Search Field Guide
Advanced Search
MT Gov Logo
Montana Field Guide

Montana Field Guides

Howell's Quillwort - Isoetes howellii

No photos are currently available
If you have a high quality photo of this species, are confident in the identification, and would like to submit it for inclusion on the Montana Field Guide, please send it to us using our online photo submission tool.


Image Copyright and Usage Information
Species of Concern
Native Species

Global Rank: GNR
State Rank: S3
(see State Rank Reason below)
State Threat Score: No Known Threats
CCVI: Less Vulnerable
C-value: 8


Agency Status
USFWS:
USFS:
BLM:


 

External Links

State Rank Reason (see State Rank above)
Isoetes howellii is known from about 5 locations in Northwestern Montana. Based on limited information threats appear to be minimal, but survey work to document locations, population sizes, and threats is greatly needed.
  • Details on Status Ranking and Review
    Howell's Quillwort (Isoetes howellii) Conservation Status Review
    Review Date = 09/22/2018
    View State Conservation Rank Criteria
    Range Extent

    ScoreD - 1,000-5,000 sq km (~400-2,000 sq mi)

    Area of Occupancy

    ScoreC - 3-5 4-km2 grid cells

    Number of Populations

    ScoreA - 1 - 5

    Number of Occurrences or Percent Area with Good Viability / Ecological Integrity

    ScoreB - Very few (1-3) occurrences with excellent or good viability or ecological integrity

    Environmental Specificity

    ScoreB - Narrow. Specialist or community with key requirements common

    Threats

    ScoreD - Low

    CommentNo known threats.

 
General Description
PLANTS: Semi-aquatic to aquatic. Usually at least 10 cm tall.

LEAVES: Leaves up to 25 mm long and often black near the base (Lesica et al. 2012). Leaves thin and soft, light green, deciduous, and gradually tapering from near the base to a long, very slender tip. The hyaline leaf margins extend for 1-5 cm above the sporangia.

INFLORESCENCE: Sporangia wall streaked to completely brown. Megaspores about 0.3-0.45 mm wide, smooth or tuberculate but not spiny.

Species Range
Montana Range Range Descriptions

Native
 


Range Comments
In MT only known from Flathead, Glacier, Lake and Missoula counties; BC to CA, east to ID and MT (Lesica et al. 2012).

Observations in Montana Natural Heritage Program Database
Number of Observations: 5

(Click on the following maps and charts to see full sized version) Map Help and Descriptions
Relative Density

Recency

 

(Observations spanning multiple months or years are excluded from time charts)



Habitat
In and around ponds, lakes and sloughs where water recedes; valleys (Lesica et al. 2012).
Predicted Suitable Habitat Model

This species has a Predicted Suitable Habitat Model available.

To learn how these Models were created see mtnhp.org/models

Ecology
Plants are often unearthed by waterfowl, and can be found floating (Lesica et al. 2012).

Reproductive Characteristics
Plants collected early in the growing season may have immature spores that cannot be used for identification (Lesica et al. 2012).

Threats or Limiting Factors
STATE THREAT SCORE REASON
Threat impact not assigned because threats are not known (MTNHP Threat Assessment 2021).

References
  • Literature Cited AboveLegend:   View Online Publication
    • Lesica, P., M.T. Lavin, and P.F. Stickney. 2012. Manual of Montana Vascular Plants. Fort Worth, TX: BRIT Press. viii + 771 p.
  • Additional ReferencesLegend:   View Online Publication
    Do you know of a citation we're missing?
    • Garrett, P.A. 1983. Relationships between benthic communities, land use, chemical dynamics, and trophic state in Georgetown Lake. Ph.D. Dissertation. Bozeman, MT: Montana State University. 136 p.
    • Lesica, P., M.T. Lavin, and P.F. Stickney. 2022. Manual of Montana Vascular Plants, Second Edition. Fort Worth, TX: BRIT Press. viii + 779 p.
  • Web Search Engines for Articles on "Howell's Quillwort"
Login Logout

Take us with you! PDF icon

Look for this PDF icon as you search and browse.  Click it to build a custom PDF with species shown on that page or for all the species within that taxonomic level.  To create your own list of species, use the PDF Creator tool at the bottom of the Advanced Search page.

Here's some links if you want to download a whole group.

Mammals
Birds
Reptiles
Amphibians
Fish
Invertebrates
Butterflies / Moths
Dragonflies / Damselflies
Ferns and allies
Conifers
Flowering Plants (Dicots)
Flowering Plants (Monocots)
Bryophytes
Lichens
Ecological Systems
Noxious Weeds
Citation for data on this website:
Howell's Quillwort — Isoetes howellii.  Montana Field Guide.  .  Retrieved on , from