Corema conradii - (Torr.) Torr. ex Loud.
Broom Crowberry
Other Common Names: broom crowberry
Taxonomic Status: Accepted
Related ITIS Name(s): Corema conradii (Torr.) Torr. ex Loud. (TSN 23750)
Unique Identifier: ELEMENT_GLOBAL.2.156445
Element Code: PDEMP02010
Informal Taxonomy: Plants, Vascular - Flowering Plants - Other flowering plants
Kingdom Phylum Class Order Family Genus
Plantae Anthophyta Dicotyledoneae Ericales Empetraceae Corema
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Concept Reference
Concept Reference: Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Concept Reference Code: B94KAR01HQUS
Name Used in Concept Reference: Corema conradii
Taxonomic Comments: GRANK assigned by botanists during Eastern Heritage Conference (92-11-11).
Conservation Status

NatureServe Status

Global Status: G4
Global Status Last Reviewed: 13Jul1993
Global Status Last Changed: 16Nov1992
Rounded Global Status: G4 - Apparently Secure
Nation: United States
National Status: NNR
Nation: Canada
National Status: N4 (06Sep2017)

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States Maine (S3S4), Massachusetts (S3), New Jersey (S2), New York (S1)
Canada New Brunswick (S1), Nova Scotia (S4), Prince Edward Island (S2), Quebec (S3)

Other Statuses

NatureServe Global Conservation Status Factors

Range Extent Comments: Mostly along the coast from Newfoundland south to New Jersey, but disjunct inland at Ulster County, NY. Canada: E Que. (Magdalen Is.), Nfld., P.E.I (Bothwell, Murray River, and Bristol)., N.S.(scattered in southern Yarmouth and Shelburne Co.; common onthe sand plains of the Annapolis Valley, and in Colchester and Cumberland Co. on the sandiest soils; on the rocky barrens of Halifax Co. near the coast and rare to Antigonish and Guyborough).

Population Size Comments: Has the following state ranks: MA-S3; ME-S3S4; NJ-S1; NY-S1; QC-S1.

Overall Threat Impact Comments: The primary threats to C. conradii can be summarized as: lack of frequent fire causing habitat succession, deer browsing, shoreline or cliff erosion, human trampling, and development in the form of quarrying, sand mining, housing or road construction. Many populations are located on old or current firing ranges at military bases. Given the current trend towards military base closures the potential changes in land use at these locations poses an important threat to these populations.

Forest succession and fire suppression are clear threats (Sorrie, 1987). C. conradii is capable of persisting in open pine woods without a shrub understory, but is shaded out by shrubs such as huckleberry or Empetrum.

The negative impacts of deer browsing and other threats were analyzed in a report on the New York population, consisting of approximately 50 plants (Huth and Smiley, 1982). Deer browsing is suspected to be a major factor causing a decline of C. conradii at this location (Huth and Smiley, 1982). The effect of an increasing deer population during the 1950's is evident. Between 1957 and the present, dead C. conradii plants were observed and live ones noted to be damaged by browsing, with the first record of browsing being in the Palmaghatt area in 1954 (Huth and Smiley, 1982). Previous accounts make no mention of deer browsing (Smiley, 1939; 1940). In 1981 only 30 to 40% of the plants present at Gertrude's Nose were living, with numerous dead shrubs 10 to 16 inches in diameter (Huth and Smiley, 1982). Ledges of the cliffs facing Palmaghatt which are inaccessible to deer have been observed to support vigorous healthy stands (Huth and Smiley, 1982).

Road and housing construction, as well as quarrying and sand mining are obvious threats which result in loss of habitat. One site could potentially be threatened by airport expansion on Nantucket, if such activities were ever planned (Zaremba, 1984). Vehicles driving over C. conradii individuals result in trails of dead plants through the remaining live plants (Zaremba, 1984). However, C. conradii does often colonize road shoulders and disturbed areas, making roads and abandoned quarries or mines beneficial for the species by creating potential open habitat in otherwise unavailable habitat.

