Wiry Witch Grass

Panicum flexile (Gattinger) Scribn.

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Class
Monocotyledoneae (Monocots)
Family
Poaceae (Grass 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
G5
Secure globally - Common in the world; widespread and abundant (but may be rare in some parts of its range).

Summary

State Ranking Justification

There are 21 known occurrences and 17 are good to excellent. More occurrences are expected in its range since it probably occurs in many small wetlands that have not been inventoried.

Short-term Trends

Approximately 1000 plants.

Conservation and Management

Habitat

Habitat

In New York, Wiry Panic Grass has been found in a diversity of open, mostly calcareous habitats, both wet and dry, including fens and wet meadows, alvar and calcareous pavement barrens, and cliffs (New York Natural Heritage Program 2011). Fens and other calcareous wetlands, in dry, calcareous or mafic rock barrens, and in open woodlands, especially on limestone derived soils (FNA 2007). Dry fields, moist meadows, banks, and swales (Rhoads and Block 2000). Dry to moist, chiefly calcareous ledges, sands and moors (Fernald 1970). Damp sandy or gravelly, usually calcareous, shores and marsh places (Voss 1972).

Associated Ecological Communities

  • Alvar pavement grassland (guide)
    This community consists of exposed, flat limestone or dolostone pavement with grassy or mossy patches interspersed throughout. Some examples may be solely grassland with no pavement.
  • Calcareous cliff community (guide)
    A community that occurs on vertical exposures of resistant, calcareous bedrock (such as limestone or dolomite) or consolidated material; these cliffs often include ledges and small areas of talus.
  • Calcareous shoreline outcrop (guide)
    A community that occurs along the shores of lakes and streams on outcrops of calcareous rocks such as limestone and dolomite. The vegetation is sparse; most plants are rooted in rock crevices.
  • Gravel mine
    An excavation in a gravel deposit from which gravel has been removed. Often these are dug into glacial deposits such as eskers or kames. Vegetation may be sparse if the mine is active; there may be substantial vegetative cover if the mine has been inactive for several years. Near-vertical slopes are used by bank swallows for nesting sites.
  • Marl fen (guide)
    A wetland that occurs on a bed of marl. Marl is a whitish substance that is deposited from water that has a lot of calcium dissolved in it. The whitish substance is calcium carbonate, people used to harvest marl to lime agricultural fields. The marl substrate is always saturated, may be flooded, and has a very high pH, generally greater than 7.5. The main source of water is always groundwater. The plants are often sparse and stunted. Marl fens may occur as small patches within a rich graminoid fen.
  • Mowed roadside/pathway
    A narrow strip of mowed vegetation along the side of a road, or a mowed pathway through taller vegetation (e.g., meadows, old fields, woodlands, forests), or along utility right-of-way corridors (e.g., power lines, telephone lines, gas pipelines). The vegetation in these mowed strips and paths may be dominated by grasses, sedges, and rushes; or it may be dominated by forbs, vines, and low shrubs that can tolerate infrequent mowing.
  • Rich graminoid fen (guide)
    A wetland of mostly grasses usually fed by water from highly calcareous springs or seepage. These waters have high concentrations of minerals and high pH values, generally from 6.0 to 7.8. Plant remains do not decompose rapidly and these grasses usually grow on older, undecomposed plant parts.

