Vascular Plants of North Carolina
Account for Shaved Sedge - Carex tonsa   (Fernald) Bicknell
Members of Cyperaceae:
Members of Carex with account distribution info or public map:
Google Images
Section 5 » Family Cyperaceae
Show/Hide Synonym
Author(Fernald) Bicknell
DistributionSo far reported from 3 disjunct areas: upper northern Piedmont and northern Mountains, southwestern Mountains (?), and Sandhills and Wake County (?). No doubt more widespread than records indicate, as it is easily overlooked or misidentified. In 2016 Derick Poindexter annotated all specimens of this species group at NCU herbarium; they represent Alleghany, Avery, Cumberland, Hoke, McDowell, Moore, Stokes, and Wilkes counties. Specimens at the SERNEC database from other herbaria are from Ashe, Caldwell, Cherokee, Macon, Richmond, Scotland, Surry, Wake, and Yadkin counties; they need to be double-checked for ID.

Que. to Alb. south to SC, TN, IN, and WI.
AbundanceApparently uncommon, but probably overlooked. Perhaps fairly common in the northwestern corner of the state. The website editors suggest an S3 State Rank.
HabitatDry to xeric rock outcrops, sandhills, sunny woodland ridges, dry roadbanks; soils acidic.
PhenologyFlowering and fruiting April-July.
IdentificationIn the field it appears as a small tuft of fairly broad leaves with flowering stems usually hidden within, and therefore often passed by. It is very close to C. umbellata but differs in its longer perigynia (3.1-4.7 mm vs. 2.2-3.2 mm). From C. rugosperma, it is told by the leaves smooth on the upper surface (vs. roughened).
Taxonomic CommentsA synonym is C. umbellata var. tonsa.

The genus Carex is the largest in North America, and among the largest in the world. In temperate and boreal regions, Carex is often the dominant or co-dominant ground layer in many habitats. Seeds (achenes) are valuable food for birds and small mammals, while foliage is used by birds and mammals to make nests and as food by mammals. Species of Carex often look vastly different from one another -- spikes erect vs. drooping, tiny inflorescence vs. whopping, culms leafy vs. naked, perigynia beaked vs. beakless, stems densely bunched vs. single, etc. The genus has been divided into many sections (or groups), based on shared characters; some taxonomists have suggested that these be different genera, but that proves unworkable (so far). All Carex share the feature of a perigynium (an outer covering) which completely surrounds the achene (seed). This covering may fit tightly or loosely (like a small bladder), depending on which group or species. Details of perigynia shape, ornamentation, presence and size of beak, number of striations (or veins) are all important ID features. In recent years Rob Naczi and colleagues have stressed the importance of arrangement of perigynia -- whether spiral (3+ ranks) or distichous (2-ranked) -- and have named a number of new species as well as split off some older synonyms. Therefore, RAB's (1968) key, excellent for its time, can only be used in a general way today. Members of some sections of Carex are difficult to key out (notably Ovales, Laxiflorae, Griseae); this is in part due to variation among individuals of a species, or failings of the key. FNA has drawings of most species and some species may be found in two or more places within a key, to acount for variability. New species to NC, and new to science(!), continue to be found in NC.
Other Common Name(s)None
State Rank[S3]
Global RankG5
State Status
US Status
USACE-agcp
USACE-emp
County Map - click on a county to view source of record.
Select a source
AllHerbaria
Select an occurrence type
AllCollection_natural