Shoreline erosion is a problem for populations on bluffs such as those in Nantucket and Provincetown. A major drought in the 1960's on the New York population does not appear to have lasting effects (Huth and Smiley, 1982), and C. conradii is probably well adapted to low water supply. C. conradii is also tolerant of moderate salt spray, however, several sites on Nantucket which receive salt spray contain exceptionally low growing individuals (Zaremba, 1984).

Short-term Trend Comments: Declining over most of its range, yest still dominant over many acres on Nantucket and outer Cape Cod, where it colonizes sandy barrens, roadsides, scrapes, and burns (Sorrie, 1987, Rhodora 89:164-165).

Other NatureServe Conservation Status Information

Global Range: Mostly along the coast from Newfoundland south to New Jersey, but disjunct inland at Ulster County, NY. Canada: E Que. (Magdalen Is.), Nfld., P.E.I (Bothwell, Murray River, and Bristol)., N.S.(scattered in southern Yarmouth and Shelburne Co.; common onthe sand plains of the Annapolis Valley, and in Colchester and Cumberland Co. on the sandiest soils; on the rocky barrens of Halifax Co. near the coast and rare to Antigonish and Guyborough).

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map

U.S. & Canada State/Province Distribution
United States MA, ME, NJ, NY
Canada NB, NS, PE, QC

Range Map
No map available.

U.S. Distribution by County Help
State County Name (FIPS Code)
MA Barnstable (25001), Dukes (25007), Essex (25009)*, Nantucket (25019), Plymouth (25023)
NJ Burlington (34005), Ocean (34029)
NY Ulster (36111)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
01 Charles (01090001)+*, Cape Cod (01090002)+
02 Rondout (02020007)+, Lower Delaware (02040202)+, Mullica-Toms (02040301)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
Basic Description: Plant, bushy-branched shrub, Empetraceae.
General Description: Corema is a low, dense, evergreen shrub usually less than half a meter tall that spreads out in the shallow soil between open rock formations. It is highly branched with tiny, narrow evergreen leaves, green above and white below, covering the branches. The separate male and female flower heads form in a rosette of leaves at the tips of the branches. There are no petals but the other flower parts give a purplish cast to the plant in early spring.
Technical Description: Low growing, evergreen ericaceous shrub. Usually not more than 30 cm tall in New Jersey or Massachusetts (Dunwiddie, 1990) and up to 60 cm tall in Nova Scotia and Newfoundland (Woodford, 1979).

Stem: The basal portion of the shrub is a tangle of brown stems and dead branches, with the surface covered with small slender, needle-like leaves (Harshberger, 1916).

Leaves: Numerous pulvinate, subverticillate leaves (Wood and Channell, 1957). These leaves roll inward to create a cavity protected by unicellular and multicellular hairs on the edge of the leaf. Stomata are located on the inner surface, and guard cells project out from both sides of the leaf surface. The outer surface is covered by a thick cuticle with multicellular capitate hairs (Harshberger, 1916).

Inflorescence: Terminal few flowered clusters in the axils of a scaly bract, with five or six bractlets (Harshberger, 1916).

Flowers: Dioecious or polygamous, inconspicuous sessile apetalous flowers. Calyx of three or four sepals, no corolla, three or four exserted stamens with thin elongated filament, three cleft slender style, and narrow, often toothed stigma. Tufted purple filaments and brownish purple anthers give a dull red appearance to the plants when flowering (Gleason, 1952; Harshberger, 1916).

Fruits: Three, occasionally four carpellate, and drupaceous. Erect seeds fill the cell of each pyrena, with a taper embryo in the axis of the fleshy albumin, two thirds its length, an inferior radicle and short cotyledons (Gray, 1848). The mature drupes are less than 1.5 mm in diameter with a thin coating of juiceless flesh, and do not open at maturity (Gray, 1848).

Diagnostic Characteristics: Similar in appearance to Hudsonia ericoides, with which it is sometimes confused. Hudsonia is dark green with yellow flowers, wheras Corema is brown in winter and yellow-green in the summer, with purple or reddish flowers. It is also similar to true heather, Calluna or Erica, which have pink to lavender flowers. The name C. conradii is derived from the Greek word choreein, broom, in reference to it's bushy habit (Gleason, 1952).

