Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): M. E. McIntosh; L. A. McDade; A. E. Boyd; P. D. Jenkins
    Date: 2007
    Source: In: Barlow-Irick, P.; Anderson, J.; McDonald, C., tech eds. Southwestern rare and endangered plants: Proceedings of the Fourth Conference; March 22-26, 2004; Las Cruces, New Mexico. Proceedings. RMRS-P-48CD. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 77-82
    Publication Series: Proceedings (P)
    Station: Rocky Mountain Research Station
    PDF: View PDF  (150 B)

    Description

    Nichol’s Turk’s Head Cactus (Echinocactus horizonthalonius var. nicholii L. Benson; Cactaceae) occurs in a few isolated populations in the Sonoran desert of southcentral Arizona (Pima and Pinal counties). The populations of this variety are disjunct from the more widespread variety that occurs in the Chihuahuan desert of Texas and Mexico. This species occurs only on limestone-derived soils, and the nicholii variety was federally listed as endangered in 1979. Since 1995 we have monitored study plots of this cactus in the Waterman Mountains (AZ), measuring growth and reproduction of about 175 tagged individuals. Growth rates were slow, averaging 0.3 cm in height and 0.2 cm in width per year. Plants usually began flowering when they reached around 4 cm high and 8 cm wide. Of the 52 deaths recorded since 1995, about half followed a visible decline in condition; the rest were unanticipated. There was a distinct jump in mortality during the past two years, possibly due to drought.

    Publication Notes

    • You may send email to rmrspubrequest@fs.fed.us to request a hard copy of this publication.
    • (Please specify exactly which publication you are requesting and your mailing address.)
    • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

    Citation

    McIntosh, M. E.; McDade, L. A.; Boyd, A. E.; Jenkins, P. D. 2007. Patterns of growth and mortality in the endangered Nichol''s Turk''s Head Cactus (Echinocactus horizonthalonius var. nicholii L. Benson; Cactaceae) in Southeastern Arizona. In: Barlow-Irick, P.; Anderson, J.; McDonald, C., tech eds. Southwestern rare and endangered plants: Proceedings of the Fourth Conference; March 22-26, 2004; Las Cruces, New Mexico. Proceedings. RMRS-P-48CD. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 77-82

    Keywords

    plant conservation, Nichol's Turk's Head Cactus, Echinocactus horizonthalonius var. nicholii

    Related Search


    XML: View XML
Show More
Show Fewer
Jump to Top of Page
https://www.fs.usda.gov/treesearch/pubs/29591