Phacelia denticulata
Author: Osterhout


Rocky Mountain phacelia


Hydrophyllaceae (Waterleaf Family)

Close up of Phacelia denticulata by Crystal Strouse.
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Close up of Phacelia denticulata by Crystal Strouse.
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Close up of Phacelia denticulata by Crystal Strouse.
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Close up of Phacelia denticulata by Rich Scully.
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Ranks and Status

Global rank: G3
State rank: SU
Federal protection status: None
State protection status: None

[+] Description and Phenology

Phacelia denticulata by Patricia Greenberg.
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General description: Taprooted annuals, 0.5-5.4 dm tall. Stems are bristly and glandular-stipitate. Leaves are 1-7.5 cm long, pinnately cleft or divided. Flowers light blue, the lobes denticulate. Stamens included (not exserted) in flowers (Ackerfield 2015).

Look Alikes: Distinguished from other Colorado Phacelia species by it's annual habit, light blue flowers, denticulate corolla lobes, and stamens not exserted (Ackerfield 2015).

Phenology: Flowers June-July.  Flowering and Fruiting June-September (Colorado Natural Heritage Program 2012).

[+] Habitat

Habitat of Phacelia denticulata by Crystal Strouse.
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Habitat of Phacelia denticulata by Crystal Strouse.
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Habitat of Phacelia denticulata by Rich Scully.
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In Colorado, this species has been found in sandy and rocky soils, typically in lightly disturbed areas such as loose soil on the sides of recently constructed trails, or along gullies. It has also been found on steep forested mountainsides with boulders and rocky outcrops. Dominant plants associated with this species are Pseudotsuga menziesii, Pinus ponderosa, Cercocarpus montanus, Hesperostipa neomexicana, Achnatherum hymenoides, and Chondrosum gracile.  Other associated species include Artemisia frigida, Phacelia alba, Eriogonum umbellatum, Opuntia polyacantha, Krascheninnikovia lanata, Muhlenbergia montanaQuercus gambelii, and  Danthonia parryi.

Elevation Range: 5,500 - 10,000 feet (1,676 - 3,048 meters)

[+] Distribution

Distribution of Phacelia denticulata in Colorado according to mapped land ownership/management boundaries (CNHP 2015, COMaP v9).
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Distribution of Phacelia denticulata in Colorado.
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Colorado endemic: No
Global range: Regional endemic of southeastern Wyoming, central Colorado, and northeastern New Mexico.
State range: Known from Boulder, Clear Creek, Douglas, El Paso, Las Animas, Larimer and Park Counties.

[+] Threats and Management Issues

Primary land use in the immediate vicinity of the occurrences appears to be non-motorized recreation. Weeds, and trail and road maintenence and contruction could become problematic at some locations. Location information lacks specificitiy in many cases, so overall land ownership/management patterns are unclear.  

[+] References

    • Ackerfield, J. 2015. Flora of Colorado. Brit Press, Botanical Research Institute of Texas, Fort Worth, TX. 818 pp.
    • Beardsley, M. and D. A. Steingraeber. 2013. Population dynamics, rarity and risk of extirpation for populations of Mimulus gemmiparus (budding monkeyflower) on National Forests of Colorado. A research report submitted to the USFS Forest Service. Arapaho and Roosevelt National Forets and Pawnee National Grassland. pp 17. Accessed online on May 11 at: http://www.r5.fs.fed.us/wildflowers/Rare_Plants/profiles/Critically_Imperiled/mimulus_gemmiparus/ documents/USFS_MimulusStatusReport2013.pdf
    • Harrington, H.D. 1954. Manual of the plants of Colorado. Sage Press, Chicago. 666 pp.
    • 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.
    • Weber, W. A. and R. C. Wittmann. 2012. Colorado Flora, Eastern Slope, A Field Guide to the Vascular Plants, Fourth Edition. Boulder, Colorado. 555 pp.
    • Weber, W. A. and R. C. Wittmann. 2012. Colorado Flora, Western Slope, A Field Guide to the Vascular Plants, Fourth Edition. Boulder, Colorado. 532 pp.

Last Updated

2015-07-31