Juncus ambiguus flowers and fruit Deborah Morrison

Juncus ambiguus flowers and fruit
Deborah Morrison

Class
Monocotyledoneae (Monocots)
Family
Juncaceae (Rush Family)
State Protection
Endangered
Federal Protection
Not Listed
State Conservation Status Rank
SH
Global Conservation Status Rank
G5

Summary

Did you know?

This rush is hard to distinguish from the closely related Juncus bufonius or toad rush and this difficulty is reflected in its species name.

State Ranking Justification

There is one existing population that has not been surveyed in detail. There is also one historical locality.

Short-term Trends

More surveys are needed to understand short-term trends.

Long-term Trends

More surveys are needed to understand long-term trends.

Conservation and Management

Threats

More surveys are needed to understand current threats.

Conservation Strategies and Management Practices

More surveys are needed to understand management needs.

Research Needs

Research is needed to determine habitat preference and propagation needs to augment existing populations.

Habitat

Habitat

The only known occurrence in New York turned up in a brackish mitigation wetland with shrubs and trees between a road interchange and the Long Island Railroad. (New York Natural Heritage Program 2012). Salt-loving, occurring along the coast on mud and sand flats above high tide and one margins of saline and brackish lakes. Also occurring inland on bare mud and disturbed ground near salt-works, in roadside ditches, and on highly basic substrates (Clemants 1990).

Associated Ecological Communities

  • Brackish meadow* (guide)

Associated Species

  • Persicaria hydropiperoides (mild water-pepper)
  • Phragmites australis (old world reed grass, old world phragmites)
  • Symphyotrichum subulatum

Range

New York State Distribution

This species is known only from Suffolk County, Long Island.

Global Distribution

In the East this wetland herb occurs on the Atlantic coastal plain from Nova Scotia and Maine south to Long Island where it is rare. There are scattered inland populations in Pennsylvania south to Georgia, Alabama, and Tennessee. It also occurs in scattered states of the western US to California and Alaska and in Canada from Manitoba west to British Columbia.

Best Places to See

  • Connetquot State Park (Suffolk County)

Identification Comments

General Description

Doubtful toad rush is a short, soft, annual rush that grows erect or ascending from a branching base up to about 3 dm tall. The leaves arise from the base and the stem and are very narrow, up to about 1.1 mm wide and flat or channeled. The inflorescence is contracted and makes up usually more than half of the stem. The single flowers are scattered among it in the axils of small leafy bracts. Each flower also has a pair of broad, whitish, rough bracteoles at the bottom. The tepals are narrow with a greenish midvein and whitish margins. They are about the same size and 3-6 millimeters long. The inner tepals are mostly rounded, occasionally acute, and often emarginate and mucronate at the tip. The capsules are flattened on the top and as long as or longer than the inner tepals. The seeds are 0.3-0.6 mm long and pointed at each end.

Best Life Stage for Proper Identification

The best time to identify this plant is in fruit.

Similar Species

The much more common and widespread Juncus bufonius has inner tepals that are acute to acuminate, the inflorescence is open and not contracted, and the capsule is acute to subacute, while being clearly shorter than the inner tepals. These species are the only ones in the genus that are soft annuals with single flowers in an inflorescence that makes up most of the plant.

Best Time to See

The fruits are visible from July through early November.

  • Fruiting

The time of year you would expect to find Seaside Toad Rush fruiting in New York.

Seaside Toad Rush Images

Taxonomy

Seaside Toad Rush
Juncus ranarius Songeon & E.P. Perrier

  • Kingdom Plantae
    • Phylum Anthophyta
      • Class Monocotyledoneae (Monocots)
        • Order Juncales
          • Family Juncaceae (Rush Family)

Additional Common Names

  • Toad-rush

Synonyms

  • Juncus bufonius var. halophilus Buch. & Fern.
  • Juncus bufonius ssp. ranarius (Song. & Perr.) Hiit.
  • Juncus bufonius var. ranarius (Perrier & Song.) Hayek
  • Juncus ambiguus Guss.

Additional Resources

Best Identification Reference

Flora of North America Editorial Committee. 2000. Flora of North America north of Mexico. Vol. 22. Magnoliophyta: Alismatidae, Arecidae, Commelinidae (in part), and Zingiberidae. Oxford Univ. Press, New York. xxiii + 352 pp.

Other References

Clemants, Steven E. 1990. Juncaceae (rush family) of New York State. Contributions to a flora of New York State VII Richard S. Mitchell, ed. New York State Museum Bulletin No. 475. 67 pp.

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

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.

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.

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

This guide was authored by: Stephen M. Young

Information for this guide was last updated on: September 6, 2012

Please cite this page as:
New York Natural Heritage Program. 2019. Online Conservation Guide for Juncus ranarius. Available from: https://guides.nynhp.org/seaside-toad-rush/. Accessed March 20, 2019.

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