Saguaro (Carnegiea Gigantea) Densities and Reproduction Over the Northern Sonoran Desert

  title={Saguaro (Carnegiea Gigantea) Densities and Reproduction Over the Northern Sonoran Desert},
  author={Taly Dawn Drezner},
  journal={Physical Geography},
  pages={505 - 518}
  • T. Drezner
  • Published 1 January 2006
  • Environmental Science
  • Physical Geography
Casual observations suggest that saguaro populations are densest in southeastern Arizona, although data have not been collected and no study has been done to address this topic. In addition, the topic of reproductive density has similarly never been addressed. Saguaro reproductive output is directly related to the number of adult individuals and the number of branches in the area. Thirty saguaro populations over their U.S. range were sampled to consider two variables: population density and… 
Episodic recruitment in the saguaro cactus is driven by multidecadal periodicities.
It is found that saguaros rely on multidecadal periodic pulses of good beneficial years to incorporate new individuals into their populations with periodicities of 20-30 years possibly related to strong El Niño Southern Oscillation events.
The keystone saguaro (Carnegiea gigantea, Cactaceae): a review of its ecology, associations, reproduction, limits, and demographics
This paper reviews the basics of a Sonoran Desert keystone cactus species, including the ecology of its establishment and high mortality, its association with nurse plants to provide ameliorated
Variability in reproductive effort of a keystone species: age and height of branch establishment
Of greatest concern is the advanced age at which branching begins at the most marginal, arid site, which is around the same time that old-age mortality may set in for the species (generally), dramatically diminishing reproductive output in an already marginal population.
Variations In Saguaro Cactus (Carnegiea gigantea) Spine Length In Wet and Dry Portions of Their Range
Spine length in the keystone Carnegiea gigantea (Engelm.) Britton & Rose in two northern Sonoran Desert populations where this species is ultimately limited by cold temperatures increases, providing thermal protection and reducing photosynthesis, where temperature is more extreme and where conditions are more xeric.
Variation in age and height of onset of reproduction in the saguaro cactus (Carnegiea gigantea) in the Sonoran Desert
Statistical results are robust and significant variations in the onset of reproduction are observed by both age and height across the four sites, which have implications for regeneration, particularly in marginal locales where regeneration is already limited.
Regional Branching Relationships in Carnegiea gigantea, A Keystone Cactus
A significant relationship in peaks and troughs is detected between the 2 very different populations, suggesting a regional influence over branching that extends beyond a population or local area.
Nonlinear modeling of saguaro growth rates reveals the importance of temperature for size-dependent growth.
The most parsimonious model was the Ricker function that described growth considering cactus decline with age, and Variance in temperature, rather than precipitation, was more closely related to growth.


Regeneration of Carnegiea gigantea (Cactaceae) since 1850 in three populations in the northern Sonoran Desert
Saguaro Distribution under Nurse Plants in Arizona's Sonoran Desert: Directional and Microclimate Influences*
Abstract The saguaro cactus, an icon of the American southwestern desert, defines the extent of the Sonoran Desert through portions of its range. Saguaros rely upon nurse plants for establishment and
A test of the relationship between seasonal rainfall and saguaro cacti branching patterns
Reproductive output, as well as photosynthetically active radiation interception and CO 2 uptake, increase as saguaro cacti Carnegiea gigantea (Engelm.) Britt. and Rose branch, and branching
Saguaro (Carnegiea gigantea, Cactaceae) age-height relationships and growth: the development of a general growth curve.
  • T. Drezner
  • Environmental Science
    American journal of botany
  • 2003
With this formula and relatively little field sampling, the age of any individual saguaro (whether the individual was sampled or not) in any population can be estimated.
Association between cacti and nurse perennials in a heterogeneous tropical dry forest in northwestern Mexico
. The Sierra de La Laguna, Baja California Sur harbors the only tropical dry forest of the Peninsula. An inventory of the perennial plants was carried out at the eastern part of this mountain range.
Sahuaro-nurse tree associations in the Sonoran Desert: competitive effects of sahuaros
It is shown that the close proximity of sahuaros leads to a relative increase in stem die-back as well as greater mortality in a common nurse tree, the foothill paloverde (Cercidium microphyllum).
Morphology, Nurse Plants, and Minimum Apical Temperatures for Young Carnegiea gigantea
If the northern limit of C gigantea reflects wintertime survival of juveniles, nurse plants could extend the range by offering some protection against freezing by extending the range of apical temperatures.
The importance of Olneya tesota as a nurse plant in the Sonoran Desert
Olneya tesota must be considered as a habitat modifier species with ecological and conservational importance to the plant communities in the Sonoran Desert.
Morphology, Surface Temperatures, and Northern Limits of Columnar Cacti in the Sonoran Desert
Interspecific morphological differences and intraspecific morphological changes with latitude were evaluated to help examine the distributional ranges of Carnegiea gigantea, Lemaireocereus thurberi,