Description
Potentially Misidentified Species - Carex arenaria is also introduced and is a supratidal dune species found in MD-VA (Blake 1934; Brown and Brown 1984). At least 20 native species of Carex have been reported from tidal waters of the Bay (Krauss et al. 1971; Wass 1972; Sipple 1978; Brown and Brown 1984).
Taxonomy
| Kingdom | Phylum | Class | Order | Family | Genus |
|---|---|---|---|---|---|
| Plantae | Magnoliophyta | Liliopsida | Cyperales | Cyperaceae | Carex |
Synonyms
Invasion History
Chesapeake Bay Status
| First Record | Population | Range | Introduction | Residency | Source Region | Native Region | Vectors |
|---|---|---|---|---|---|---|---|
| 1933 | Established | Expanding | Introduced | Regular Resident | Europe | Eurasia | Shipping(Dry Ballast), Agriculture(Agricultural Weed) |
History of Spread
Carex divisa (Divided Sedge) is native to south and central Britain (Stace 1992), southern and western Europe (Tutin et al. 1980), Asia, and Northern Africa (Blake 1934). It was first found in North America along Chesapeake Bay, at Plum Point, Calvert County MD (Blake 1934), and was collected in 1941 along nearby Parker's Creek (U.S. National Herbarium collections). C. divisa was reported from North Neck, Solomons MD (Krauss et al.1971). It was not included in a 1961 VA flora (Massey 1961), but was listed for 3 VA counties bordering the lower Bay (Virginia Beach, York, Gloucester County) by Harvill et al. (1986, 1992).
Fernald (1950) cited only the Calvert County record, but Gleason and Cronquist (1991) gave the range as VA, MD, and NC. Carex divisa has also been introduced to New Zealand and South Africa (Blake 1934).
History References - Blake 1934; Fernald 1950; Gleason and Cronquist 1991; Harvill et al. 1986; Harvill et al. 1992; Krauss et al. 1971; Massey 1961
Invasion Comments
Likely Vector into Chesapeake Bay - C. divisa is not cultivated, or an agricultural or garden weed to our knowledge, so dry ballast is a possible vector. However, the first site of collection was far from any seaport (Blake 1934).
Range Status - Based on its range extension from MD to VA, Carex divisa is apparently spreading slowly.
Ecology
Environmental Tolerances
| For Survival | For Reproduction | |||
|---|---|---|---|---|
| Minimum | Maximum | Minimum | Maximum | |
| Temperature (ºC) | ||||
| Salinity (‰) | 0.0 | |||
| Oxygen | ||||
| pH | ||||
| Salinity Range | meso-poly |
Age and Growth
| Male | Female | |
|---|---|---|
| Minimum Adult Size (mm) | 100.0 | 100.0 |
| Typical Adult Size (mm) | 350.0 | 350.0 |
| Maximum Adult Size (mm) | 600.0 | 600.0 |
| Maximum Longevity (yrs) | ||
| Typical Longevity (yrs |
Reproduction
| Start | Peak | End | |
|---|---|---|---|
| Reproductive Season | |||
| Typical Number of Young Per Reproductive Event |
|||
| Sexuality Mode(s) | |||
| Mode(s) of Asexual Reproduction |
|||
| Fertilization Type(s) | |||
| More than One Reproduction Event per Year |
|||
| Reproductive Startegy | |||
| Egg/Seed Form |
Impacts
Economic Impacts in Chesapeake Bay
Carex divisa (Divided Sedge) is rare and localized in Chesapeake Bay and has no known economic impacts.
Economic Impacts Outside of Chesapeake Bay
Carex divisa (Divided Sedge) is rare and localized in North America and has no known economic impacts.
Ecological Impacts on Chesapeake Native Species
Carex divisa (Divided Sedge) is rare and localized in Chesapeake Bay and has no known impacts on native biota.
Ecological Impacts on Other Chesapeake Non-Native Species
Carex divisa (Divided Sedge) is rare and localized in Chesapeake Bay and has no known impacts on exotic biota.
References
Blake, S. F. (1934) Carex divisa, Teesdalia nudicaulis, and Thlaspi perfoliatum in Maryland, Rhodora 36: 412-414Bronger, Cees; Haugen, Hans Aksel (1983) Vipestarr (Carex extensa Good.) i Norge, Blyttia 41: 143-148
Brown, Melvin L.; Brown, Russell G. (1984) Herbaceous Plants of Maryland, , College Park. Pp.
Fernald, Merritt L. (1950) Gray's Manual of Botany, In: (Eds.) . , New York. Pp.
Gleason, Henry A.; Cronquist, Arthur (1991) Manual of vascular plants of northeastern United States and adjacent Canada, In: (Eds.) . , Bronx, New York. Pp.
Harvill, A. M., Jr.; Bradley, T. R.; Stevens, C. E.; Weiboldt, T.F.; Ware, D.E.; Ogle, D. W. (1986) Atlas of the Virginia Flora, , Farmville, VA. Pp.
Harvill, A. M.; Bradley, Ted R.; Stevens, Charles E.; Wieboldt, Thomas F.; Ware, Donna M. E.; Ogle, Douglas W.; Ramsey, Gwynn W.; Fleming, Gary P. (1992) Atlas of the Virginia Flora, , Burkeville, VA. Pp.
Haslam, S. M. (1972) Biological flora of the British Isles List Br. Vasc. Pl. (1958) No. 665, . 1. Phragmites communis, Journal of Ecology 60: 585-610
Kartesz, John T. (1994) A synonymized checklist of the vascular flora of the United States, Canada, and Greenland., In: (Eds.) . , Portland OR. Pp.
Krauss, R.W.; Brown, R. G.; Rappleye, R. D.; Owens, A. B.; Shearer, C.; Hsiao, E.; Reveal, J. (1971) Checklist of plant species occurring within the hightide limits of the Chesapeake Bay, and its tributaries., , College Park, Maryland. Pp.
Massey, A. B. (1957) Alternanthera in Virginia, Rhodora 59: 239
Massey, A. B. (1961) Virginia flora, an annotated catalog of plant taxa recorded as occuring [sic] in Virginia., Technical Bulletin Virginia Agricultural Experiment Station 155.: 1-258.
Resource Management Inc. (1993) National list of plant species that occur in wetlands., , Minneapolis.. Pp.
Sipple, William S. (1978) An atlas of vascular plant distribution species for tidewater Maryland, , Annapolis, Maryland. Pp.
Stace, C. (1992) New Flora of British Isles, , Cambrdge, UK. Pp.
Tutin, T. G.; Heywood, V. H.; Burges, N.A.; Valentine, D. H.; Walters, S. M.; Webb, D. A. (1964) Flora Europea, , Cambridge UK. Pp.
Tyndall, R. Wayne (1983) Distribution of Cyperus difformis L. (Cyperaceae) in the Southeastern United States, Castanea 48: 277-280