Corema is one of three genera in the Empetraceae, along with Ceratiola Michx., a monotypic genus of the southeastern coastal plain with reported allelopathic properties (Williamson et al., 1992), and Empetrum, a boreal species in southern South America. There are two species, C. conradii (Torrey) Torrey ex Loud. in North America, and C. album (L.) D. Don in Portugal and the Azores (McEwen, 1894; Wood and Channell, 1959).

The Empetraceae are considered closely related to the Ericaceae, based upon pollen morphology (Kim et al., 1988) and other characteristics. Both orders share the characteristic of having pollen in tetrahedral tetrads, whereas other potentially closely related groups have monads instead (Kim et al., 1988). A study of leaf flavonoids in the Empetraceae found a geographical component to the patterns of variation, with C. conradii having more similarities to the North American genus Ceratiola than to Corema album in Europe (Moore et al., 1970).

Ecology Comments: C. conradii is favored by disturbances which open the forest canopy, and is often found on the edges of roads or at recent burns (Sorrie, 1987). C. conradii often occurs on recently disturbed gravelly, sandy, or rocky soils and well drained soils that have been subjected to many years of grazing or fire. These areas include sandy pine-barrens, sand-hills, and siliceous rock formations. C. conradii sites are found on both the morain and outwash plain.

High fire frequency is considered important for the creation of habitat suitable for C. conradii. This high fire frequency is also the most important factor in the development of the Pine Plains area where most C. conradii in New Jersey is found. Pines in this area have developed adaptations such as serotinous cones, slower growth and earlier cone production than pines outside of the plains (Good, Good, and Andresen, 1979). Many C. conradii populations in other states also occur with stunted Pinus rigida. Adult C. conradii is not considered tolerant of fire as with P. rigida. Instead, fire appears to play a role in seedling germination and establishment and the removal of competitors.

C. conradii is one of the first species to bloom, usually in mid to late March (Dunwiddie, 1990). The small flowers are wind pollinated, and ants have been suggested to be important for fruit dispersal in early July (Dunwiddie, 1990). Aphaenogaster rudis ants have been observed collecting fruits where the basal portion of the fruit had developed into a white fleshy structure functioning as an eliasome (Dunwidddie, 1990).

C. conradii grows either as a dense cushion up to 3 dm tall, or as separate widely scattered stems. On Nantucket, where it grows abundantly, it always grows as a dark green cushion form (Harshberger, 1911). This has been suggested to be the result of reproduction from scattered seeds (Harshberger, 1911).

Several C. conradii stands exist in Nantucket on areas which have been graded to expose outwash gravel. Plants in these areas are very low growing and have bare gravelly areas between individuals (Zaremba, 1984). The barren soils in Nantucket resulting from long years of sheep grazing, frequent fires and the stressful climate may have resulted in the extensive stands of C. conradii found in the Central Moors and Madequecham Valley area (Zaremba, 1984).

C. conradii often grows in extensive colonies, covering up to 40 acres at one site on Nantucket with 80-100% cover (Zaremba, 1984). Individual tussocks grow up to one meter in diameter, but can be larger. The average life span has been estimated to normally be approximately 50 years based upon the amount of woody tissue and rate of annual production (Zaremba, 1984). Young plants can produce 8 cm of stem growth in a year, and older ones approx. 0.5 cm of growth (Zaremba, 1984). When C. conradii persists after being overtopped by shrubs it sometimes grows to a height of 40 cm instead of the usual maximum of 25 cm. The leaves of C. conradii are dark brown in the winter, with new yellow green leaves produced in late spring. These leaves are full grown by mid-summer when the previous year's leaves drop (Zaremba, 1984). As C. conradii ages, new growth is concentrated to the outside, resulting in a cluster of grey stems tipped with new growth. The amount of stem growth can be used to roughly age plants. Young plants can produce up to 8 cm of stem per year, and older ones only .5 cm of new stem per year (Zaremba, 1984). After about 35 years plants begin to senesce, with the center dying and leaving only the rooted outer portions alive. Sometimes these plants will appear as rings of living tissue 3-5 m wide, with other species colonizing the center. More commonly a large stand of C. conradii will be composed of small mounds of leafless woody material marking the original centers of older plants (Zaremba, 1984).

