Empetrum nigrum ssp. hermaphroditum Stephen M. Young

Empetrum nigrum ssp. hermaphroditum
Stephen M. Young

Class
Dicotyledoneae (Dicots)
Family
Empetraceae (Crowberry Family)
State Protection
Rare
A plant listed as Rare by New York State. Removal or damage without the consent of the landowner is prohibited.
Federal Protection
Not Listed
State Conservation Status Rank
S3
Vulnerable in New York - Vulnerable to disappearing from New York due to rarity or other factors (but not currently imperiled); typically 21 to 80 populations or locations in New York, few individuals, restricted range, few remaining acres (or miles of stream), and/or recent and widespread declines.
Global Conservation Status Rank
G5T5
Secure globally - Both the species as a whole and the subspecies/variety are common in the world; widespread and abundant (but may be rare in some parts of its range).

Summary

Did you know?

The genus name Empetrum comes from the Greek en, which means upon, and petros, which means rock (Fernald 1970). This name alludes to the way this species grows on rocks. The common name black crowberry refers to the black color of the fruits and makes reference to the fact that, at least in the arctic where this plant also grows, birds relish the fruits (Waller and DiGregorio 1997). This plant's Inuit name, paurngait, means "which looks like soot", and refers to the black berries (S. G. Aiken et al 1989).

State Ranking Justification

There are 19 known populations. Nine of these populations are ranked excellent or good. Some of these are quite large with one containing an estimated 250,000 individuals. The overall range of the extant populations is relatively small. All the populations are restricted to the high peaks region of the Adirondacks. There are an additional two populations, also from the high peaks region, that have not been seen in over 85 years but additional survey work is needed before these populations can be determined extirpated. There is also one disjunct population known from the South Fork of Long Island which has not been seen since 1924. This population is believed to be extirpated.

Short-term Trends

There are no clear data on short-term trends, although trampling by hiker traffic has most likely, at least slightly, reduced the size of many populations in recent years.

Long-term Trends

The one disjunct population from eastern Long Island has not been seen since 1924. There is strong evidence that it was destroyed due to erosion caused by the ocean. There are two additional populations that have not been seen in over 85 years but additional survey work is needed to determine if these populations are still extant. Therefore, long term trends indicate at least a slight decline in the past 150 years.

Conservation and Management

Threats

At many of the populations trampling by hiker traffic threatens at least parts of the populations. Left unchecked, global climate change is also a threat.

Conservation Strategies and Management Practices

The Summit Steward program which works to inform hikers of the fragile nature of alpine plants is a critical program which is helping to reduce trampling of alpine vegetation. This program and other efforts designed to reduce trampling of alpine meadows are needed.

Research Needs

Additional survey work is needed at the two populations which are only known from historical records to determine if these populations are still extant. Further survey work in the high peaks region may turn up additional populations. Clear and consistent estimates of population size at extant populations is needed to help determine the trend of this species.

Habitat

Habitat

In New York, this species occurs on many of the highest summits of the Adirondacks, in alpine meadows sometimes adjacent to krummholz. It is also known at least historically from slightly lower sites on rock ledges and outcrops, and perhaps a bog, in cool microclimates in the high peaks region of the Adirondacks. There is also one disjunct extirpated population that was known from a maritime site on eastern Long Island (New York Natural Heritage Program 2007). Exposed, peaty and rocky areas (Haines and Vining 1998). On rocks (Gleason and Cronquist 1991). Arctic regions, peaty soils in more southern locations, alpine areas of northern New England and New York (Fernald 1970).

Associated Ecological Communities

  • Maritime bluff* (guide)
    A sparsely vegetated community that occurs on vertical exposures of unconsolidated material, such as small stone, gravel, sand, and clay, that is exposed to maritime forces, such as water, ice, or wind. * probable association but not confirmed.
  • Maritime grassland* (guide)
    A grassland community that occurs on rolling outwash plains of the glaciated portion of the Atlantic coastal plain, near the ocean and within the influence of offshore winds and salt spray. * probable association but not confirmed.
  • Maritime heathland* (guide)
    A dwarf shrubland community that occurs on rolling outwash plains and moraine of the glaciated portion of the Atlantic coastal plain, near the ocean and within the influence of onshore winds and salt spray. * probable association but not confirmed.
  • Open alpine community (guide)
    An open community consisting of a mosaic of sedge/dwarf shrub meadows, dwarf heath shrublands, small boggy depressions, and exposed bedrock covered with lichens and mosses. The open alpine community occurs above timberline (about 4,900 ft or 1,620 m) on the higher mountain summits and exposed ledges of the Adirondacks. The flora includes arctic-alpine species that are restricted (in New York) to these areas, as well as boreal species that occur in forests and bogs at lower elevations. The soils are thin and organic, primarily composed of peat derived from peat mosses (Sphagnum spp.) or black muck. The soils are often saturated because they can be recharged by atmospheric moisture.

