Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Taxonomy and Distribution of a Natural Group of Black Oaks of Mexico (Quercus, Section Lobatae, Subsection Racemiflorae)

Richard Spellenberg and Jeffrey R. Bacon
Systematic Botany
Vol. 21, No. 1 (Jan. - Mar., 1996), pp. 85-99
DOI: 10.2307/2419565
Stable URL: http://www.jstor.org/stable/2419565
Page Count: 15
  • Read Online (Free)
  • Download ($12.00)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Taxonomy and Distribution of a Natural Group of Black Oaks of Mexico (Quercus, Section Lobatae, Subsection Racemiflorae)
Preview not available

Abstract

A taxonomy of a small section of Mexican black oaks (Quercus, section Lobatae, subsection Racemiflorae) is presented. Four species are recognized; Q. conzattii, Q. radiata, Q. tarahumara, Q. urbanii. All are annual-fruited, the acorns in racemose inflorescences ranging from condensed or reduced to elongate, the species differing by characteristics of inflorescences and foliar pubescence. Quercus urbanii and Q. conzattii are bicentric, each occurring in the southern part of the Sierra Madre Occidental and again several hundred kilometers to the south. Both have leaves densely lanate and moderately glandular on the abaxial surface; Q. urbanii has robust inflorescences 4-17 cm long whereas Q. conzattii has more delicate inflorescences 0.5-6 cm long. Quercus tarahumara and Q. radiata are restricted to the northern and southern parts of the Sierra Madre, respectively. Both have leaves conspicuously glandular and sparsely lanate on the abaxial surface; inflorescences are rather robust, those in Q. radiata openly racemose and 5-19 cm long, those of Q. tarahumara dense, compact, and 0.5-4 cm long.

Page Thumbnails

  • Thumbnail: Page 
85
    85
  • Thumbnail: Page 
86
    86
  • Thumbnail: Page 
87
    87
  • Thumbnail: Page 
88
    88
  • Thumbnail: Page 
89
    89
  • Thumbnail: Page 
90
    90
  • Thumbnail: Page 
91
    91
  • Thumbnail: Page 
92
    92
  • Thumbnail: Page 
93
    93
  • Thumbnail: Page 
94
    94
  • Thumbnail: Page 
95
    95
  • Thumbnail: Page 
96
    96
  • Thumbnail: Page 
97
    97
  • Thumbnail: Page 
98
    98
  • Thumbnail: Page 
99
    99