimens: 9 sheets at TEX-LL, May 1996. Previous Travis County floras: Brown, 1958. Presumably included by Young (1920) and Lynch (1974) within Bouteloua hirsuta.

Bouteloua repens (Kunth) Scribn. & Merr. SLENDER GRAMA. Native perennial. Rare, one record from a degraded Blackland Prairie site. A species primarily of the South Texas Plains; our report would represent the northern limit of its range.

Specimens: Center Union Church cemetery on Houston Black clay, 16 Jul 1987, C. W. Sexton s.n. (COA). No specimens at TEX-LL, May 1996. Previous Travis County floras: none.

Bouteloua rigidiseta (Steud.) Hitchc. var. rigidiseta. TEXAS GRAMA. Native perennial. Common in early successional grasslands and open woodlands on shallow sandy to clayey soils.

Specimens: 16 sheets at TEX-LL, May 1996. Previous Travis County floras: Young, 1920 (as Polyodon texanus Nash): Higdon, 1948; Brown, 1958; Lynch, 1974.

Bouteloua trifida Thurb. Bouteloua trifida S. Wats. RED GRAMA. Native perennial. Frequent in early successional grasslands and open woodlands on shallow sandy to clayey soils.

Specimens: 11 sheets at TEX-LL, May 1996. Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958; Lynch, 1974.

Briza minor L. LITTLE QUAKINGGRASS. Naturalized annual. Frequent in moist sandy soils in disturbed or early successional communities on the Texas Gulf Coastal Plain, but apparently rare in Travis County.

Specimens: Limestone bluff S of Williamson Creek, E of I-35 in SE Austin, juniper woodland, along creek in shade, 25 May 1983, B. Ertter & J. E. Grimes 4849 (TEX-LL). Previous Travis County floras: none.

Bromus catharticus Vahl. Bromus unioloides H.B.K.; Bromus willdenowii Kunth. RESCUEGRASS. Naturalized annual. Native of South America, widely naturalized in southern North America. Common in disturbed situations on all soils, particularly along riparian woodlands and in urban lawns.

Specimens: 10 sheets at TEX-LL, May 1996. Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958; Lynch, 1974.

Bromus diandrus Roth. RIPGUT BROME. Adventive annual. Apparently a rare weed in our area, persistent at the site vouchered below and at several spots along I-35.

Specimens: Abundant in partially shaded vacant lot on loamy urban soils, both sides of Tonkawa Trail at W. 38th St., Austin, 26 Mar 1995, W. R. Carr 14443 (TEX-LL). Previous Travis County floras: Brown, 1958.

Bromus japonicus Murr. Bromus japonicus L. JAPANESE BROME. Naturalized annual. Vernally abundant in grasslands and disturbed sites in all soil types.

Specimens: Austin, 1 May 1938, B. C. Tharp s.n. (TEX-LL); relict grassland plot, Austin clay over Austin chalk, Aristida community, 3 May 1961, Bro. D. Lynch s.n. (TEX-LL); abundant in open field on high creek terrace, E side of Bull Creek SE of jct. Loop 360 and Lakewood Dr., 14 May 1983, W. R. Carr 4870 (TAES). Previous Travis County floras: Higdon, 1948; Brown, 1958; Lynch, 1974.

Bromus pubescens Muhl. Bromus purgans of auth. HAIRY BROME. Native perennial. Occasional in and along margins of mesic woodlands on rocky limestone slopes and on creek and river terraces. The identity of this tall, graceful, seemingly perennial brome is not entirely clear. Wagnon (1952) treated our plants as Bromus nottowayanus Fern., a decision that was not followed by Gould (1975). More problematic is the relationship of Bromus pubescens to Bromus texensis, an endemic annual. Most of our material cannot be determined with certainty.

