Range and Habitat in Illinois
Regularity: Regularly occurring
Regularity: Regularly occurring
Global Range: A sedge ranging from Vermont and adjacent southern Quebec, west to Wisconsin, and south to Florida, Louisana, and Texas. This sedge is considered rare throughout much of its range, especially northward.
The species is apparently difficult to distinguish at first from the more common Carex lupulina (Jones and Hatch 1990), but becomes increasingly recognizable after several field observations (Reznicek pers. comm.). In the field, C. lupulina appears stockier in form with narrower leaves than C. lupuliformis (Reznicek pers. comm.). When mature, C. lupuliformis can be separated from C. lupulina by its narrower pistillate spikes, spreading perigynia and knobbed achenes (Brant 1987). The knobbed angles on the achenes are the best features used in distinguishing C. lupuliformis from C. lupulina (Reznicek and Ball 1974, Oldham and Crins 1988). The achenes of C. lupuliformis have pointed angles with nipple-like knobs and deeply concave faces, unlike those of C. lupulina, which are neither pointed nor nipple-like and have flat to slightly concave faces (Jones and Hatch 1990). When in any other growth stage than a fruiting adult, however, there are no certain distinguishing features between the two taxa (Crins pers. comm., Reznicek, pers. comm., Reznicek and Ball 1974).
The species tends to be a large plant, with mature individuals apparently never shorter than 50 cm in height in Canada (Reznicek and Ball 1974). Carex lupulina, on the other hand, although sometimes reaching the same height as C. lupuliformis, is more closely aligned with the short end of the spectrum and individuals often do not exceed 20 cm in height (Reznicek and Ball 1974). This dichotomy of C. lupulina occupying the shorter end of the extremes is also apparent in other characters such as leaf width and length, spike number and length, and staminate number and length (Reznicek and Ball 1974).
Bryson (pers. comm.) stated that C. lupuliformis is frequently confused with Carex gigantea. Based on observations from the field in Mississippi, Bryson stated that C. lupuliformis has perigynia poised upward at slight angles from the axis, which persist sometimes until frost, and an overall plant size that is intermediate between the smaller C. lupulina and larger C. gigantea. Carex gigantea, on the other hand, has non-persistent perigynia that extend at right angles from the axis, with the plant usually appearing larger than C. lupuliformis. Plant size, however, in comparison with other species, may change with respect to habitat. This criterion should be used with caution in the field.
Range and Habitat in Illinois
Comments: The range of Carex lupuliformis encompasses an area east of a line from southwestern Quebec, west to Wisconsin and south to Louisiana (Oldham and Crins 1988). In contradiction to published accounts (Oldham and Crins 1988, Hermann 1941), the species does not occur in Minnesota. In no portion of its range is the species common (Reznicek pers. comm., Jones and Hatch 1990).
Reznicek and Ball (1974) stated that the habit of C. lupuliformis is more aquatic than other members of Lupulinae, growing in shallow waters of open marshes and on wet shores. The species is typically a species of river bottoms, frequently occurring in buttonbush (Cephalanthus occidentalis) swamps in knee-deep waters, or in the back-waters of streams possessing heavy soils and subject to severe flooding (Reznicek pers. comm.). When growing in forests, the species is restricted to very wet floodplain forests (Reznicek and Ball 1974) that possess a moderately open canopy (Reznicek pers. comm.).
Individuals of C. lupuliformis tend to do progressively better as canopy becomes more open. This requirement has been reported for nearly every extant population throughout the range of the species (Ontario: Reznicek and Ball 1974; West Virginia: Brant 1987; Delaware: Naczi et al. 1986; New Jersey: Snyder pers. comm.; Mississippi: Bryson pers. comm.). The largest known populations to date (a population of more than fifty plants on the DelMarVa Peninsula in Delaware [Naczi et al. 1986, Naczi pers. comm.] and several populations of 300-400, and up to 1000 individuals in Mississippi [Bryson pers. comm.]) all occur in areas where openings have been artificially developed and maintained through logging and mowing, respectively.