Associated Species

  • Abietinella abietina
  • Agalinis paupercula (small-flowered agalinis)
  • Agrostis hyemalis (southern tickle grass)
  • Allium schoenoprasum (chives)
  • Andropogon gerardii
  • anticlea elegans
  • Aquilegia canadensis (wild columbine, red columbine)
  • Argentina anserina
  • Asplenium trichomanes
  • Bromus kalmii (Kalm's brome)
  • Bryum pseudotriquetrum
  • Campanula rotundifolia (hare-bell)
  • Carex eburnea (bristle-leaved sedge)
  • Carex viridula
  • Centaurium pulchellum (branching centaury)
  • Cladonia pocillum
  • Comandra umbellata
  • Cyperus strigosus (false yellow nut sedge)
  • Deschampsia cespitosa (tufted hair grass)
  • Dichanthelium acuminatum
  • Eleocharis tenuis
  • Equisetum variegatum
  • Euphrasia stricta (upright eye-bright)
  • Gentianopsis crinita (common fringed gentian)
  • Hedeoma pulegioides (American-pennyroyal)
  • Hypericum perforatum
  • Juniperus horizontalis (creeping juniper)
  • Lobelia kalmii (Kalm's lobelia)
  • Lythrum salicaria (purple loosestrife)
  • Muhlenbergia glomerata (spike muhly)
  • Oligoneuron album
  • Packera paupercula (balsam groundsel)
  • Pellaea atropurpurea (purple cliff-brake)
  • Pellaea glabella
  • Poa compressa (flat-stemmed blue grass, Canada blue grass)
  • Polygala verticillata (whorled milkwort)
  • Potentilla norvegica (ternate-leaved cinquefoil)
  • Pycnanthemum virginianum (Virginia mountain-mint)
  • Saxifraga virginiensis
  • Scutellaria parvula
  • Solidago nemoralis
  • Sorghastrum nutans (Indian grass)
  • Spiranthes cernua (nodding ladies'-tresses)
  • Sporobolus neglectus (small dropseed)
  • Sporobolus vaginiflorus
  • Thuja occidentalis (northern white cedar, arbor vitae)
  • Trichostema brachiatum (false pennyroyal)

Range

New York State Distribution

Most populations of this plant are located near the St. Lawrence Seaway, the southern tip of Lake Champlain, and western New York. This grass is probably more common than its current documentation depicts. All calcareous wetlands should be thoroughly searched for this plant.

Identification Comments

Identifying Characteristics

Distinguishing characteristics: slender annual; stem erect, 20-40 (-70) cm tall, and branched from the base; winter rosettes not formed; blades of the stem and basal leaves similar, stem blades erect; sheaths papillose-hispid; panicle highly branched, 5-30 cm long, usually less than half as broad, narrowly ellipsoid with ascending branches; spikelets 3-3.5 mm long, solitary at the tips of the branchlets, mostly on long peduncles, smooth; pulvini of the lower panicle branches glabrous.

Best life stage for ID: mature plants in fruit. / Characters needed to ID: stems with leaves and fruits.

Best Life Stage for Proper Identification

Specimens with matue fruit are needed for identification.

Similar Species

Panicum species are often difficult for people to identify. For someone who knows Panicum species well, Panicum flexile is most closely aligned to Panicum capillare. Panicum capillare has a broadly ovoid terminal panicle as much as ½the height of the plant, stems 40-100 cm tall, and the pulvini (a swelling at the base of the petiole) of the lower panicle branches hispid.

Best Time to See

Panicum flexile is best seen when mature fruit are present, from July to November.

  • Fruiting

The time of year you would expect to find Wiry Witch Grass fruiting in New York.

Taxonomy

Wiry Witch Grass
Panicum flexile (Gattinger) Scribn.

  • Kingdom Plantae
    • Phylum Anthophyta
      • Class Monocotyledoneae (Monocots)
        • Order Cyperales
          • Family Poaceae (Grass Family)

Additional Common Names

  • Wiry Panic Grass

Additional Resources

References

Flora of North America Editorial Committee. 2007a. Flora of North America North of Mexico. Vol. 24. Magnoliophyta: Commelinidae (in part): Poaceae, part 1. Oxford Univ. Press, New York. xxviii + 911 pp.

New York Natural Heritage Program. 2024. New York Natural Heritage Program Databases. Albany, NY.

Links

About This Guide

Information for this guide was last updated on: August 9, 2011

Please cite this page as:
New York Natural Heritage Program. 2024. Online Conservation Guide for Panicum flexile. Available from: https://guides.nynhp.org/wiry-panic-grass/. Accessed March 28, 2024.