Specimens: Colorado River bluff, Deep Eddy, 19 Apr 1913, M. S. Young s.n. (TEX-LL); rich moist shaded bluff near Austin, Apr 1921, B. C. Tharp 1069 (TEX-LL); Austin, 17 May 1941, B. C. Tharp 44410 (TEX-LL); floodplain of the Colorado River near Austin, 12 Apr 1946, B. C. Tharp & F. A. Barkley T16128 (TEX-LL); occasional along margin of oak-cedar woods, along vehicle trail N of residences on summit of Cat Mt., ca. 1500 ft. SE of jct. F. M. 2222 and Far West Blvd., W. R. Carr 4743 (TAES, TEX-LL); cedar-oak woods on rocky limestone slope at mouth of ravine, SE side of Bull Creek, SE side of Loop 360 ca. 0.6-0.7 mi NE of Lakewood Dr., 14 May 1983, W. R. Carr 4866 (BRIT/SMU); clay soils over Austin Chalk in riparian woodland above S bank of Tar Branch, Walnut Creek Metropolitan Park, 4 May 1995, P. D. Turner 25 (TEX-LL); locally common in mesic deciduous woodland on alluvial terrace, E bank of Shoal Creek ca. 100 ft. N of W. 29th St. bridge, Austin, 27 Apr 1996, W. R. Carr 15179 (TEX-LL); occasional in mixed evergreen-deciduous riparian woodland or forest strip on narrow alluvial terrace and colluvial slope at foot of limestone bluff, NE bank of Bear Creek downstream from dam just N of house on Tabor Tract (a Prop 2 tract), ca. 3.7-3.8 airmiles SSE of R. M. 1826 bridge over Slaughter Creek, 24 Apr 2000, W. R. Carr 18893 (TEX-LL); rare in mostly deciduous riparian forest along banks of nearly perennial stretch of Bear Creek in canyon between steep limestone walls, E end of Lancaster Tract (a Prop 2 tract) ca. 1.2 airmiles W of jct. R. M. 1626 and Brodie Lane, ca. 0.4 mi upstream from R. M. 1626 bridge, 26 Apr 2000, W. R. Carr 18904 (TEX-LL). Previous Travis County floras: Higdon, 1948; Brown, 1958. References: Wagnon, 1952.

Bromus secalinus L. Incl. Bromus commutatus Schrad., Bromus rigidus Roth. RYE BROME. Adventive annual. Native of the Old World, naturalized in parts of North America. Apparently an uncommon adventive in our area, but reported by Higdon (1948) from all ecological zones of Travis County.

Specimens: Austin, roadside, 4 May 1915, M. S. Young s.n. (TEX-LL); Austin, 9 May 1935, B. C. Tharp s.n. (TEX-LL); waste places, Austin, 29 Apr 1949, W. V. Brown 3515 (TEX-LL); rare in seasonally moist, poorly drained sandy clay loam, weed-dominated community on vacant land ca. 200-300 ft. E of N Lamar Blvd. ca. 1/4 mi N of W. 45th St., Austin, 5 May 1996, W. R. Carr 15290 (TEX-LL). Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958.

Bromus tectorum L. DOWNY BROME. Naturalized annual. Included by Brown (1958) without annotation, perhaps based on records from adjacent counties. To be expected in grazed pastures and mechanically disturbed upland sites.

Specimens: None at TEX-LL, May 1996. Previous Travis County floras: Brown, 1958.

Bromus texensis (Shear) Hitchc. TEXAS BROME. Native annual; a patchily-distributed endemic of the South Texas Plains and Edwards Plateau, with records from Aransas, Bexar, Duval, Goliad, Jim Wells, Karnes, Nueces, San Patricio and Travis counties (Wagnon, 1952; TEX-LL, 2001). Reported by Young (1920) from moist soil on bluffs of the Colorado River; however, her voucher specimen at TEX-LL was anonymously annotated to Bromus pubescens. Reported by Higdon (1948) from Blackland Prairies and the Colorado River floodplain, but no vouchers have come to light. The status of this endemic in our area, and its range-wide taxonomic relationship to Bromus pubescens, merits further study.