Although possessing exceedingly high numbers of plants in the initial years following logging, clear-cut floodplain forests eventually become poor C. lupuliformis habitat. Floodplain forests, if allowed to develop and mature will, within a few years, produce a thick stand of shrubs and small trees, vastly diminishing the open habitat necessary for the species. Only after many years, when the stand has had enough years to mature, will the successional floodplain environment produce the natural habitat preferred by the species. If left unmown, right-of-way populations would suffer a similar fate.
Carex lupuliformis is believed to be a calciphile by some. River silts, in which the species commonly occurs, are characteristically laden with calcium, possibly meeting the requirements of the species (Reznicek pers. comm.). Plants are found in circumneutral sites in some portions of its range, as in the northeast (Zika pers. comm.) and Ohio (Cusick 1981). In Texas, the species is known historically from calcareous sites, but these tend to be more toward the acidic end of the pH scale than those in other portions of the species' range (Jones pers. comm.). In the south, plants can appear chlorotic in areas that tend to be acidic (Jones pers. comm.), unlike its close relative, C. lupulina, which does well in such habitats. However, in portions of the Atlantic Coastal Plain such as New Jersey (Snyder pers. comm.) and the DelMarVa Peninsula of Delaware (Naczi pers. comm.), the species has been observed in habitats that appear to be acidic in nature.
In the Great Lakes area, C. lupuliformis is typically a species of river bottoms, frequently occurring in the knee-deep waters of buttonbush (Cephalanthus occidentalis) swamps, or in the heavy soils of stream back-waters that are subject to severe flooding (Reznicek pers. comm.) Hermann (1941) listed the species as rare in swampy woods and Cephalanthus swamps south of Saginaw Bay, Michigan, and infrequent northward. When growing in forests, the species is restricted to very wet floodplain forests (Reznicek and Ball 1974) that possess a moderately open canopy (Reznicek pers. comm.). Common associates in the Great Lakes region include buttonbush, silver maple, red maple and red ash (Reznicek pers. comm.).
Cusick (1981) described the habitat of C. lupuliformis in Ohio as a variety of wet or moist situations in shade or semi-shade, often in calcareous or neutral substrates; wet woods, fields, canal beds, stream banks, springs, thickets and shrub borders.
According to Brant (1987), Carex lupuliformis is found in West Virginia in occasionally inundated openings within scrub/shrub emergent marshes along the Meadow River. It is apparently most common in permanently saturated depressions left by past meanders. Floral associates include Carex lupulina, C. tuckermanii, C. typhina, C. squarrosa, C. grayii, C. vesicaria, C. bromoides, C. stricta, C. stipata, Dulichium arundinaceaum, Sparganium eurycarpum, S. americanum, Leersia oryzoides, Panicum rigidulum, Polygonum hydropiperoides, Acer rubrum, Nyssa sylvatica, Rosa palustris, Alnus serrulata and Cephalanthus occidentalis.
The single known extant Ontario site occurs in an open ash-willow floodplain forest along a creek in Essex County, growing with Cephalanthus occidentalis and Carex lupulina (Oldham pers. comm., Oldham and Crins 1988). The area is heavily agriculturalized, with siltation and pollution evident in the stream, but this does not appear to have affected the population (Oldham pers. comm.). A historic southwestern Ontario site visited by Crins (pers. comm.) was characterized as a kettle pond surrounded by meadow in sandy glacial till. Associates at that site included buttonbush and C. lupulina. Other Canada sites are known from Quebec (Reznicek and Ball 1974).
In New York, the species is known primarily from floodplain forests, silver maple swamps, ponds and marshes, but occurrences are also known from pine plains, orchards, and meadows (NY NHP 1988). Associates at floodplain sites include Acer saccharum, Salix sp., Lythrum salicaria and a species of Impatiens. A site on Lake Champlain is subjected to seasonal flooding by fluctuating lake levels. Forest dominants at the site include silver maple and red maple (Zika pers. comm.).
