keys to the vascular plants of east texas - Botanical Research ...

544 CYPERACEAE/CAREX
acidic-neutral to calcareous soils; throughout most of East TX, but rare in the sw part, though
reported from Gonzales and Hays cos.; also present in the ne part of the Gulf Prairies and
Marshes; se Canada and e U.S. w to WI, NE, and TX. Fruiting Apr–Oct. Section Lupulinae m/281
Carex lurida Wahlenb., (sallow, pale yellow), SALLOW CARIC SEDGE. A facultative heliophyte in
open swales and open swamps; throughout the Pineywoods, most of the Red River drainage,
most of the Post Oak Savannah except the sw part, rare in the Blackland Prairie, and apparently
absent in the sw part of East TX; also Denton Co. of the Cross Timbers and Prairies; e Canada
and e U.S. w to WI, MO, OK, and TX. Fruiting late Apr–early Jul(–Aug). Section Vesicariae m/281
Carex meadii Dewey, (for its discoverer, Samuel Barnum Mead, 1798–1880, botanist and physician
of CT and IL), SAMUEL MEAD’S CARIC SEDGE. An obligate heliophyte in open mesic to wet
calcareous clay prairies and depressions, and a conspicuous plant in early spring due to its glaucous
leaves; n part of East TX in Dallas, Grayson, Gregg, Kaufman, and Lamar cos., Post Oak
Savannah in Austin and Leon cos., and s part of the Pineywoods in Jasper, Liberty, and San Jacinto
cos.; also n Gulf Prairies and Marshes, Floyd Co. of the High Plains, and Hemphill Co. of
the Rolling Plains; sc Canada and e 1/2 of U.S., also AZ. Fruiting late Mar–mid-May(–early Jun).
Section Paniceae
Carex microdonta Torr. & Hook., (small-toothed), SMALL-TOOTH CARIC SEDGE, LITTLE-TOOTH
CARIC SEDGE. An obligate heliophyte mainly along roadsides but also where basic soils occur,
including calcareous shores, gravels, meadows, prairies, and glades, also possibly in non-calcareous,
neutral soils; throughout the s half of East TX, nw part of East TX, and Red River Co. in
the ne; also e Cross Timbers and Prairies, Wheeler Co. in the Rolling Plains, Edwards Plateau,
Trans-Pecos, and n South TX Plains; sc U.S., also FL. Fruiting late Apr–Jun. Section Granulares
Carex microrhyncha Mack., (small-beaked), SMALL-BEAKED CARIC SEDGE, LITTLE-SNOUT CARIC
SEDGE. A facultative sciophyte that will tolerate some direct sun in submesic oak-hickory forests
or oak-juniper woodlands, found at the base of trees or in semi-open areas with sandy or
sandy gravel soils; throughout much of East TX sw to Bastrop and Lavaca cos., but overlooked
and infrequently collected; also in the Cross Timbers and Prairies in Parker Co. and in the Gulf
Prairies and Marshes in Galveston Co.; AR, KS, MO, OK, and TX. Fruiting early Feb–Apr(–May).
Crins and Rettig (2002) treated this taxon as a synonym of C. umbellata Schkuhr ex Willd.
They stated that “a revision of the C. umbellata-C. tonsa complex may reveal distinctions.” In
fact, preliminary molecular data already support recognition of C. microrhyncha at the species
level (E. Roalson, pers. comm.). In addition, C. umbellata ranges from MO northward while C.
microrhyncha ranges from MO southward. There is also a difference in achene color, and the
achene apex of C. microrhyncha is retuse as opposed to being rounded in C. umbellata. Based on
this information, this taxon is here being recognized at the species rank. Section Acrocystis
Carex muehlenbergii Schkuhr ex Willd., (for Gotthilf Henry Ernest Muhlenberg, 1753–1815, German-educated,
pioneer botanist and Lutheran minister of PA), MUHLENBERG’S CARIC SEDGE. The
following two varieties are distinguished in the key to species. Section Phaestoglochin
var. enervis Boott, (nerveless), GOTTHILF MUHLENBERG’S VEINLESS CARIC SEDGE. An obligate to facultative
sciophyte, but in some habitats growing as a remnant in full sun, in mesic or submesic
hardwood forests (frequently oak-hickory woods), on Alfisols, less frequently on Entisols,
Vertisols, or Histosols, but most frequently found in sandy soils with a humus layer or in thin
soils over limestone with a humus layer; throughout East TX; also Cross Timbers and Prairies,
Edwards Plateau, King Co. in the Rolling Plains, n South TX Plains, and Gulf Prairies and
Marshes from the Coastal Bend area northeastward; se Canada (Ont.) and e U.S. w to WI, NE,
and TX. Fruiting Apr–Jul(–Oct). [C. onusta Mack., C. plana Mack.]
var. muehlenbergii, GOTTHLIF MUHLENBERG’S CARIC SEDGE. Obligate to facultative heliophyte in
Entisols of open sand hills, openings in sandy oak-hickory woods, sandy forest edges, open to