Specimens: None at TEX-LL, Nov 2001. Previous Travis County floras: Young, 1920; Higdon, 1948; Lynch, 1974. References: Wagnon, 1952.

Buchloë dactyloides (Nutt.) Engelm. BUFFALOGRASS. Native perennial. One of the dominant species of shortgrass communities in the western half of Texas, common in our area only where mowing or grazing reduces competition from taller grasses and forbs. Recently developed strains are finding increasing acceptance as alternative lawngrasses.

Specimens: 13 sheets at TEX-LL, May 1996. Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958; Lynch, 1974.

Cenchrus spinifex Cav. Cenchrus incertus M. A. Curtis; Cenchrus pauciflorus Benth. SANDBURGRASS. Native annual or short-lived perennial. Locally common in pastures, early successional grasslands and in disturbed sites on sandy soils; rare in clays derived from limestone. Brown (1958) reported an additional sandbur, Cenchrus echinatus L., in his regional grass flora, perhaps on the basis of its occurrence in some adjacent county.

Specimens: University campus, 28 May 1913, M. S. Young s.n. (TEX-LL); sandy soil, field beyond Montopolis bridge, Austin, 4 Jun 1921, B. C. Tharp s.n. (TEX-LL); sandy soil, Colorado River, 2 Jul 1921, B. C. Tharp s.n. (TEX-LL); floodplain, Onion Creek, Austin, 28 Nov 1921, E. A. Allen s.n. (TEX-LL); Austin, 9 Dec 1922, R. H. Painter 22 (SEU); 3610 Windsor Rd., 20 Oct 1948, W. V. Brown s.n. (TEX-LL); on lawn of University of Texas campus, Austin, 15 May 1955, M. C. Johnston & W. L. McCart 530 (TEX-LL); SEU campus, disturbed sandy soil, light shade, 3 Sep 1962, Bro. D. Lynch 9503 (SEU) and 27 Sep 1963, Bro. D. Lynch 9504 (SEU); flood plain at lower end of Town Lake, recently disturbed sandy loam, unshaded, 9 Jul 1969, Bro. D. Lynch 9502 (SEU). Previous Travis County floras: Young, 1920 (as Cenchrus tribuloides); Higdon, 1948; Brown, 1958; Lynch, 1974.

Chasmanthium latifolium (Michx.) Yates. Uniola latifolia Michx. CREEKOATS. Native perennial. Common in alluvial soils in riparian woodlands, usually sharing ground-layer dominance with Elymus virginicus.

Specimens: 9 sheets at TEX-LL, May 1996. Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1959; Lynch, 1974.

Chloris andropogonoides Fourn. Chloris tenuispica Nash. SLIMSPIKE WINDMILLGRASS. Native perennial of South Texas and northern Mexico. Rare in our area, or perhaps simply overlooked. According to Gould, this species hybridizes with Chloris cucullata and Chloris verticillata where their ranges overlap; such plants are presumably referred to Chloris subdolichostachya.

Specimens: University campus, 28 May 1913, M. S. Young s.n. (TEX-LL); Barton Springs, 13 Oct 1941, W. D. Higdon 5 (TEX-LL). Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958. References: Anderson, 1974; Varadarajan & Gilmartin, 1983.

Chloris ciliata Swartz. FRINGED CHLORIS. Perennial, native to various parts of the New World from Texas south to Uruguay (Gould, 1975), but probably adventive in our area. References: Anderson, 1974; Varadarajan & Gilmartin, 1983.

Specimens: Zilker Park, 6 Oct 1957, W. V. Brown s.n. (TEX-LL). Previous Travis County floras: Brown, 1958. References: Anderson, 1974; Varadarajan & Gilmartin, 1983.

Chloris cucullata Bisch. HOODED WINDMILLGRASS. Native perennial. Common in pastures, early successional grasslands and disturbed sites on sandy soils, occasional in clays of limestone uplands.