Abundance of C. conradii constantly shifts as plants die out or are eliminated by fire in some spots and new plants are established from seed at other locations. Research on prescribed burning indicated that fire kills adult Corema plants, but results in abundant seedling regeneration (Dunwiddie, 1990). Stands of C. conradii are often even aged, with C. conradii seedlings all establishing at once after a major disturbance such as fire (Zaremba, 1984). At one site on Nantucket an even aged stand persists in an area which burned extensively in 1947. In approximately 1982 the plants all had a high percent of woody material, low annual production, and occasional dead plant centers. These plants were described as "late middle aged" (Zaremba, 1984).

Seedlings of C. conradii establish themselves in areas of open sunlight where they grow and persist until overstory shade limits or kills them. Corema is sometimes a pioneer species at recently disturbed sites with exposed gravel. C. conradii often grows in gravel pits and along road embankments, with older plants in undisturbed upland sites expanding into newly exposed gravel. While one might expect to find seedlings in these exposed gravel areas, they are usually not present (Zaremba, 1984).

Germination success of C. conradii collected from Massachusetts and Maine was investigated by Nicholson and Alexander (undated). Germination was very low in all treatments reaching a maximum of 7.3% with no pretreatment procedures. Other treatments favorable for germination involved cold stratification and scarification with mortar and pestle or sulfuric acid. These results differ from expectations based upon field observations, as freshly abscised fruits have not been observed germinating in the field, and a replicate lot of fresh seeds produced no germination (Nicholson and Alexander, undated). Reports of seedlings observed in the field after fire (Dunwiddie, 1990; Redfield, 1889) suggests that heat should stimulate germination, however heat treatments produced no germination (Nicholson and Alexander, undated). Germination of seeds of other heathland species have been found to be stimulated by high temperatures (Mallik and Gimingham, 1985). Seedling germination of C. conradii in the field is usually almost nonexistent except after fire. Redfield (1889) describes after a burn "myriads of young seedling plants of the C. conradii springing out of the if the seeds carried by the winds had availed themselves of every spot of bare sand, there to lodge and germinate." Dunwiddie (1990) observed seedlings germinating in the fall two successive years after a prescribed burn in April, but almost no seedlings before the burn.

Interest in C. conradii has resulted in transect surveys of communities with C. conradii in Quebec and in Nantucket. Populations in Quebec in the Magdalen Islands are sporadic on fixed sand dunes in openings in conifer stands and Empetrum dominated trailing shrub communities (Gagnon, pers. comm.). The fixed sand dune habitat is limited, covering 5% of the island (Grandtner, 1967) The species is known from at least four sites, one of which is protected within a National Wildlife Refuge Area at Pointe de l'est. An inventory of a 1 km transect in the Sillons area found C. conradii present along 10% of the area, along with a >50% presence of Ammophila breviligulata, Arctostaphylos uva-ursi, Empetrum atropurpureum, E. hermaphroditum, Festuca rubra, Juncus balticus, Juniperus communis, Myrica pensylvanica, Solidago bicolor, Vaccinium angustifolium, and Caldina spp. (Gagnon, pers. comm.).

The three major C. conradii stands on Nantucket have large central areas with a high cover of C. conradii and few oaks or pines. On the edges, these areas grade into oak and pine heathlands with sparse C. conradii. Checklist plots were established at 12 of 15 Nantucket populations in 1983, and 21 plots containing C. conradii were surveyed for species abundance. The cover in the largest stands approached 90-100% C. conradii. The mean species diversity was 27.5 species per plot. This was greater than the average number of species per plot for all sampled Nantucket heathlands (22.8). Plots in communities dominated by C. conradii have a mean species number of 23.4, while plots where C. conradii was present at low density have a high species diversity (32.7). Areas with very high C. conradii cover have as few as 13 species per plot.