In Connecticut, the species was known from calcareous swamps, meadows and prairies (CT NDDB 1989, 1983). No known extant populations occur in the state.
Five extant Vermont localities exist for the species, all within the Champlain Valley (Thompson 1989). Habitats include nutrient-rich streamside/lakeside swamps, seasonally inundated pools, lakeshore marshes and slow-moving streams. Associates within the slow-moving stream habitat include Phalaris arundinaceae, Sagittaria sp. and Thelypteris palustris (VT NHP 1989). An associate in the nutrient-rich swamp is Carex typhina, while an associate at the seasonally inundated pool is Lysimachia hybrida.
Three extant populations are known from the DelMarVa Peninsula of Delaware (Naczi pers. comm., Naczi et al. 1986). Populations occur on the edges of shallow, temporary pools in swampy woodlands dominated by Acer rubrum and subject to spring flooding. These swamps are associated with DelMarVa Bays (Naczi et al. 1986). Additional associates at all three sites include Carex lupulina, Clethra alnifolia and Liquidambar styraciflua. Carex gigantea, Carex bullata, and Ludwigia sphaerocarpa were additional associates at some of the sites (Naczi et al 1986). Populations were found in areas varying from partial shade to full sun. The single site possessing full sun was a recently logged-over swampy woods, while the other two sites possessed natural, mature swampy woods (Naczi et al. 1986). The largest population discovered (over 50 plants) occurred at the site that was recently logged, reflecting a possible enhancement of vigor through increased sunlight. At this site, however, the ground layer was not significantly disturbed. Smaller populations of less than 25 plants occurred at the other two sites (Naczi pers. comm.). Acidophiles (eg., Iris prismatica) were observed at the sites, suggesting acidic environments (Naczi pers. comm.).
In New Jersey, C. lupuliformis is most common in the glaciated, northwestern portion of the state, often occurring in intermittent limestone sinkhole ponds. Additional collections have been made from swampy woods, marsh edges and ditches along railroads and roadsides (Snyder pers. comm.). A few verified records also occur on the Atlantic Coastal Plain. Populations vary in size from a few individuals to situations where the species is a dominant. The canopy cover at these sites is open to partially filtered. Characteristic associates include Carex viridula, Mentha arvensis, Boltonia asteroides var. asteroides, Sagittaria cuneata, Cyperus aristatus, Eragrostis hypnoides, Carex retrorsa and Ranunculus flabelaris (Snyder pers. comm.). Nearly all of the populations in New Jersey are associated with limestone bedrock, the sole exception being a Coastal Plain site. Snyder (pers. comm.) has suspected that the Coastal Plain site may be slightly acidic.
Iowa populations are all historical, none observed more recently than 1931 (Gilly 1946, Loeschke pers. comm., Zager pers. comm). Within the state, it has been reported from pond and low, wet lakeshore margins in the southern tier of counties (Gilly 1946).
In Missouri, C. lupuliformis is known from swamps, low wet woods and margins of ponds in river bottoms or other lowland areas (Steyermark 1963) and may now be restricted to the southeast corner of the state (Ladd pers. comm.). Historical records from northeastern Missouri probably came from prairie wetland margins which have largely been destroyed (Ladd pers. comm.).
In Illinois, C. lupuliformis inhabits the margins of swamps and ponds (areas having saturated soils) (Mohlenbrock pers. comm.). Apparently, it is not as common as distribution records tend to indicate. Numerous supposed records are misidentifications of C. gigantea or C. lupulina (Mohlenbrock pers. comm.).
In Mississippi, Bryson (pers. comm.) has observed the species in the Mississippi Delta region in the northwest corner of the state. Plants typically grow in open sunlight along railroad and highway rights-of-way where they are subject to mowing and occasional broadleaf herbicide application. In spite of this, population size was estimated at 300-400 and up to 1000 plants per population. Associates include Carex crus-corvi, C. frankii, C. hyalanolepis (=C. lacustris), C. tribuloides, Juncus sp. and several species in the genus Ranunculus.
