ELEMENT STEWARDSHIP ABSTRACT FOR CAREX LEPTONERVIA July 1, 1994 Stewardship Abstract No.: 020 By: Elizabeth M. Obee State of New Jersey Department of Environmental Protection Division of Parks and Forestry Office of Natural Lands Management CN 404 Trenton, New Jersey 08625 Element Stewardship Abstract Element Stewardship Abstracts (ESA's) are prepared to provide land managers and other conservation workers with current biological and management related information on those species and natural ecosystems that are most important to protect or for which control is most needed. The abstracts organize and summarize data from numerous sources, including the literature and from researchers and managers actively working with the species or ecosystem. The ESA format was originally developed by The Nature Conservancy as a starting point for the stewardship of the many species and ecosystems, or elements, protected by the Conservancy. The New Jersey Office of Natural Lands Management is developing ESA's for those elements that are of particular importance as components of the biota of the state. This includes globally rare plant species that are also listed on New Jersey's official Endangered Plant Species List. The ESA serves several important functions. It helps to identify information gaps and target future research efforts. It provides a standard format for highlighting specific information about a species or community including its management needs. It also allows information to be readily communicated among various preserves, state offices, regional centers, natural heritage programs and private organizations. The ESA is a dynamic document that is continuously updated as new information becomes available. Users are encouraged to contribute their information to the abstract. This sharing of information will benefit all land managers by ensuring the availability of up-to-date information on management techniques and knowledgeable contacts. Please contact the Office of Natural Lands Management for an ESA publication list. It will contain the date of the latest revision to each ESA. Please refer to the abstract number when ordering ESA's. The abstract is a compilation of available information and is not an endorsement of particular practices or products. Element Name: CAREX LEPTONERVIA (Fern.) Fern. Element Code: PMCYP037F0 Preparer: Elizabeth M. Obee Common Name: Finely-Nerved Sedge Description: Habit: Slender tufted deep green perennial. Stems: Retrosely scabrous, rarely almost smooth. Fertile culms 1.5-7 dm. Leaves: Basal leaves 0.5-1 cm wide, and cauline leaves narrow and short the widest 2.5-6 mm. Outer basal sheaths dark purplish brown but soon withering away. Sheaths with erose-scabrous angles. Inflorescence: Terminal spike staminate, with upper spikes often aggregated. Staminate spike not large, often partially hidden by the pistillate spike of 1-3 cm long, alternately to rather densely flowered, the rachis smooth, scales often tinged with color. Pistillate spikes linear-cylindrical, loosely flowered, 1-2.5 cm long, the 2 or 3 upper spikes crowded at the base of the staminate spike. The pistillate scales are occasionally obtuse, with some short-awned. The second pistillate bract often extending over all the spikes. Edges of bract sheaths are usually strongly but minutely serrulate. Perigynia: Obscurely 15-21 nerved, ellipsoidal, 2.5-4 mm long, 2-ribbed, thin and fragile walled, apex slender, acute or beak- like. Roots: Short or slightly elongate, fibrous, with occasional short rhizomes. Distinctions from Related Species: Very similar to other members of the section Laxiflorae, especially C. laxiflora, which occurs in similar habitats. Microscopic examination of the inflorescence is necessary to distinguish this species from others. One distinguishing feature is that it has an obtuse angled perigynia which is nearly to completely nerveless, while most of the other Laxiflorae are strongly nerved (Fernald, 1914). The taxonomy is somewhat confused with reference to the name C. varians, which was used earlier than C. leptonervia (Mackenzie, 1935). However, herbarium specimens labelled C. varians consist of plants of C. blanda and C. ormostachya as well as C. leptonervia (Bryson, 1980). C. leptonervia has been referred to in the literature by a variety of names, including C. blanda var. varians, C. laxiflora var. leptonervia, C. laxiflora var. intermedia, C. laxiflora var. patulifolia, and C. anceps (Burnham, 1919; Fernald, 1914; Wiegand, 1922). Habitat: In the southern portion of its range, C. leptonervia, occurs in moist habitats with conifers or deciduous trees such as Betula or Populus. In the northern portion of its range, it often occurs with Acer saccharum and Quercus rubra in drier, relatively warm conditions (Ball, 1990). Although the species usually occurs in rich deciduous, mixed or hemlock woods it occasionally occurs in cedar swamps and bogs. It thrives in disturbed areas and clearings and in shrub borders of bogs. The range extends from Newfoundland and Quebec to Minnesota, south to New Jersey and Ohio and in