C. conradii occurred in areas described as bearberry, huckleberry, mixed ericaceous shrubs, and oak heathlands. All of the ericaceous flora of Nantucket occurs in association with C. conradii. The most common ericaceous species in association with C. conradii were Arctostaphylos Uva-ursi, Gaylussacia baccata, Vaccinium angustifolium, Hudsonia ericoides, Comptonia peregrina and Myrica pensylvanica. Both Gaultheria procumbens and Epigaea repens occasionally occur in high abundance in association with C. conradii. A wide range of composite species occur with C. conradii, with the most common being Aster linariifolius, Solidago puberula, and Aster paternus (Zaremba, 1983). All of the principal Nantucket heathland composite species occur in association with C. conradii, and secondary heathland composites occurred at C. conradii sites associated with disturbance, sand pits, or recently graded sites (Zaremba, 1983).

Grasses and sedges also occur with C. conradii, and are more abundant in early successional or stressed areas. The most abundant are Schizachryium scoparium, Danthonia spicata and Carex pennsylvanica. Rare heathland species also occur, with Hilanthemum dumosum and Amelanchier nantucket being the most frequently found rare species. Rare species are principally associated with older stands in areas without recent disturbance, however, the abundance of rare species decreases as the percent cover of C. conradii increases (Zaremba, 1984). Other common species which commonly occur with C. conradii include Cladonia spp., Quercus ilicifolia, Q. prinoides, Pinus rigida and Baptisia tinctoria.

C. conradii populations on the Provincetown peninsula were surveyed by LeBlond (1983). The populations were found to occur in relict dune ridges, pine barrens, embankments along a road and railroad bed, and in a rejuvenated dune system near the Province Lands Visitor Center at Cape Cod National Seashore. With the exception of the more recent dune system near the visitor center, C. conradii is restricted to older podzel soils and sand of relict dunes. It is unknown whether many large areas of other rejuvenated dunes would provide suitable habitat for C. conradii (LeBlond, 1983). Some sites exist on old military bases, as in Nantucket, where firing ranges produced high disturbance and frequent fire.

Intermittent monitoring of the New York population of C. conradii has resulted in the accumulation of records over a 100 year span documenting a decline in the population size (Huth and Smiley, 1982). Original reports of the population by A. H. Smith (1882), C. E. Smith (1880, 1882), and Redfield (1884) describe the population as locally abundant on ledges and sunny open places. Torrey (1932) described the Gertrude's Nose population as isolated from fires by vertical cliffs to the west and south, a wet swale to the north, and thin vegetation to the east and northeast.

Habitat Comments: Occurs in disjunct populations usually along the coast from Nova Scotia and Newfoundland to the New Jersey Pine Barrens. Extant populations of C. conradii occur in Quebec, Newfoundland, Massachusetts, Maine, New York and New Jersey. The coastal heathlands where Corema occurs in the northeast are considered threatened throughout their range (Dunwiddie, 1990).

Within Canada, populations occur in east Quebec on the Magdalen Islands; in Newfoundland, on Prince Edward Island at Bothwell, Murray River, and Bristol (Fernald, 1911); in Nova Scotia scattered in southern Yarmouth and Shelburne Counties, the sand plains of the Annapolis Valley, in Colchester and Cumberland Counties on the sandiest soils, and on the rocky barrens of Halifax County near the coast, rarely to Antigonish and Guyborough (Fernald, 1921).

In Maine, numerous often large populations occur on sandy soils or rocky granite and igneous bluffs on coastal mountains between patches of Empetrum nigrum, Pinus rigida, P. strobus, Picea strobus, or stunted Quercus forests. Locations include Bath, Isle au Haut, Kimball's Island, and Mt. Desert (Harshberger, 1970; Norton, 1913).

It is found within Massachusetts on coastal islands and the coastal plain in sandy barrens, in association with Pinus rigida, Betula populifolia, Vaccinium vacillans and Comptonia peregrina. C. conradii is thought to be declining in Massachusetts, but is still dominant over many acres on Nantucket and outer Cape Cod (Sorrie, 1987). Nantucket is the location of the largest, densest stands of C. conradii in Massachusetts. It also occurs at Plymouth, Truro, and the Elizabeth Islands (Fogg, 1930; Harshberger, 1970).

