Vascular Plant and Vertebrate Inventory of Saguaro ... - USGS

Figure 2.1. Location of the two districts of Saguaro National Park in southern Arizona.
Average annual temperatures for low
elevations from 2001 to 2003 were above the
long-term mean of 21.3 o C (21.5 o C in 2001,
21.6 o C in 2002 and 22.0 o C in 2003; Fig 2.3;
WRCC 2005). Average annual temperatures for
high elevations ranged from slightly below to
slightly above the long-term mean of 8.5 o C (6. o C
in 2001, .3 o C in 2002 and 9.5 o C in 2003; Fig
2.3; PCFCD 2005), though these records have
only been kept for 10 years.
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Vegetation and Biotic Communities
The Rincon Mountain District encompasses
most of the Rincon Mountains, one of the “sky
island” mountain ranges of southeast Arizona
and northern Mexico. Sky islands, so called
because the “sky” mountains are isolated by
“seas” of desert and semi-desert grasslands, are
areas of remarkable biological diversity as a
result of elevational gradients and subsequent