Bryson (pers. comm.) also collected the species near Ocala, Florida, from a right-of-way in murky, peaty, heavy soils similar to that used for growing sugar cane. Associates included species typical of a longleaf pine flatwood community and a species of palmetto.
Carex lupuliformis was recently rediscovered in Texas after a 28-year absence (Jones pers. comm.). The extant population occurs in a bottomland hardwood swale in Houston County within the Big Slough Wilderness Area of the Davy Crockett National Forest. Associates include C. joorii, Juncus repens, Erianthus strictus, Planera aquatica, Quercus nigra, Q. lyrata, Sable minor and Panicum rigidulum (Jones et al. 1990, Jones pers. comm.).
Number of Occurrences
Note: For many non-migratory species, occurrences are roughly equivalent to populations.
Estimated Number of Occurrences: 81 to >300
Comments: Likely over 100 occurrences; reportedly relatively common in Kentucky.
Flowering occurs from July through October, with fruit production following shortly thereafter (Jones and Hatch 1990, Steyermark 1963). Population size, based on observations throughout the range of the species (Mohlenbrock pers. comm., Reznicek pers. comm., Zika pers. comm), appears to average roughly 15 individuals. In some areas, however, populations may be substantially larger. Very little is known about the life history of the species.
Carex lupuliformis plays host to a Dipteran parasite, which develops through its larval and pupal stages within the achenes of this and three other closely-related species: C. gigantea, C. louisiana and C. lupulina (Reznicek and Ball 1974). The result of this parasitism is a distortion of the achene length to a longer and more ovoid shape and a distortion in color to a creamy-white. The parasite also causes the perigynia to turn straw-yellow, to spread abnormally, or become retrorse and sterile, filled with distorted achenes. These distortions have led to misidentifications of the species. Botanists have sometimes regarded the infected plants as hybrids between C. lupuliformis and other species. Carex lupuliformis has been known to cross with Carex retrorsa to produce a hybrid, Carex X macounii, in Ohio (Cusick 1981), but it is not known whether this is a supposed hybrid as mentioned by Reznicek and Ball (1974). Some of the specimens from New Jersey have been annotated as intermediate hybrids between C. lupuliformis and C. lupulina (Snyder pers. comm.). These may be an artifact of the Dipteran parasite.
Species within the genus, Carex, have been known to play host for a number of butterfly species. Although C. lupuliformis has never been shown to be a butterfly host, this may be an artifact of its rarity. Several species of butterflies are known to utilize C. lacustris and C. stricta, species sometimes associated with C. lupuliformis, as a host plant (Bryson pers. comm., Scott 1986).
The chromosome number for the species is 2n = 60 (Reznicek and Ball 1974). Jones (pers. comm.) stated that the species may be an aneuploid (not having an exact multiple of the haploid number) derivative of C. lupulina. When C. lupulina left its more mesic habitat to that characteristic of C. lupuliformis, the meiotic processes within the plant presumably were significantly altered, resulting in the origination of C. lupuliformis. Although this is hypothetical, it does give an explanation for the apparent rarity of this species over its wide range.
Life History and Behavior
Molecular Biology and Genetics
Barcode data: Carex lupuliformis
Statistics of barcoding coverage: Carex lupuliformis
Public Records: 3
Specimens with Barcodes: 5
Species With Barcodes: 1
National NatureServe Conservation Status
Rounded National Status Rank: N1 - Critically Imperiled
Rounded National Status Rank: N4 - Apparently Secure
NatureServe Conservation Status
Rounded Global Status Rank: G4 - Apparently Secure
Reasons: Widespread species declining through loss of habitat, rare in many states/provinces in its broad range but relatively common in Kentucky, and not of concern in a few other states.
Global Short Term Trend: Decline of 10-30%
Comments: Declining due to habitat destruction and alterations of hydrology.