Associated Species

  • Agrostis mertensii (northern bent)
  • Betula glandulosa (alpine birch, resin birch)
  • Carex bigelowii
  • Carex scirpoidea ssp. scirpoidea (Canadian single-spike sedge)
  • Diapensia lapponica var. lapponica
  • Empetrum eamesii ssp. atropurpureum
  • Geocaulon lividum (false toadflax)
  • Hierochloe alpina ssp. orthantha
  • Huperzia appressa (mountain firmoss)
  • Minuartia groenlandica
  • Prenanthes boottii
  • Prenanthes nana
  • Rhododendron groenlandicum (Labrador-tea)
  • Rhododendron lapponicum var. lapponicum
  • Salix uva-ursi (bearberry willow)
  • Sibbaldiopsis tridentata
  • Solidago leiocarpa (Cutler's alpine goldenrod)
  • Solidago simplex var. monticola
  • Trichophorum caespitosum
  • Vaccinium boreale (northern lowbush blueberry)
  • Vaccinium uliginosum (bog bilberry)

Range

New York State Distribution

In New York this species occurs predominately in the high peaks region of the Adirondacks. It is was also known historically from one population in Suffolk County, Long Island, but that population is believed to be extirpated. New York is at the southern edge of its range.

Global Distribution

Empetrum nigrum ssp. hermaphroditum occurs in the northern parts of Europe and Asia as well as Greenland and eastern North America, south to northern Minnesota, Michigan, the coast of Maine, the alpine areas of northern New England and New York, and formerly one disjunct on Long Island (Fernald 1970, Anderberg 1994, New York Natural Heritage Program 2007). Depending on the circumscription of this taxon it is also considered to occur in the arctic regions of western North America south to the alpine areas of northern California to southern Alberta (Fernald 1970).

Identification Comments

General Description

Black crowberry is a very low trailing shrub that makes an attractive dense ground cover in the exposed alpine areas where it occurs. Its twigs, at least when young, have hairs with glands on the tips. The evergreen leaves are short and needle-like with tiny glandular teeth along the margins. The leaves are mostly without hairs and spread or reflex back from the braches where they arise. The small and inconspicuous flowers occur in the axils of the leaves. The fruits are about .25 to .35 inches in diameter, black, and sometimes have a thin white waxy coating (Fernald 1970, Gleason and Cronquist 1991).

Identifying Characteristics

This species is a trailing woody evergreen shrub. The twigs and branchlets especially when young are minutely stipitate-glandular and are not densely white-tomentose or white-villose. The leaves are evergreen, needle-like, and stiff. The flowers are mostly bisexual. The drupes are black and glaucous.

Best Life Stage for Proper Identification

This species can be easily identified throughout the year when snow is not covering it, although, fruits make identification easier.

Similar Species

The other species of Empetrum (E. eamesii ssp. atropurpureum) that occurs in New York and can be present with E. nigrum ssp. hermaphroditum is superficially very similar. It differs in having twigs and brachlets white-tomentose or white-villous and not stipitate glandular, and drupes purple-black. Its new leaves have white hairs along the entire margin.

Harrimanella hypnoides is another alpine plant that is believed to be extirpated in New York. It perhaps could be mistaken for Empetrum nigrum ssp. hermaphroditum when vegetative due to its evergreen needle like leaves. It can be distinguished by its smaller size, its rough margined leaves that arise along the entire stem, and its showy, white, bell-shaped flowers at the tips of stems, which mature into dry capsules.

Best Time to See

This plant starts to have fruits in July and these can last into the fall. Therefore, the best time to survey for this species is from July through late October although it can be distinguished vegetatively anytime during the growing season.

  • Vegetative
  • Flowering
  • Fruiting

The time of year you would expect to find Black Crowberry vegetative, flowering, and fruiting in New York.