A non-coastal population occurs in central New York in Ulster County, on the Shawangunk Mountains. This inland region has many other disjunct coastal species besides C. conradii.

It occurs in New Jersey growing on coarse sand within the southern New Jersey Pine Barrens and Pine Plains (Stone, 1911). C. conradii was first described from a New Jersey population, when it was discovered by Dr. Soloman Conrad in 1831 near Pemberton Mills, NJ (Redfield, 1884). The greatest abundance of C. conradii in New Jersey is found in the Pine Plains, a region of dwarf pitch pine (Pinus rigida), commonly less than 10 ft. tall, in dry open sand plains which experience frequent disturbance and fire. No plants are endemic to the plains, but C. conradii, pixie moss (Pyxidanthera barbulata), and bearberry (Arctostaphylos uva-ursi) are all more abundant there than elsewhere (Good, Good, and Andresen, 1979). One occurrence outside the plains to the east was described by Stone (1911) as an elevated sandy bluff overlooking bogs, with wind swept, low vegetation. C. conradii was present along with Arctostaphylos, Hudsonia ericoides, and Dendrium.

The habitat of the Pine Plains was described by Redfield (1889): "The region is a remarkable one, which cannot fail to impress every visitor with a sense of loneliness and sterility...these so-called "plains" are long undulating swells of sand, sometimes rising to a height commanding extensive views in every direction over a desert of sand so sterile that even the trees of Pinus rigida, which sparsely clothe it, can attain only to the height of three or four feet. No sign of human life is visible and one could readily imagine himself in the midst of a vast wilderness." Other descriptions of C. conradii locations and antecdotal accounts in New Jersey were summarized by Brown (1913) and Stone (1912).

Many species occurring in the flora of Newfoundland have a southern coastal association, including C. conradii (Harshberger, 1916). The disjunct populations of C. conradii and other species which exist in Newfoundland and on islands along the New England coast are thought to be a result of unequal depression during post-glacial times of the elevated coastline. These depressions caused the formation of islands where the disjunct populations were preserved (Harshberger, 1916). After glaciation, cold conditions and low nutrient, gravelly soils were present on the outwash plain. C. conradii was able to survive the changes in climate and increasing competition with the invading temperate zone species.

Economic Attributes Not yet assessed
Management Summary
Stewardship Overview: C. conradii is an unique species which has attracted much attention by botanists over the years due to it's disjunct distribution, scenic and unusual habitat requirements, and dioecious nature. It has not been the subject of much formal research or protection efforts, although it has high name recognition among conservationists. This species is not presently considered federally endangered, and conservation efforts before populations becomes depleted would be invaluable in preserving the genetic diversity of this species. Many populations are protected within state parks, however, prevention of the development of private property or U. S. military bases containing populations of C. conradii should be a high priority. Populations may also require active management, probably in the form of prescribed burning, to maintain the disturbance regime needed by populations.
Restoration Potential: Potential for recovery of declining populations in most cases is good if the reason for decline is a lack of disturbance in the form of fire. Prescribed burning is likely to result in Corema regeneration, as well as the elimiation of competing shrubs. Populations suffering from deer browsing or shoreline erosion have less recovery potential due to the difficulties of eliminating the reasons for their decline.
Monitoring Requirements: While some effort has been made to count numbers of plants at smaller populations and survey associated species, very little detailed demographic information is available on C. conradii. Mapping of individual plants is difficult due to their size and spreading nature. Monitoring of the size of the area colonized by C. conradii populations over time and the numbers and sizes of individuals is needed to determine the vigor of populations. The impact of invading pines, oaks, and shrubs as shading increases also needs to be investigated. In areas where the fire history is known, it is likely that the time since fire and age of individuals would be highly correlated.

Procedures for the monitoring of a population would depend upon the size of the population and goals of the monitoring. Generally, the number and age of adults, the amount of seedling regeneration, the frequency of past and present disturbance, the spatial scale of disturbance in relation to the size of the population, and diversity and density of associated species should be assessed. For large populations the most important factor to monitor would be the disturbance history and any negative effects of the disturbance. The effects of disturbance can be difficult to assess for partially disturbance dependent species such as C. conradii.

