Carex novae-angliae Schwein.
New England Sedge
Basis for Listing
Carex novae-angliae (New England sedge) went undiscovered in Minnesota until 2001, when it was found in a moist conifer-hardwood forest by the Minnesota Biological Survey. The fact that it was discovered so late in the botanical history of Minnesota is probably a good indication of its rarity.
Carex novae-angliae is not uncommon in parts of eastern North America, but it becomes increasingly rare and disjunct in the western portion of its range including Michigan, Wisconsin, Minnesota, and adjacent portions of Ontario (Shackleford 2004).
Since the time of its discovery in Minnesota, there has been an exceptional effort to find more sites of this elusive species. Ultimately, several new sites were found but all within a relatively small geographic area in the Arrowhead region of the state (Northern Superior Uplands). All of the known sites are on public lands that are actively managed for timber production. This provides an excellent opportunity to incorporate the needs of a rare component of Minnesota’s flora into forest management plans. Without special consideration and careful monitoring, this species could decline significantly.
Given the small number of documented populations, the small size and restricted range of those populations, the current threats posed by competing land use practices, and the vulnerability of known populations to habitat loss and degradation, C. novae-angliae was listed as threatened in 2013.
The appearance and growth form of C. novae-angliae is similar to that of common forest sedges such as C. disperma (shortleaf sedge) and C. brunnescens (brownish sedge). The culms are loosely cespitose, 10-30 cm (4-12 in.) tall; the bases of the culms (remnants of old leaf sheaths) are reddish brown or purplish and weakly fibrous; the rhizomes are at or near the surface of the ground and grow laterally to a length of about 10 cm (4 in.); the leaves are up to 1.7 mm (0.7 in.) wide, about equaling in length or slightly exceeding the longest culms; the terminal spike is staminate, 4-10 mm (0.16-0.40 in.) long, with a peduncle 2-5 mm (0.08-0.2 in.) in length; the lateral spikes are pistillate, 2-3 per culm, the uppermost often overlapping the base of the staminate spike, the lowermost is 1.5-3.0 cm (0.6-1.2 in.) long and rather separate from the other spikes; the pistillate scales have a short scabrous awn and are slightly shorter than the perigynia; the perigynia are moderately to sparsely hairy on the distal third, 2.3-3.0 mm (0.09-0.12 in.) long, 0.7-1.0 mm (0.03-0.04 in.) wide, with a beak 0.3-0.7 mm (0.01-0.03 in.) long; the body (exclusive of beak and stipe) is ellipsoidal in shape (Crins and Rettig 2002). An unusual feature of the perigynia is their transparent nature. This allows the dark achenes inside to be easily seen.
In Minnesota, C. novae-angliae occurs in moist upland forests, typically with a mix of common conifer and hardwood trees including Populus tremuloides (quaking aspen), Betula spp. (paper birch or heartleaf birch), Picea glauca (white spruce), and possibly scattered Pinus strobus (white pine). The shrub layer might have typical species such as Alnus incana subsp. rugosa (speckled alder), Corylus cornuta (beaked hazel), and Acer spicatum (mountain maple). The best habitats may be along a wetland/upland ecotone. Soils are usually loamy, with a large component of organic material. Carex novae-angliae is usually in full to partial shade. While forests of this type are occasionally subjected to wildfire, they are not considered fire-dependent (Minnesota Department of Natural Resources 2003). Carex novae-angliae often occurs with other sedges such as C. disperma, C. brunnescens (both are superficial look-alikes), and C. intumescens (greater bladder sedge).
The forest type favored by C. novae-angliae (as described above) is not particularly unusual in northeastern Minnesota; so there are no obvious features that make the habitat of C. novae-angliae stand out from other habitats.
Biology / Life History
Carex novae-angliae is a perennial wind-pollinated sedge that is adapted to completing its life-cycle in the shade of forest trees. Seeds are likely dispersed short distances by gravity and small animals, possibly including ants (Shackleford 2004). Seeds of C. novae-angliae likely require a season of cold stratification and most probably germinate the year following maturity (Schütz 2000). A study conducted in a mesic old-growth deciduous forest in Quebec, Canada, reported finding dormant seeds of C. novae-angliae in the soil, which might indicate a persistent seed bank (Leckie et al. 2000). Such a seed bank would not be unexpected, since most temperate climate woodland sedges are believed to bank seeds (Schütz 2000). New plants are formed by seed and by the growth of rhizomes from existing plants (Gleason and Cronquist 1991). The rhizomatous growth of C. novae-angliae can result in colonies or clones of genetically identical plants. Although the genetic diversity of Minnesota populations is unknown, it is not likely critical to conservation efforts.
Conservation / Management
Carex novae-angliae develops roots in the upper layer of moist loamy soils, where organic material is a major component. This may make C. novae-angliae vulnerable to the effects of exotic earthworms, which notoriously feed on organic material in the soil. The fragile nature of the soil as well as the need for shade make C. novae-angliae susceptible to some forest management activities (Reznicek and Crins 1993). In particular, soil desiccation can result if the tree canopy is removed. Compaction of the soil by heavy machinery is also a concern. It should also be noted that logging provides an avenue for the invasion of non-native plant species, which could result in increased competition for which C. novae-angliae is not adapted (Reznicek and Crins 1993).
Best Time to Search
For best results, searches for C. novae-angliae should be conducted when perigynia are mature, which will facilitate identification. This is usually from around the middle of June through the middle of July.
Welby R. Smith (MNDNR), 2018
(Note: all content ©MNDNR)
References and Additional Information
Crins, W. J., and J. H. Rettig. 2002. Carex. Pages 254-572 in Flora of North America Editorial Committee, editors. Flora of North America north of Mexico. Volume 23. Oxford University Press, New York, New York.
Gleason, H. A., and A. Cronquist. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. Second Edition. New York Botanical Garden, Bronx, New York. 910 pp.
Leckie, S., M. Vellend, G. Bell, M. J. Waterway, and M. J. Lechowicz. 2000. The seed bank in an old-growth, temperate deciduous forest. Canadian Journal of Botany 78:181-192.
Michigan Natural Features Inventory. 2007. Rare Species Explorer [web application]. Michigan Natural Features Inventory, Lansing, Michigan.
Minnesota Department of Natural Resources. 2003. Field guide to the native plant communities of Minnesota: the Laurentian mixed forest province. Ecological Land Classification Program, Minnesota County Biological Survey, and Natural Heritage and Nongame Research Program. Minnesota Department of Natural Resources, St. Paul, Minnesota. 352 pp.
NatureServe. 2009. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia.
Reznicek. A. A., and W. J. Crins. 1993. Carex novae-angliae (New England sedge) in Michigan: overall review and management recommendations. Hiawatha National Forest, U.S. Forest Service, Marquette, Michigan.
Schutz, W. 2000. Ecology of seed dormancy and germination in sedges (Carex). Perspectives in Plant Ecology, Evolution and Systematics 3(1):67-89.
Shackleford, R. 2004. Conservation assessment for New England sedge (Carex novae-angliae Schwein). USDA Forest Service, Eastern Region, Hiawatha National Forest. <http://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fsm91_054357.pdf>.
Smith, W. R. 2018. Sedges and rushes of Minnesota: the complete guide to species identification. University of Minnesota Press, Minneapolis. 696 pp.
United States Forest Service (USFS). 2006. Regional forester sensitive plants. United States Forest Service, Eastern Region (Region 9), Milwaukee, Wisconsin. 21 pp.