Specimens: 12 sheets at TEX-LL, May 1996. Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958; Lynch, 1974. References: Anderson, 1974; Brown, 1969; Varadarajan & Gilmartin, 1983.

Chloris pluriflora (Fourn.) Clayt. Trichloris pluriflora Fourn. MANYFLOWERED FALSE-RHODESGRASS. Native perennial. Native of the New World, ranging from South Texas to South America. Frequent on the South Texas Plains, but somewhat anomalous in our area. The one known Travis County site supports other "southern" species, such as Castela erecta subsp. texana, Lycium berlandieri, and Ehretia anacua, for which Travis County may represent the northern limit of present distribution.

Specimens: Below S-facing bluff, N side of Colorado River just W of Loop 360 bridge, 19 Jun 1989, C. W. Sexton s.n. (COA), 1 Oct 1989, W. R. Carr & P. McNeal 10077 (TEX-LL). Previous Travis County floras: Brown, 1958.

Chloris subdolichostachya Muell. Chloris latisquamea Nash. SHORTSPIKE WINDMILLGRASS. Native perennial. According to Gould (1975), Chloris subdolichostachya "is made up largely or possibly entirely of hybrid derivatives of Chloris cucullata X Chloris verticillata crosses and Chloris cucullata X Chloris andropogonoides crosses." Occasional in our area, somewhat weedy in disturbed grasslands and ruderal areas.

Specimens: Waller Creek, 12 Oct 1908, Wolf s.n (TEX-LL); Austin, 22 Nov 1922, R. H. Painter 68 (TEX-LL). Previous Travis County floras: Higdon, 1948; Brown, 1958. Other reports: Walnut Creek Park (P. Turner, 1996). References: Anderson, 1974; Brown, 1969; Varadarajan & Gilmartin, 1983.

Chloris verticillata Nutt. TUMBLE WINDMILLGRASS. Native perennial. Occasional in grasslands on sandy to clayey substrates, particularly in grazed or other early successional areas.

Specimens: McKinney Falls State Park, W of upper falls about 100 ft. up the road, disturbed reek floodplain, gravelly with alluvium, 3 Nov 1971, S. Oefinger Jr. 306 (TEX-LL); site 10 on Shield Ranch, 1 Jul 1982, D. W. Dunlap 96 (TEX-LL). Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958. Other reports: Edwards Plateau Laboratory I (Lynch, 1975); plateau top, Webster Tract, Balcones Canyonlands NWR, 23 Jul 1995, C. W. Sexton s.n. (BCNWR). References: Anderson, 1974; Brown, 1969; Varadarajan & Gilmartin, 1983.

Chloris virgata Sw. SHOWY WINDMILLGRASS. Adventive perennial; native to tropical regions worldwide. Probably introduced into our area as a forage grass and perhaps not a persistent member of our flora.

Specimens: Locally abundant in moderately moist silty clay loam in former pasture on open alluvial terrace, park land on N side of Floral Park Rd. ca. 2 mi W of Jollyville Rd., 6 Dec 1986, W. R. Carr & E. A. Kutac 7969 (TEX-LL); common in dry stony clay and silt on terraces in formerly grazed (?) broad ravine bottom, 1000 ft. NNW of Floral Park & Raining Oaks Drs., 7 Sep 1988, W. R. Carr & M. L. Price 9215. Previous Travis County floras: Brown, 1958. References: Anderson, 1974; Varadarajan & Gilmartin, 1983.

Coelorachis cylindrica (Michx.) Nash. Manisuris cylindrica Michx. CAROLINA JOINTTAIL. Native perennial. Frequent in sandy to loamy soils in grasslands and open woodlands to the east of our area; less common in Travis County, mostly in openings in post oak woodlands on sandy to gravelly Pleistocene terrace deposits or in openings in live oak woodlands on Speck soils over Edwards Limestone.

