Glaucodea means gray-green (Fernald 1970), which is the color of the leaves and is created by a thin waxy coating on the surface of the leaf blades.
There are six existing populations but more are expected to be found as more people become familiar with the identification of this species. There are 10 historical occurrences.
In the past five years at least five new populations have been found. Most likely these populations have been overlooked in the past. Ten populations are considered historical because they have not been seen in recent years but again this may simply be due to the fact that they have been overlooked recently. Overall short-term trends are not clear.
There is one extant population that has been known for over 120 years. This population is quite healthy and robust. At least two populations are believed to be extirpated. Other information regarding long term trends is not available.
No management needs known.
Carex glaucodea occurs in wet to dry-mesic deciduous forests and old fields. It occurs on the edges of seasonal swamps and in seasonally wet depressions in more open environments. Plants can often be found in roads and deer or human paths through forests. These roads and paths probably are helping the seed bank germinate. Also, these roads and paths often have more compacted soils creating slightly wetter situations preferred by C. glaucodea (New York Natural Heritage Program 2005). Mesic to wet-mesic deciduous forests or seasonally moist prairies, usually in clays or loams (Naczi and Bryson 2002). Dry to moist calcareous woods or fields (Rhoads and Block 2000). Wet woods, swamps, moist fields (Gleason & Cronquist 1991). Calcareous woods and meadows (Fernald 1970).
Carex glaucodea is known mostly from eastern New York (Albany and Rensselaer Counties south to Long Island) but is also known from a couple of sites in central New York.
This sedge occurs from New Hampshire, Massachusetts, and Connecticut west to New York, Ontario, Ohio, and Missouri south to North Carolina, Tennessee, Alabama, Oklahoma, and Texas.
This sedge is a densely tufted grass-like plant with leaves covered with a white waxy covering (glaucous) and up to (5.1-)5.7-10.8 mm wide. Flowering/fruiting stalks (culms) are 10-50 cm tall and contain 3-6 elongated clusters of flowers/fruits (spikes) that are arranged along the culm. Fruits (perigynia) have many fine impressed longitudinal nerves (Naczi and Bryson 2002).
Carex glaucodea has glaucous leaves. The bases of the culms are yellow-brown. The inflorescence consists of one terminal staminate spike which is 7-35 mm long and 2-5 lateral pistillate spikes. The peduncles of the pistillate spikes are smooth. Perigynia are spirally arranged along the axis of the spike, 3.2-4(-4.1) mm long, gradually taper to the apex, have no or only a tiny (0-0.3 mm long) beak, and have 43-54 impressed longitudinal nerves. Pistillate scales are relatively short awned tipped with awns 0-1(-1.5) mm long. Achenes have beaks that are bent (0-)30-90 degrees (Naczi and Bryson 2002).
The glaucous leaves make this Carex a little easier to identify vegetatively although fruits are still necessary to make a positive identification. Mature ample specimens with notes on whether the leaves are glaucous or not are best for identification.
In New York, this species is quite distinctive. There are two other Carex species (C. granularis and C. laxiculmis var. laxiculmis) which look similar vegetatively. Carex granularis has smaller perigynia (2.2-3.1(-3.7) mm long vs. to 3.2-4(-4.1) for C. glaucodea); "nerves" of the perigynia raised (vs. impressed); and beaks of the perigynia, when present, sometimes bent (vs. never bent). Carex laxiculmis has pistillate peduncles flexuous and drooping (vs. stiffer and erect to ascending); 4-9 perigynia per spike (vs. 10-45); and sharply triangular perigynia in cross section (vs. obtusely triangular) (Yatskievych 1999, Naczi and Bryson 2002).
Other members of section Griseae in New York, which C. glaucodea is part of, have green leaves (vs. glaucous) and pistillate scales with longer awns (vs. short or no awns). Awns can occasionally be variable in length. Carex glaucodea is the only member of section Griseae that will appear highly glaucous.
The species is in fruit from June to mid-July. Fruits can sometimes be found on plants later in the season. The best time to survey for this species is mid-June to mid-July.
The time of year you would expect to find Glaucous Sedge fruiting in New York.
Carex glaucodea Tuckerman ex Olney
Carex glaucodea along with C. flaccosperma have been variously treated by many authors. Some authors treat C. glaucodea as a variety of C. flaccosperma (e.g. Fernald 1970), others lump the two together (e.g. Gleason and Cronquist 1991), and others treat the two at the species level. Naczi (1991) shows that the two should be considered distinct at the species level based on morphology, cytology, ecology, geography, and natural hybridization. In addition, Naczi (1997) described a new species C. pigra which is intermediate in perigynia length between C. glaucodea and C. flaccosperma. This may have been part of the reason why some botanists were confused regarding the status of C. glaucodea and C. flaccosperma. In New York, we only have one taxon, C. glaucodea. Carex pigra and C. flaccosperma occur further south and west of New York.
Naczi, R.F.C. and C.T. Bryson. 2002. Carex Linnaeus sect. Griseae (L.H. Bailey) KÃ¼kenthal. Pages 448-461 in Flora of North America Editorial Committee (editors), Flora of North America, north of Mexico, Volume 23, Magnoliophyta: Commelinidae (in part): Cyperaceae. Oxford University Press, New York, NY, USA. 608pp + xxiv.
Fernald, M.L. 1950. Gray's manual of botany. 8th edition. D. Van Nostrand, New York. 1632 pp.
Flora of North America Editorial Committee. 2002. Flora of North America, North of Mexico. Volume 23. Magnoliophyta: Commelinidae (in part): Cyperaceae. Oxford University Press, New York. 608 pp.
Gleason, Henry A. and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York. 910 pp.
Holmgren, Noel. 1998. The Illustrated Companion to Gleason and Cronquist's Manual. Illustrations of the Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York.
Mitchell, Richard S. and Gordon C. Tucker. 1997. Revised Checklist of New York State Plants. Contributions to a Flora of New York State. Checklist IV. Bulletin No. 490. New York State Museum. Albany, NY. 400 pp.
Naczi, R.F.C. 1991. Systematics of Carex flaccosperma and C. glaucodea (section Griseae, Cyperaceae). Supplement to American Journal of Botany 78: 205.
New York Natural Heritage Program. 2010. Biotics database. New York Natural Heritage Program. New York State Department of Environmental Conservation. Albany, NY.
New York Natural Heritage Program. 2020. New York Natural Heritage Program Databases. Albany, NY.
Reschke, Carol. 1990. Ecological communities of New York State. New York Natural Heritage Program, New York State Department of Environmental Conservation. Latham, NY. 96 pp. plus xi.
Rhoads, Ann F. and Timothy A. Block. 2000. The Plants of Pennsylvania, an Illustrated Manual. University of Pennsylvania Press, Philadelphia, PA.
Weldy, T. and D. Werier. 2010. New York flora atlas. [S.M. Landry, K.N. Campbell, and L.D. Mabe (original application development), Florida Center for Community Design and Research http://www.fccdr.usf.edu/. University of South Florida http://www.usf.edu/]. New York Flora Association http://newyork.plantatlas.usf.edu/, Albany, New York
Yatskievych, G. 1999. Steyermark's Flora of Missouri, Volume 1. Revised edition. Missouri Department of Conservation, Jefferson City and Missouri Botanical Garden Press, St. Louis.
Information for this guide was last updated on: June 22, 2005
Please cite this page as:
New York Natural Heritage Program. 2020. Online Conservation Guide for Carex glaucodea. Available from: https://guides.nynhp.org/glaucous-sedge/. Accessed July 9, 2020.