Jepson eFlora: Taxon page
Vascular Plants of California
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Isoetes orcuttii

Higher Taxonomy
Family: IsoetaceaeView Description 
Habit: Perennial herb, aquatic to terrestrial. Stem: buried, corm-like, 2--3-lobed, corky, brown. Leaf: simple, in grass-like tufts, spirally arranged on stem top, erect to spreading, < 30 cm, linear above base. Sporangia: solitary, embedded in wide leaf base, < 1 cm, +- covered by a translucent membrane, male or female; male spores > 10000, < 0.045 mm, +- bean-shaped, gray or brown in mass; female spores 20--200, 0.2--0.7 mm, spheric, white, +- smooth, ridged, tubercled, or prickly.
Genera In Family: 1 genus, 200+ species: worldwide.
eFlora Treatment Author: W. Carl Taylor & Jon E. Keeley
Scientific Editor: Alan R. Smith, Thomas J. Rosatti.
Genus: IsoetesView DescriptionDichotomous Key

Common Name: QUILLWORT

Etymology: (Greek: evergreen, from habit of some species) Note: Perhaps most poorly known lycophyte genus. Mature female spores, found in decaying leaf bases or soil, critical for identification, as are hand lens for texture when dry, microscope with micrometer for size. Hybrids (spores of variable size, shape) common between aquatic species, making them less distinct.
Isoetes orcuttii A.A. Eaton
Habit: Plant becoming terrestrial. Leaf: deciduous, generally < 8 cm, < 1 mm wide at middle, soft, flexible, tapered to tip, bright green; base white to +- brown, outermost fertile, often surrounded by several black scales. Sporangia: membrane covering > 75%; male spores 0.02--0.025 mm, brown in mass; female spores 0.2--0.4 mm, +- shiny, +- smooth. Chromosomes: 2n=22.
Ecology: Vernal pools; Elevation: < 1700 m. Bioregional Distribution: NCoRI, (Howell Mtn, Napa Co.), CaR, n&c SNF, SNH, GV, CCo, SnFrB, SCo, PR; Distribution Outside California: southwestern Oregon; Baja California. Note: Spores mature spring.
Jepson eFlora Author: W. Carl Taylor & Jon E. Keeley
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)

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Citation for this treatment: W. Carl Taylor & Jon E. Keeley 2012, Isoetes orcuttii, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on February 28, 2024.

Citation for the whole project: Jepson Flora Project (eds.) 2024, Jepson eFlora,, accessed on February 28, 2024.

Isoetes orcuttii
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©2018 Barry Rice
Isoetes orcuttii
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©2004 Carol W. Witham
Isoetes orcuttii
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©2022 Neal Kramer
Isoetes orcuttii
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©2022 Neal Kramer
Isoetes orcuttii
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©2012 Gary A. Monroe

More photos of Isoetes orcuttii
in CalPhotos

Geographic subdivisions for Isoetes orcuttii:
NCoRI, (Howell Mtn, Napa Co.), CaR, n&c SNF, SNH, GV, CCo, SnFrB, SCo, PR
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map of distribution 1
(Note: any qualifiers in the taxon distribution description, such as 'northern', 'southern', 'adjacent' etc., are not reflected in the map above, and in some cases indication of a taxon in a subdivision is based on a single collection or author-verified occurence).


Data provided by the participants of the  Consortium of California Herbaria.
View all CCH records
All markers link to CCH specimen records. The original determination is shown in the popup window.
Blue markers indicate specimens that map to one of the expected Jepson geographic subdivisions (see left map). Purple markers indicate specimens collected from a garden, greenhouse, or other non-wild location.
Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues.

CCH collections by month

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa, if there are more than 1 infraspecific taxon in CA.
Blue line denotes eFlora flowering time (fruiting time in some monocot genera).