Black Crowberry Images

Taxonomy

Black Crowberry
Empetrum nigrum ssp. hermaphroditum (Lange ex Hagerup) Böcher

  • Kingdom Plantae
    • Phylum Anthophyta
      • Class Dicotyledoneae (Dicots)
        • Order Ericales
          • Family Empetraceae (Crowberry Family)

Additional Common Names

  • Curlew-berry

Synonyms

  • Empetrum hermaphroditum Lange ex Hagerup
  • Empetrum eamesii ssp. hermaphroditum (Lange ex Hagerup) D. Love
  • Empetrum nigrum var. hermaphroditum (Hagerup) T. Sørensen

Comments on the Classification

Empetrum nigrum L. sensu stricto was originally used in a broad sense to include North American, European and Asian plants. Hagerup (1927 in Anderberg 1994) transferred hermaphroditic, tetraploid plants to E. hermaphroditum. This included the North American plants that had previously been recognized as E. nigrum. Löve (1960 in Anderberg 1994) also transferred other hermaphroditic tetraploid plants from North America into E. hermaphroditum including E. eamesii sensu stricto and E. atropurpureum. The name E. eamesii took priority and the name E. eamesii ssp. hermaphroditum was used. Recognition that E. hermaphroditum is more closely related to E. nigrum than E. eamesii sensu stricto or E. atropurpureum, facilitated the transfer to E. nigrum as E. nigrum ssp. hermaphroditum. Anderberg's (1994) work supports this idea. More work will help to resolve at what rank (species or subspecies) the two taxa (E. nigrum sensu stricto and E. hermaphroditum) should be recognized. Gleason and Cronquist (1991) recognize E. hermaphroditum at the subspecific rank of variety: E. nigrum var. hermaphroditum (Hagerup) T. Sørensen. Li et al. (2002) show that the Empetraceae is monophyletic. Work by Judd and Kron (1993) indicate that the Empetraceae is derived from within Ericaceae and therefore if a broad Ericaceae concept is followed Empetraceae needs to be included for Ericaceae to be monophyletic. Therefore, they lump the Empetraceae into Ericaceae.

Additional Resources

Best Identification Reference

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.

Other References

Aiken, S.G., M.J. Dallwitz, L.L. Consaul, C.L. McJannet, L.J. Gillespie, R.L. Boles, G.W. Argus, J.M. Gillett, P.J. Scott, R. Elven, M.C. LeBlanc, A.K. Brysting and H. Solstad. 2003. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 29th April 2003. http://www.mun.ca/biology/delta/arctic

Anderberg, A.A. 1994. Phylogeny of the Empetraceae, with Special Emphasis on Character Evolution in the Genus Empetrum. Systematic Botany 19: 35-46.

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

Haines, A. and T.F. Vining. 1998. Flora of Maine, A Manual for Identification of Native and Naturalized Vascular Plants of Maine. V.F.Thomas Co., Bar Harbor, Maine.

Holmgren, Noel. 1998. The Illustrated Companion to Gleason and Cronquist's Manual. Illustrations of the Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York.

Judd, W.S.and K.A. Kron. 1993. Circumscription of Ericaceae (Ericales) as Determined by Preliminary Cladistic Analyses Based on Morphological, Anatomical, and Embryological Features. Brittonia 45: 99-114.

Li, J., J. Alexander III, T. Ward, P.D. Tredici, and R. Nicholson. 2002. Phylogenetic relationships of Empetraceae inferred from sequences of chloroplast gene matK and nuclear ribosomal DNA its region. Molecular Phylogenetics and Evolution 25: 306-315.

New York Natural Heritage Program. 2010. Biotics database. New York Natural Heritage Program. New York State Department of Environmental Conservation. Albany, NY.

New York Natural Heritage Program. 2019. New York Natural Heritage Program Databases. Albany, NY.

Reschke, Carol. 1990. Ecological communities of New York State. New York Natural Heritage Program, New York State Department of Environmental Conservation. Latham, NY. 96 pp. plus xi.

Waller, J. and M.J. DiGregorio. 1997. New England's Mountain Flowers. A High Country Heritage. Mountain Press Publishing Company, Missoula, Montana.

Weldy, T. and D. Werier. 2010. New York flora atlas. [S.M. Landry, K.N. Campbell, and L.D. Mabe (original application development), Florida Center for Community Design and Research http://www.fccdr.usf.edu/. University of South Florida http://www.usf.edu/]. New York Flora Association http://newyork.plantatlas.usf.edu/, Albany, New York

Links

About This Guide

Information for this guide was last updated on: January 31, 2008

Please cite this page as:
New York Natural Heritage Program. 2019. Online Conservation Guide for Empetrum nigrum ssp. hermaphroditum. Available from: https://guides.nynhp.org/black-crowberry/. Accessed September 23, 2019.

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