Calochortus howellii - S. Wats.
Howell's Mariposa Lily
Taxonomic Status: Accepted
Related ITIS Name(s): Calochortus howellii S. Wats. (TSN 42850)
Unique Identifier: ELEMENT_GLOBAL.2.132670
Element Code: PMLIL0D0K0
Informal Taxonomy: Plants, Vascular - Flowering Plants - Lily Family
 
Kingdom Phylum Class Order Family Genus
Plantae Anthophyta Monocotyledoneae Liliales Liliaceae Calochortus
Check this box to expand all report sections:
Concept Reference
Help
Concept Reference: Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Concept Reference Code: B94KAR01HQUS
Name Used in Concept Reference: Calochortus howellii
Taxonomic Comments: Distinct species, 1 of 11 Oregon species in this genus.
Conservation Status
Help

NatureServe Status

Global Status: G3
Global Status Last Reviewed: 05Feb2004
Global Status Last Changed: 05Feb2004
Rounded Global Status: G3 - Vulnerable
Reasons: Although endemic to southwestern Oregon and restricted to serpentine substrates, which are mined for gold, chromium, and nickel, this species can be locally abundant with some large population sizes. The number of known occurrences is about 50; total plants numbers at least 65,000.
Nation: United States
National Status: N3

U.S. & Canada State/Province Status
United States Oregon (S3)

Other Statuses

NatureServe Global Conservation Status Factors

Range Extent Comments: Known only from southwestern Oregon, Douglas and Josephine Counties, Oregon.

Number of Occurrences: 21 - 80
Number of Occurrences Comments: There are about 50 known occurrences.

Population Size Comments: Plant numbers total more than 65,000.

Overall Threat Impact Comments: Threatened by urban growth, livestock grazing, mining of the mineral rich serpentine substrate, horticultural collecting, fire suppression methods.

Short-term Trend: Relatively Stable (<=10% change)
Short-term Trend Comments: Population numbers in general appear to be stable.

Intrinsic Vulnerability Comments: Plants can be fairly resistant to natural disturbance.

Other NatureServe Conservation Status Information

Distribution
Help
Global Range: Known only from southwestern Oregon, Douglas and Josephine Counties, Oregon.

U.S. States and Canadian Provinces
Color legend for Distribution Map

U.S. & Canada State/Province Distribution
United States OR

Range Map
No map available.


U.S. Distribution by County Help
State County Name (FIPS Code)
OR Curry (41015), Josephine (41033)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
17 Illinois (17100311)+
18 Smith (18010101)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
Help
Basic Description: A perennial herb with a slender stem, 3-4 dm tall, and a single leaf arising from a bulb. Showy white flowers bloom from May to July.
General Description: This lily-like plant has an erect, slender bloom stalk that grows up to 18 inches tall (4.5 dm) with 1 or 2 wide upright, bell-shaped, pure white flowers (or white with a greenish tinge) with brownish bases which are less than an inch long (2.5 cm). Dense white to brownish to greenish hairs cover the dark base of the petals. Sepals are white and narrow. The capsule is elliptic, erect, less than 3/4 of an inch long. A single basal leaf sometimes longer that the flower stalk and about 1/3 inch wide (10mm) is densely hairy on the upper surface in the middle.
Technical Description: Erect, slender, 3-4 dm high: leaf solitary, sometimes surpassing the inflorescence, 5-10 mm wide, tomentose on the upper surface, the middle of the stem with a narrow bract 2-5 cm long; flowers usually 1 or 2, on erect pedicels 5-10 cm long, broadly campanulate; sepals 16-20 mm long, ovate, acuminate, broadly scarious-margined; petals broadly obovate, 2.5 cm long, creamy or slightly greenish-tinged, the apex erose-denticulate, the outer half with sparse whitish hairs, the basal portion more densely purple-hairy, the gland partly covered with short greenish hairs; anthers oblong, 7 mm long, short-apiculate; capsule elliptic, 18-20 mm long. (Peck 1961)
Habitat Comments: Serpentine outcrops at lower or middle elevations. Always on dry slopes with buckbrush (Ceanothus cuneatus), sticky manzanita (Arctostaphylos viscida), or, rarely, Brewer oak (Quercus breweri) or sparse Jeffrey pine (Pinus jeffreyi).
Economic Attributes Not yet assessed
Help
Management Summary Not yet assessed
Help
Population/Occurrence Delineation Not yet assessed
Help
Population/Occurrence Viability
Help
U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
Help
Authors/Contributors
Help
NatureServe Conservation Status Factors Edition Date: 28Oct2002
NatureServe Conservation Status Factors Author: Vrilaks (2002); Roth, E., rev. Kagan/Vrilakas/Maybury (1996)

Botanical data developed by NatureServe and its network of natural heritage programs (see Local Programs), The North Carolina Botanical Garden, and other contributors and cooperators (see Sources).

References
Help
  • Flora of North America Editorial Committee. 2002a. Flora of North America North of Mexico. Vol. 26. Magnoliophyta: Liliidae: Liliales and Orchidales. Oxford Univ. Press, New York. xxvi + 723 pp.

  • Fredricks, N.A. 1986. Calochortus howellii: Ecology of a rare serpentine endemic and comparison with the new species, C. umpquaensis (Liliaceae). M.S. thesis, Oregon State University, Corvallis.

  • Fredricks, N.A. 1989. Morphological comparison of Calochortus howellii and a new species from southwestern Oregon, C. umpquaensis (Liliaceae). Systematic Botany 14(1):7-15.

  • Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.

  • Meinke, R.J. 1982. Threatened and Endangered Vascular Plants of Oregon: An Illustrated Guide. U.S. Fish and Wildlife Service, Region 1, Portland, Oregon. 326 pp.

Use Guidelines & Citation

Use Guidelines and Citation

The Small Print: Trademark, Copyright, Citation Guidelines, Restrictions on Use, and Information Disclaimer.

Note: All species and ecological community data presented in NatureServe Explorer at http://explorer.natureserve.org were updated to be current with NatureServe's central databases as of November 2016.
Note: This report was printed on

Trademark Notice: "NatureServe", NatureServe Explorer, The NatureServe logo, and all other names of NatureServe programs referenced herein are trademarks of NatureServe. Any other product or company names mentioned herein are the trademarks of their respective owners.

Copyright Notice: Copyright © 2017 NatureServe, 4600 N. Fairfax Dr., 7th Floor, Arlington Virginia 22203, U.S.A. All Rights Reserved. Each document delivered from this server or web site may contain other proprietary notices and copyright information relating to that document. The following citation should be used in any published materials which reference the web site.

Citation for data on website including State Distribution, Watershed, and Reptile Range maps:
NatureServe. 2017. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org. (Accessed:

Citation for Bird Range Maps of North America:
Ridgely, R.S., T.F. Allnutt, T. Brooks, D.K. McNicol, D.W. Mehlman, B.E. Young, and J.R. Zook. 2003. Digital Distribution Maps of the Birds of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Bird Range Maps of North America:
"Data provided by NatureServe in collaboration with Robert Ridgely, James Zook, The Nature Conservancy - Migratory Bird Program, Conservation International - CABS, World Wildlife Fund - US, and Environment Canada - WILDSPACE."

Citation for Mammal Range Maps of North America:
Patterson, B.D., G. Ceballos, W. Sechrest, M.F. Tognelli, T. Brooks, L. Luna, P. Ortega, I. Salazar, and B.E. Young. 2003. Digital Distribution Maps of the Mammals of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Mammal Range Maps of North America:
"Data provided by NatureServe in collaboration with Bruce Patterson, Wes Sechrest, Marcelo Tognelli, Gerardo Ceballos, The Nature Conservancy-Migratory Bird Program, Conservation International-CABS, World Wildlife Fund-US, and Environment Canada-WILDSPACE."

Citation for Amphibian Range Maps of the Western Hemisphere:
IUCN, Conservation International, and NatureServe. 2004. Global Amphibian Assessment. IUCN, Conservation International, and NatureServe, Washington, DC and Arlington, Virginia, USA.

Acknowledgement Statement for Amphibian Range Maps of the Western Hemisphere:
"Data developed as part of the Global Amphibian Assessment and provided by IUCN-World Conservation Union, Conservation International and NatureServe."

NOTE: Full metadata for the Bird Range Maps of North America is available at:
http://www.natureserve.org/library/birdDistributionmapsmetadatav1.pdf.

Full metadata for the Mammal Range Maps of North America is available at:
http://www.natureserve.org/library/mammalsDistributionmetadatav1.pdf.

Restrictions on Use: Permission to use, copy and distribute documents delivered from this server is hereby granted under the following conditions:
  1. The above copyright notice must appear in all copies;
  2. Any use of the documents available from this server must be for informational purposes only and in no instance for commercial purposes;
  3. Some data may be downloaded to files and altered in format for analytical purposes, however the data should still be referenced using the citation above;
  4. No graphics available from this server can be used, copied or distributed separate from the accompanying text. Any rights not expressly granted herein are reserved by NatureServe. Nothing contained herein shall be construed as conferring by implication, estoppel, or otherwise any license or right under any trademark of NatureServe. No trademark owned by NatureServe may be used in advertising or promotion pertaining to the distribution of documents delivered from this server without specific advance permission from NatureServe. Except as expressly provided above, nothing contained herein shall be construed as conferring any license or right under any NatureServe copyright.
Information Warranty Disclaimer: All documents and related graphics provided by this server and any other documents which are referenced by or linked to this server are provided "as is" without warranty as to the currentness, completeness, or accuracy of any specific data. NatureServe hereby disclaims all warranties and conditions with regard to any documents provided by this server or any other documents which are referenced by or linked to this server, including but not limited to all implied warranties and conditions of merchantibility, fitness for a particular purpose, and non-infringement. NatureServe makes no representations about the suitability of the information delivered from this server or any other documents that are referenced to or linked to this server. In no event shall NatureServe be liable for any special, indirect, incidental, consequential damages, or for damages of any kind arising out of or in connection with the use or performance of information contained in any documents provided by this server or in any other documents which are referenced by or linked to this server, under any theory of liability used. NatureServe may update or make changes to the documents provided by this server at any time without notice; however, NatureServe makes no commitment to update the information contained herein. Since the data in the central databases are continually being updated, it is advisable to refresh data retrieved at least once a year after its receipt. The data provided is for planning, assessment, and informational purposes. Site specific projects or activities should be reviewed for potential environmental impacts with appropriate regulatory agencies. If ground-disturbing activities are proposed on a site, the appropriate state natural heritage program(s) or conservation data center can be contacted for a site-specific review of the project area (see Visit Local Programs).

Feedback Request: NatureServe encourages users to let us know of any errors or significant omissions that you find in the data through (see Contact Us). Your comments will be very valuable in improving the overall quality of our databases for the benefit of all users.