Specimens: Austin, 1921, B. C. Tharp s.n. (TEX-LL); Park Springs Church cemetery, 29 Jun 1986, C. W. Sexton & M. K. Sexton s.n. (COA); live oak savanna on Speck soils over Edwards Limestone on karstic upland, Edwards 82 Tract (a Prop 2 tract), 8 May 2000, W. R. Carr 18947 (TEX-LL). Previous Travis County floras: none.

Cynodon dactylon (L.) Pers. BERMUDAGRASS. Naturalized perennial; native of tropical and subtropical Africa (Gould, 1975). Cultivated as a lawn and pasture grass, but also thoroughly naturalized as a weed of moist alluvial soils and, less commonly, in disturbed upland situations. As early as the second decade of this century, bermudagrass was "abundant everywhere" in the Austin area (Young, 1920), and this situation has changed little during the intervening decades. The dearth of Travis County specimens at TEX-LL is therefore inexplicable.

Specimens: University campus, 15 Dec 1913, M. S. Young s.n. (TEX-LL); Manor, 11 Oct 1940, B. C. Tharp s.n. (TEX-LL). Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958; Lynch, 1974.

Dactylis glomerata L. ORCHARDGRASS. Adventive perennial; native of temperate parts of the Old World. Introduced as a forage grass in northeastern North America, where it has become naturalized and something of a noxious weed. Apparently rare in our area and perhaps not a persistent member of our flora.

Specimens: Rare, local around pile of refuge on deep loamy soils in wooded valley bottom between limestone ridges, SE side of Loop 360 ca. 0.6 mi NE of Lakewood Dr., 7 May 1983, W. R. Carr 4824 (BRIT/SMU, UVST); rare in moderately moist disturbed clay loam and/or fill on curblawn in "business park" on SW edge of Colorado River terrace, ca. 500 ft. NW of Loop 360 bridge, 1 Mar 1987, W. R. Carr & M. L. Price 7984 (TAES). Previous Travis County floras: none.

Dactyloctenium aegyptium (L.) Beauv. DURBAN CROWFOOTGRASS. Naturalized annual. Rather common in disturbed sandy on the Gulf Coastal Plain of eastern Texas. Uncommon in our area, occurring as a weed of sidewalk cracks and disturbed dry sandy soils.

Specimens: Lakeside bluff, northwestern edge of county, J. B. Watkins Ranch, 29 Jul 1950, B. C. Tharp & C. S. York 50-26 (TEX-LL); disturbed alluvial sands in Colorado River bottom under US Rt. 183 bridges, 2 Oct 1981, W. R. Carr 3448. Previous Travis County floras: Brown, 1958.

Desmazeria rigida (L.) Tutin. Catapodium rigidum (L.) C. E. Hubb.; Scleropoa rigida (L.) Griseb. CATAPODIUM. Naturalized annual. Occasional in clay soils of pastures, in siltier soils on alluvial bars, and in disturbed soils on roadsides.

Specimens: Lake Austin Dam, Austin, 20 May 1939, W. A. Silveus 7027 (TEX-LL) and 5 Jun 1939, W. A. Silveus 7022 (TEX-LL); beneath oaks at Travis Dam, Austin, 29 Apr 1941, B. H. Warnock 21666 (TEX-LL); Austin, 17 May 1944, Innes & Warnock s.n. (TEX-LL); infrequent around hills in limestone soil on Bee Cave Rd. about 10 mi W of Austin, 24 Mar 1946, B. H. Warnock 46049 (TEX-LL); top of bluff at W end of Austin Dam, Austin, 20 Apr 1957, W. V. Brown s.n. (TEX-LL); tight clay among rock rubble in dry bed of Shoal Creek just S of W. 45th St. bridge, Austin, 27 Apr 1983, W. R. Carr 4771 (UVST); abundant in clay in disturbed open area on trail across limestone ridgetop, North Cat Mt., 8 May 1983, W. R. Carr 4851 (BRIT/SMU); sandy gravel over Austin Chalk along Wells Branch in Walnut Creek Metropolitan Park, 19 May 1995, P. D. Turner 28 (TEX-LL); rare in disturbed area around old homesite on summit of a Glen Rose hilltop on Hafif Tract (a Prop 2 tract), ca. 0.65 airmiles S to SSW of R. M. 1826 bridge over Slaughter Creek, ca. 2.25 airmiles S to SSW of jct. R. M. 1826 and US Rt. 290, 19 Apr 2000, W. R. Carr & P. Turner 18863 (TEX-LL); rare in fairly dry sand and gravel on high bar in bed of intermittent creek, Bear Creek just above dam just N of house on Tabor Tract (a Prop 2 tract), ca. 3.6 airmiles S to SSE of R. M. 1826 bridge over Slaughter Creek, 24 Apr 2000, W. R. Carr 18894 (TEX-LL). Previous Travis County floras: Higdon, 1948; Brown, 1958; Lynch, 1974.