the mountains into North Carolina, Tennessee, Virginia and South Carolina at mid to high elevations in moist woods and balds (Fernald, 1906). It is common throughout most of its range, including parts of New York, Vermont, Maine, Michigan, Pennsylvania, Minnesota and Ohio. It is less common in West Virginia, North Carolina, Indiana, Virginia and New Jersey, and is historically known in Kentucky at two locations. In Quebec, it grows in moist Acer forests or scrub forests south of 49 degrees north, and on gravelly shorelines further north (Rousseau, 1974). More than 50 extant occurrences exist (Gagnon, pers. comm.). It is a fairly common sedge in southern and central Ontario with over 100 extant occurrences. In Indiana there are six extant and one extirpated populations (Indiana Natural Heritage Data Center, 1993). At the extirpated site, C. leptonervia was once located at the north border of a swamp in a ravine with Acer saccharum, Equisetum arvense, Podophyllum peltatum, and Carex laxiculmis. The remaining beech- maple (Acer rubrum) swamp sites occur on silt-clay soils. Associated species along a bike trail and railroad track include C. amphibola, C. crinita, Rubus idaeus, and Poa compressa. In Massachusetts it is extant or historical in 9 counties. It does not occur on Cape Cod, although some individuals of C. laxiflora from this area have been mistakenly identified as C. leptonervia (Svenson, 1970). In Tennessee it is documented from 6 counties in the Blue Ridge and one in the Cumberlands physiographic provinces. Its occurrence in the Appalachians is in association with damp conifer forests with few hardwoods, seepage areas, or along old roads and paths (Bryson, 1980). It is found in damp or mucky soils along with Sphagnum, other bryophytes and herbaceous plants. In New Jersey there are only 2 extant occurrences on roadsides with a total of less than 25 known plants. There are an additional 4 historical, potentially extant locations (New Jersey Natural Heritage Program, 1993). C. leptonervia occurs within the Deleware Water Gap National Recreation Area on a rocky hemlock slope in leafy, humus-rich soil, between boulders and in a relatively flat area. Surrounding suitable habitat did not support the plant. Associated species were hemlock, striped maple, basswood, and a heavy growth of ferns; including Dryopteris marginalis, D. intermedia, D. spinulosa, Adiantum pedatum, and Thelypteris hexagonoptera. The other population, last observed in 1979, is on state owned land within Stokes State Forest. Biology/Ecology: The Laxiflorae section is composed of 20 species occurring mainly in the wooded areas of eastern North America (Bryson, 1980). Flavonoid data indicate that the genera are comprised of two distinct groups, one with flavones, and C-glycosyl flavones, and the other with flavonols in addition to the former compounds (Manhart, 1986). C. leptonervia is in the first group, along with C. albursina, C. blanda, C. crebriflora, C. hendersonii, C. gracilescens, C. purpurifera, C. ormostachya, C. styloflexa and C. laxiflora (Manhart, 1986). C. leptonervia fruits from late May to July. Peak flowering in the Appalachians is about a month or two later than species in the valleys or gorges (Bryson, 1980). Populations observed at 4000 feet at Smoky Mountain National Park were flowering in the second week in May in one year, and just beginning to set fruit in another year (Bryson, 1980). In contrast, other sedges such as C. austro-caroliniana, C. laxiflora, and C. plantaginea had already set fruit. One location in Indiana which was surveyed for C. leptonervia was described as second growth flatwoods, hydromesophytic forest with groundwater saturated soils. Associated species at this site were Acer rubrum, Fraxinus pennsylvanica, Liriodendron tulipifera, Quercus alba, Q. rubra, Symplocarpus foetidus, Parthenocissus quinquefolia, Arisaema atrorubens, Lindera benzoin, Maianthemum canadense and Smilacina racemosa. A survey for C. leptonervia at this site revealed 81 genets in 20 1m2 plots centered around at least one C. leptonervia with a mean density of 4.1 +/- 4.8 genets/m2. C. leptonervia was stated to be apparently present throughout the community (Indiana Natural Heritage Data Center, 1993). Determination of Element Occurrence (EO) Quality: High quality occurrences would be at protected locations within a larger area with suitable uncolonized habitat. This would allow for the colonization of new habitat as natural succession alters the habitat of an existing population. Many occurrences are on roadsides or trails. These populations may be more vulnerable to mismanagement or alteration of the disturbance regime which is currently maintaining habitat appropriate for the species. Threats: C, leptonervia is not considered threatened across much of its range based upon the number and size of the populations. However, it is considered rare in several states, including New Jersey, West Virginia, North Carolina, Ohio and Indiana. Most of these areas are on the edge of the species' range. Land Protection Specifications: Several