Comments: In general, Carex lupuliformis faces the same threats faced by the wetland habitats in which they live. Damming of rivers, drainage of river backwaters via ditching or channelization, floodplain cultivation and the interference of the spring flood cycle are the major threats to the species throughout its range (Reznicek pers. comm.). In Texas, bottomland forests are being logged and the rivers dammed, vastly diminishing the potential suitable habitat still in existence, and posing threats to undiscovered populations (Jones pers. comm.). This habitat conversion is also a threat to possible populations within the southeast corner of Wisconsin (Meyer pers. comm.). Snyder (pers. comm.) stated that the draining, ditching and filling of wetlands are the major threats in New Jersey, although habitat succession and ATV's are additional concerns.
Logging of floodplain forests may artificially create the open, sunlit habitat preferred by C. lupuliformis, initially producing an explosion of new genets within a population. In the years following this activity, however, the forest canopy will close due to excessive shrub and tree growth, and destroy the habitat in which the pre-logging population flourished.
Exotic plant species may pose threats at some sites (Zika pers. comm.). At drier sites, Lonicera japonica may be a problem, while at wetland sites the emergent Butomus umbellatus may pose problems. Moderately moist sites may be invaded by purple loosestrife (Lythrum salicaria).
Wetland sites, particularly those occurring in lakeshore habitat may be subjected to aquatic weed control measures, including herbicide applications (Zika pers. comm.).
In Mississippi, Bryson (pers. comm.) stated that populations often occur in railroad and highway rights-of-way and are, consequently, subjected to broadleaf herbicide application and mowing. Since carices are monocots, broadleaf herbicides do not pose a threat to the populations. Mowing apparently does not cause significant damage. These populations may become threatened by highway construction or the use of broad-spectrum herbicides, however.
Restoration Potential: The recovery potential of this species is not entirely known, but it may be hypothesized that the potential is not very great. Apparently the species has a wide extant distribution, but is very rare throughout most of its range. Historical records of occurrences, through herbaria, indicate that the species was probably never common, even when habitat was plentiful and threats minimal. Consequently, it is doubtful, even with adequate protection, that species numbers will rise to such a level as to eliminate the need for tracking and protection.
Protection of some of the sites is probably necessary as suitable habitat diminishes. Artificial maintenance of open, floodplain habitat through mowing, brush cutting or herbicide application, may significantly enhance existing populations. The enhancement of population size under the above conditions has been noted in the field. Although these sites are probably not ideal in terms of natural area quality, they do provide valuable information for the maintenance of the species, if range-wide population numbers significantly decline.
It is not believed that artificial dispersal and planting of this species is necessary for its survival at the present time. Within portions of its range, the species may be relatively common. A range-wide survey of the species needs to be undertaken in order to ascertain whether the species is in need of this type of measure.
Preserve Selection and Design Considerations: Being aquatic or semi-aquatic in nature, Carex lupuliformis is highly susceptible to alterations of the wetland habitats in which it is found. The species may have a need for seasonal flooding, whether it occurs in aquatic habitats or wet floodplain forests. In any case, maintenance of unaltered aquatic systems, complete with seasonal flooding cycles, is apparently essential for the well-being of the species. These same flooding cycles produce the desired openings within a given floodplain or wetland habitat. Therefore, entire watersheds must remain largely intact with respect to natural water flow, regardless of whether the habitat is a marsh, lake border, river or pond. Small watersheds are more susceptible to alterations than larger systems.
Erosion and pollution control from agricultural fields and other sources may also be necessary in order to fully protect the species. It should be pointed out that it is not certain to what extent siltation diminishes the quality of a given population. Generally, highly erodible lands within a watershed should be taken out of production, while farming methods compatible to the enhancement of river systems should be encouraged, including contour farming, grass waterways and riparian buffer strips.
Two populations within the state of New Jersey possess some degree of protection, one being within a State Park, the other within a TNC registry site. Other protected sites are currently unknown.
Management Requirements: Maintenance of low competition, semi-open vernal pond shorelines (Meyer pers. comm.), floodplain forests and wetland marshes may be necessary for this species. Jones (pers. comm.) stated that maintenance of flooding cycles and suitable wetland habitats (riverine backwaters, marshes, swamps, etc.) are also essential for the survival of the species. All extant populations of this species occur in habitats where annual flooding cycles and natural groundwater levels have not been seriously altered. The natural flooding regime may have maintained openings within the floodplain forest ecosystem. In addition, elimination of periodic fires, once initiated by Native American Indians, may have succeeded in decreasing the quantity of wetland and floodplain openings.