Dichanthium annulatum (Forssk.) Stapf. Andropogon annulatus Forssk. KLEBERG BLUESTEM. Introduced perennial; native of tropical and subtropical regions in the Old World (Gould, 1975). Introduced as a forage grass and now a noxious weed in much of the South Texas Plains. Apparently rare in our area, but possibly increasing.

Specimens: On long-deferred severally overgrazed rangeland with scattered Quercus fusiformis and Carya illinoinensis on clay soil over Austin Chalk in Walnut Creek Metropolitan Park, 16 May 1995, P. D. Turner 37 (TEX-LL) and 8 Jul 1995, P. D. Turner 49 (TEX-LL); rare in gravel and silt among limestone rock rubble in frequently flood-scoured bed of Barton Creek, ca. 3/4 mi upstream from Barton Springs Pool, 16 Nov 1996, W. R. Carr, P. McNeal & P. Turner 15854 (TEX-LL); scattered patches in various habitats, N end of Southeast Metro County Park (undeveloped), 10 Nov 1998, Carr, Siegenthaler, Terpening & Chapman 17897 (TEX-LL). Previous Travis County floras: none. Previous Travis County floras: Brown, 1958.

Dichanthium aristatum (Poir.) C. E. Hubb. Andropogon nodosus (Willem.) Nash. ANGLETON BLUESTEM. Introduced perennial; native of subtropical China. Introduced as a forage grass and naturalized as a weed of moist soils of roadside ditches in much of South Texas. Rare in our area, perhaps persistent where seeded.

Specimens: Locally abundant in moderately moist silty clay loam in former pasture on open alluvial terrace, park land on N side of Floral Park Rd. ca. 2 mi W of Jollyville Rd., 6 Dec 1986, W. R. Carr & E. A. Kutac 7967 (TAES, TEX-LL). Previous Travis County floras: none.

Dichanthium sericeum (R. Br.) A. Camus. Andropogon sericeus R. Br. SILKY BLUESTEM. Naturalized perennial. Native of Australia (Gould, 1975); widely planted as a forage grass in South Texas and now naturalized in that region. Two recent collections suggest that the species has potential to become a noxious weed in our area.

Specimens: A few plants in eroding clay on fenceline road/clearing running NNE-SSW through Ulmus crassifolia-Juniperus ashei woodland on steep N-facing slope of Navarro Clay, N end of Southeast Metro County Park (undeveloped), 10 Nov 1998, Carr, Siegenthaler, Terpening & Chapman 17896 (TEX-LL); locally common in disturbed stony clay around unshaded E base of recently constructed hardware superstore, eastward to edge of juniper woodland on limestone upland, N side of Ben White Blvd. between Loop 360 and MoPac, south Austin, 22 May 1999, W. R. Carr & P. Turner 18244 (TEX-LL). Previous Travis County floras: none.