locations of C. leptonervia are protected within state or federal property such as the Indiana Dunes National Lakeshore and the Smoky Mountain National Park. Protection of populations from development and from elimination by succession may need to be implemented if evidence arises that the species' range or total population is declining. Recovery Potential: Recovery potential is unknown, but is presumed to be good given that the species does well in disturbed areas and on roadsides. Biological Monitoring Needs: Sedges in the Laxiflorae are very difficult to distinguish. This raises the probability that C. leptonervia may sometimes be overlooked or misidentified. It may occur in the same areas as C. blanda and C. laxiflora. In southwestern Ontario it also resembles the rarer C. gracilescens. More thorough surveys may reveal that this sedge is either more common or more rare than currently believed. Additional surveys of areas with suitable habitat are needed. Biological Monitoring Procedures: Monitoring should record the number and size of individuals and the proportion of culms flowering. The size of individual genets should give an indication as to their age, but size is probably a more significant parameter of fitness than age. The successional stage of the surrounding community should also be tracked. If any intentional or unintentional manipulation of a population area occurs, the effects of the manipulation should be monitored and recorded. Biological Monitoring Programs: There are no known biological monitoring programs in place that focus upon this species. It is intermittently monitored during surveys of the community composition of various natural areas. However, the need for monitoring is probably not great at most populations since the species is still globally secure. Research Needs: The genus Carex is a very large genus with about 2000 species of herbaceous perennials in a wide range of habitats. A review by Bernard (1990) discussed trends in life history and vegetative reproduction in Carex species. Several suggestions were made for research needs on members of this genus. These include studies of the development of genets, function of tiller clumps, the role of emergence of shoots, and the mechanisms of mortality under different conditions. Much of the research that has been done on Carex species has been taxonomic, where a variety of chemical characteristics have been used to establish species boundaries (Manhart, 1990). Management Needs: Management for C. leptonervia is probably best accomplished by the protection of large tracts of land to be managed at the ecosystem level. Natural disturbance regimes should then be sufficient to maintain populations of C. leptonervia. If populations are declining, management in the form of controlled disturbance may be necessary. Extant populations should have maintenance scheduled in the late summer when it will not interfere with seed dispersal. This is often a problem for roadside populations which are mowed frequently during the summer. Most good roadside habitat is in areas which are infrequently maintained. Summary of Stewardship Needs: C. leptonervia is a relatively common member of the Laxiflorae which occupies a diverse set of woodland habitats, often colonizing disturbed areas. Identification of this and other sedge species can be difficult. This has resulted at times in uncertainty about the frequency of occurrence of this species. More thorough surveys of sedge species and studies of their life history strategies are needed before threats to the species can be adequately assessed. Bibliography for Carex leptonervia (Fern.) Fern.: Ball, P.W. 1990. Some aspects of the phytogeography of Carex. Can. J. Bot. 68: 1462-1472. Bernard, J.M. 1990. Life history and vegetative reproduction in Carex. Can. J. Bot. 68: 1441-1448. Bryson, C.T. 1980. A revision of the North American Carex section Laxiflorae (Cyperaceae). Ph.D. Thesis, Mississippi State University. Burnham, S.H. 1919. The sedges of the Lake George flora. Torreya 19: 125-236. Fernald, M.L. 1906. Some new or little known Cyperaceae of Eastern North America. Rhodora 8: 181-182. Fernald, M.L. 1914. Carex leptonervia a valid species. Rhodora 16: 213-214. Indiana Natural Heritage Data Center. 1993. Element occurrence records for Carex leptonervia. Indiana Natural Heritage Data Center, Indianapolis, Indiana. Mackenzie, K.K. 1935. Cyperaceae, tribe, Cariceae. N. Am. Flora. 18: 169-178. Manhart, J.R. 1986. Foliar flavonoids of the North American members of the Carex Section Laxiflorae (Cyperaceae). Biochem. Syst. Ecol. 14: 85-90. Manhart, J.R. 1990. Chemotaxonomy of the genus Carex (Cyperaceae). Can. J. Bot. 68: 1457-1461. New Jersey Natural Heritage Program. 1993. Element occurrence records for Carex leptonervia. New Jersey Natural Heritage Program, Trenton, New Jersey. Rousseau, C. 1974. Geographie floristique du Quebec-Labrador. Les Presses De L'Universite Laval, Quebec. Svenson, H.K. 1970. Western Cape Cod: Plant notes. Rhodora 72: 1- 9. Wiegand, K.M. 1922. Carex laxiflora and its relatives. Rhodora 24: 189-201.