Preferred management is to let the natural flooding regime work to create openings and habitat within a given system. This methodology may not adequately work in areas where the natural flooding regime has been manipulated. In such instances, artificial maintenance of openings may need to be undertaken through opening of the forest canopy and cutting of shrubs.
Many populations occurring on railroad, highway or power line rights-of-way, although generally not occurring in prime habitat, are the largest known in terms of individual numbers. Maintenance of these populations at such artificially elevated levels must rely on the eradication of woody competition through mowing, manual cutting or broadleaf herbicide application. In most instances, the jurisdiction in charge of the right-of-way maintains it in such a way as to eliminate woody plant encroachment. Maintenance frequently occurs through any of the above methodologies.
Competition from exotic species, including Butomus umbellatus, Lythrum salicaria and Lonicera sp., may reduce the overall quality of Carex habitat (Zika. pers. comm.). When present at a site, these exotic species should be manually removed, if possible. If this is not possible, the manager may need to consider whether broadleaf herbicide application may be warranted for Lythrum salicaria and species of Lonicera. Butomus umbellatus is a monocot so herbicide application for this species would also eliminate C. lupuliformis.
Monitoring Programs: Since Carex lupuliformis is ranked as a G3G4Q, some states are not currently tracking this species. This is the case in Indiana (Homoya pers. comm.) and in Illinois, where historical records are believed to exist for the species in 42 of the 102 counties in the state (Karnes pers. comm.).
The G-rank (global rank) is used by The Nature Conservancy to indicate an element's global status. In this case, G3G4 signifies that there exists some uncertainty over whether the species is globally threatened (between 21 and 100 extant occurrences = G3) or is apparently secure (over 100 extant occurrences although it may be rare in parts of its range = G4). Its Q-rank suggests that its taxonomic status is uncertain, although most, if not all, people currently working on C. lupuliformis believe that it is a distinct species (Bryson pers. comm., Jones pers. comm., Naczi pers. comm., Reznicek pers. comm.).
The Wisconsin Heritage Program is currently monitoring the population at one site on a 2-5 year cycle. No formal procedures are being used, but individual plant counts are conducted. Contact: Thomas Meyer, Wisconsin Natural Heritage Program, Endangered Resources/4, Department of Natural Resources, 101 S. Webster St., Box 7921, Madison, WI 53707. Telephone No. (608) 266-0394
Biological Research Needs: Meyer (pers. comm.) stated that intensive inventories through appropriate habitat in central and southeastern Wisconsin are necessary. These surveys need to be conducted throughout the range of this species in order to fully elucidate the current status of the species. Many of the historical records are likely misidentifications of Carex lupulina and other closely related sedges.
In order to determine the reason for the species' rarity throughout its range, its life history will have to be studied. At present, little or no information regarding the life history of the species is known. Information relating to dispersal and habitat requirements are particularly needed.
Stanley Jones of the Department of Range Science at Texas A&M has been working on Carex section Lupulinae in Texas. A paper on the carices of this section will appear within Sida this coming year (1991). Contact: Stanley Jones, Department of Range Science, Texas A&M University, College Station, TX 77843. Telephone No. (409) 845-7917.
Relevance to Humans and Ecosystems
Stewardship Overview: Populations should be monitored in order to track changes in population size and new recruitment into the population. Research should be centered around the completion of a range-wide status survey of the species, coupled with aspects relating to the species' life history. Management via natural succession and flooding regimes is the most preferred of a number of management tools. Mechanical removal of encroaching shrubs and small trees, mowing or broadleaf pesticide application are alternative management techniques that may be used in areas where floodplain forests have been logged or otherwise cleared, or the natural flooding regime has been disturbed. Competing exotic plant species should be manually removed.
Names and Taxonomy
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