Digitaria californica (Benth.) Henr. Trichachne californica (Benth.) Chase. ARIZONA COTTONTOP. Native perennial. A species of the western United States and northern Mexico, apparently rare in our area. No recent specimens or reports, but likely to occur in small numbers in post oak woodlands on sandy gravelly alluvial terraces. Brown (1958) included two similar species, Digitaria patens (Swallen) Henr. and Digitaria insularis (L.) Mez ex Ekmann, apparently on the basis of their potential occurrence in our area.

Specimens: Austin, 12 Oct 1934, B. C. Tharp 9142 (TEX-LL); Austin, 29 Oct 1942, B. C. Tharp s.n. (TEX-LL); Austin, Tarrytown, 18 Jul 1948, W. V. Brown s.n. (TEX-LL). Previous Travis County floras: Higdon, 1948.

Digitaria ciliaris (Retz.) Koel. Digitaria adscendens (H.B.K.) Henrard. SOUTHERN CRABGRASS. Annual, presumably native to the Old World, now widely naturalized in temperate and tropical America. Frequent in light-textured soils on disturbed alluvial terraces; also a weed of garden beds.

Specimens: N bank S of bridge, 2 Nov 1908, Heald, Wolf & York 427 (TEX-LL); sandy cultivated soil, 0 mi SE of Austin, 2 Jul 1920, B. C. Tharp 26 (TEX-LL); Austin, floodplain, 9 Nov 1922, R. H. Painter 25 (TEX-LL); McDonald Ranch, 1941-1942, D. Higdon 109 (TEX-LL); weed on lawn, Chemistry Building, University of Texas campus, 1 Jan 1955, W. L. McCart 5004 (TEX-LL); disturbed loamy/sandy soil on future home site, limestone ridgetop, North Cat Mt., 11 Jul 1982, W. R. Carr 4150 (TAES); common weed in garden in sandy loam over gravelly/sandy Pleistocene high terrace deposits, Farquhar Farms ca. 5 mi SE of Manor, 16 Jun 1996, W. R. Carr, M. L. Price, C. & N. Farquhar 15535 (TEX-LL); rare in dry silt and sand exposed in bed of Lake Travis during summer of low water level, S end of Sandy Creek Park, 2 Jul 1996, W. R. Carr 15587 (TEX-LL). Previous Travis County floras: none. References: Gould, 1963; Webster, 1987; Webster & Hatch, 1981.

Digitaria cognata (Schult.) Pilger subsp. pubiflora (L. H. Dewey) Wipff. Leptoloma cognatum (Schult.) Chase; Panicum cognatum Schult. FALL WITCHGRASS. Native perennial. Frequent in grasslands and open woodlands on well drained, sandy to clayey soils on uplands and slopes.

Specimens: 17 sheets at TEX-LL, May 1996. Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958; Lynch, 1974.

Digitaria sanguinalis (L.) Scop. Panicum sanguinale L.; Syntherisma sanguinalis (L.) Dulac. HAIRY CRABGRASS. Annual, presumably native of the Old World, now widely naturalized in temperate North America. Apparently an uncommon lawn weed in our area.

Specimens: On lawn, University of Texas campus, 15 May 1955, W. L. McCart 5431 (TEX-LL). Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958; Lynch, 1974. References: Gould, 1963; Webster, 1987.

Echinochloa colona (L.) Link. Echinochloa colonum (L.) Link. JUNGLERICE. Annual, native to Old World tropics, naturalized in much of North America. A weed of moist disturbed soils and cultivated fields.

Specimens: 18 sheets at TEX-LL, Jun 1996. Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958; Lynch, 1974. References: Gould, Ali & Fairbrothers, 1972.

Echinochloa crus-galli (L.) Beauv. BARNYARDGRASS. Naturalized annual. Occasional in clayey soils in creekbeds and other moist disturbed sites. Difficult to distinguish from the next two native taxa.