Management Programs: Throughout it's range C. conradii is partially protected within state parks. In New Jersey populations are partially protected within a State Natural Area which is intended to be managed for preservation of the globally rare Pine Plains community as well as habitat for endangered or threatened species. This natural area is within the much larger Pinelands National Reserve (Russell, 1994).

Some of the relic dune ridge populations in Provincetown have been donated to the Provincetown Conservation Trust (LeBlond, 1983).

Monitoring Programs: Populations of C. conradii are often sporadically monitored, with several one-time transect surveys existing as well as detailed historic descriptions of many populations. Monitoring often occurs within state park boundaries in association with general vegetation monitoring. Formal monitoring programs are generally not in existence although they would be beneficial.
Management Research Needs: Management of populations should take into account the types of threats to the population. Prescribed burning would be advantageous to most populations. Management of deer populations may be necessary in areas where browsing is a problem, such as in the Shawangunks. Management should focus on creating a disturbance regime which will maintain or expand current populations of C. conradii.
Population/Occurrence Delineation Not yet assessed
Population/Occurrence Viability
U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
NatureServe Conservation Status Factors Edition Date: 01Jul1994
NatureServe Conservation Status Factors Author: C. Annable; rev. ELIZABETH M. OBEE, STATE OF NEW JERSEY DEPARTMENT OF
Management Information Edition Date: 01Jul1994
Element Ecology & Life History Edition Date: 01Jul1994

Botanical data developed by NatureServe and its network of natural heritage programs (see Local Programs), The North Carolina Botanical Garden, and other contributors and cooperators (see Sources).

  • Bouchard, A., D. Barabé, M. Dumais et S. Hay 1983. Les plantes vasculaires rares du Québec. Syllogeus no 48. Musées nationaux du Canada. Ottawa. 75 p.

  • Brown, S. 1913. Corema conradii Torrey. Bartonia 6: 1-7.

  • Couillard, L., D. Pelletier et J. Gagnon 1996. La situation du corème de Conrad (Corema conradii) au Québec. Gouvernement du Québec, ministère de l'Environnement et de la Faune, Direction de la conservation et du patrimoine écologique, Québec. 43 p.

  • Dunwiddie, P.W. 1990. Rare plants in coastal heathlands: Observations on Corema conradii (Empetraceae) and Helianthemum dumosum (Cistaceae). Rhodora 92: 22-26.

  • Fernald, M.L. 1911. A botanical expedition to Newfoundland and southern Labrador. Rhodora 13: 133-162.

  • Fernald, M.L. 1911. The northern variety of Gaylussacia dumosa. Rhodora 13 95-99.

  • Fernald, M.L. 1918. The geographic affinities of the vascular floras of New England, the Maritime provinces and Newfoundland. American Journal of Botany 5 219-236.

  • Fernald, M.L. 1921. Expedition to Nova Scotia. Rhodora 13: 136-273.

  • Fernald, M.L. 1929. Some relationships of the floras of the northern hemisphere. Proc. Int. Congr. Plant Sci. 2 1487-1507.

  • Fernald, M.L. 1950. Gray's manual of botany. 8th edition. D. Van Nostrand, New York. 1632 pp.

  • Fimbel, R.A. and J.E. Kuser. 1993. Restoring the pygmy pine forests of New Jersey's Pine Barrens. Rest. Ecol. 4: 117-129.

  • Fleurbec / G. Lamoureux, S. Lamoureux, A. Tousignant, L. Cournoyer et R.F. Gauthier / 1994. Plantes susceptibles d'être désignées menacées ou vulnérables. Noms français de 229 espèces. Rapport non publié, préparé pour le gouvernement du Québec, ministère

  • Fogg, J.M. 1930. The Flora of the Elizabeth Islands, Massachusetts. Rhodora 32: 167-179.

  • Gleason, H.A. 1952. The new Britton and Brown illustrated flora of the northeastern United States and adjacent Canada. 3 volumes. Hafner Press, New York. 1732 pp.

  • Gleason, Henry A. and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York. 910 pp.

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