BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Ferocactus wislizenii | Barrel Cactus 



GENERAL BOTANICAL CHARACTERISTICS : 
Barrel cactus is a native stem succulent that is barrel-shaped or
sometimes columnar with rarely more than one stem.  It ranges from 2
to 10 feet (3 m) tall, with a diameter of 18 to 33 inches (45-83 cm).
Barrel cactus has 20 to 28 ribs.  The spines are dense, somewhat
obscuring the surface of the stem.  There are four central spines per
areole, the larger ones 1.5 to 2 inches (3.8-5.0 cm) long, and 12 to 20
radial spines to 1.8 inches (4.5 cm) in length.  Flowers form on growth
of the current season near the stem apex.  The fruit is yellow,
barrel-shaped, and fleshy at maturity [1,17,36].

According to Cannon [7], the root system of barrel cactus is shallow and
confined to the upper soil layers.  At one site a main anchoring root
extended down to about 8 inches (20 cm) and had several short laterals.
Horizontal roots originated from the root crown and were very shallow.
Depth of burial decreased with distance from the plant and ranged from
0.6 to 1.2 inches (1.5-3.0 cm).  Roots were often exposed after rain
storms.


RAUNKIAER LIFE FORM : 
   Stem succulent


REGENERATION PROCESSES : 
Glendening [10] stated that barrel cactus reproduces from seeds only,
which are dispersed by birds and rodents [10,38].  No offsets were
reported after fires in southern Arizona; growth was from the apical
meristem only [31].  Ferocactus species will often branch at the apex
following injury to the terminal bud [1].

Limiting factors for germination of barrel cactus seeds are temperature
and light.  Greatest germination takes place at 68 to 86 degrees
Fahrenheit (20-30 deg C) after at least 8 hours of light.  Seeds do not
germinate in the dark [12].


SITE CHARACTERISTICS : 
Barrel cactus is found on rocky, gravelly, or sandy soils of hills,
flats, canyons, wash margins, and alluvial fans in desert shrublands and
grasslands from 990 to 5,280 feet (300-1,600 m) elevation [1,35,38].  It
also extends into woodland communities occurring at elevations below
6,500 feet (1,970 m) [14].  Barrel cactus is frost-sensitive [28], which
is a limiting site factor at higher elevations and northern latitudes.


SUCCESSIONAL STATUS : 
Barrel cactus' life span has been reported to be from 50 [11] to 130
years [26].  It is a climax member of the desert grassland [27].


SEASONAL DEVELOPMENT : 
Barrel cactus flowers sporadically in late spring and profusely in the
summer (July to September) [1,17].

Related categories for Species: Ferocactus wislizenii | Barrel Cactus