Specimens: Rare in moist clay and gravel in disturbed creekbed, Far West Blvd. on N side of Cat Mt., 1 Aug 1982, W. R. Carr 4171 (TAES); Lake Long, NE shoreline, occasional along shore and in up to 3 cm of water, 6 Jul 1984, F. R. Barrie 805 (TEX-LL); common in moist clay and clay in partially shaded bed of tributary of Bull Creek ca. 300 ft. S of Floral Park Drive bridge, 9 Sep. 1988, W. R. Carr & D. A. Brown 9234; gravel bar in Walnut Creek Metropolitan Park, 24 Aug 1995, P. D. Turner 150 (TEX-LL). Previous Travis County floras: Higdon, 1948; Brown, 1958; Lynch, 1974. References: Gould, Ali & Fairbrothers, 1972.

Echinochloa crus-pavonis (H.B.K.) Schult. var. macera (Wiegand) Gould. BARNYARDGRASS. Native annual. Occasional in clayey soils in creekbeds and other moist disturbed sites.

Specimens: Austin, 15 Oct 1934, B. C. Tharp 20 (TEX-LL); Colorado River near Austin, 15 Jun 1936, B. C. Tharp 43083 (TEX-LL); base submerged in pond near Barton Springs Creek, 23 Jul 1943, F. A. Barkley 13484 (TEX-LL); seeping area at side of F. M. 969, 6.5 mi E of Webberville, near Travis-Bastrop county line, 5 Jun 1967, J. R. Crutchfield 2894 (TEX-LL). Previous Travis County floras: none. References: Gould, Ali & Fairbrothers, 1972.

Echinochloa muricata (Beauv.) Fern. BARNYARDGRASS. Native annual. Occasional in clayey soils in creekbeds and other moist disturbed sites.

Specimens: Silt at water's edge, Bee Creek ravine, Austin, 2 Aug 1920, B. C. Tharp 21 (TEX-LL); Onion Creek, 27 Sep 1941, B. Moon 135 (TEX-LL); common in wet much along unshaded margin of lagoons at Hornsby Bend Sewage Treatment Plant, 25 Oct 1986, W. R. Carr & E. A. Kutac 7927 (BRIT/SMU); common along creek drainages in Walnut Creek Metropolitan Park, 10 Jul 1995, P. D. Turner 118 (TEX-LL). Previous Travis County floras: none. References: Gould, Ali & Fairbrothers, 1972.

Echinochloa walteri (Pursh) Heller. WALTER BARNYARDGRASS. Native annual. Rare in moist clayey soils along banks of the Colorado River.

Specimens: Below sewage plant, Austin, 28 May 1921, B. C. Tharp 1291 (TEX-LL); Austin, 7 Jul 1921, B. C. Tharp 38 (TEX-LL); common in wet clay on bank of Colorado River at Hornsby Bend Sewage Treatment Plant, 28 Aug 1988, W. R. Carr & M. L. Price 9189 (UVST); rare in wet clay on unshaded N bank of Colorado River at Precinct 1 Park, 1 Sep 1988, W. R. Carr & D. A. Brown 9193 (TAES). Previous Travis County floras: Higdon, 1948; Lynch, 1974. References: Gould, Ali & Fairbrothers, 1972.

Eleusine indica (L.) Gaertn. GOOSEGRASS. Naturalize annual; native of Eurasia, naturalized in much of the New World. Occasional in disturbed situations, perhaps most conspicuous as a weed of sidewalk cracks.

Specimens: Deep Eddy, Austin, 10 Oct 1908, Heald & Wolf s.n. (TEX-LL); Austin, 29 Oct 1941, W. D. Higdon s.n. (TEX-LL); black prairie, Payton farm, 7 mi N of Austin, 13 Oct 1944, R. B. Payton 7 (TEX-LL). Previous Travis County floras: Young, 1920; Higdon, 1948; Brown, 1958.

Elymus canadensis L. CANADA WILDRYE. Elymus villosus Muhl. Native perennial. Frequent in late successional mid- to tallgrass grasslands, perhaps more common along margins of upland live oak woodlands. Most of our plants belong to var. canadensis, but Brown (1958) indicated that var. interruptus (Buckl.) Church also occurs in the a