• GENERAL BOTANICAL CHARACTERISTICS
• RAUNKIAER LIFE FORM
• REGENERATION PROCESSES
• SITE CHARACTERISTICS
• SUCCESSIONAL STATUS
• SEASONAL DEVELOPMENT

GENERAL BOTANICAL CHARACTERISTICS:

Big galleta is a native perennial grass. It is highly branched at the base, giving it a bush-like appearance. The coarse, rigid culms are erect or decumbent and reach 12 to 40 inches (30-100 cm) in height [11,20,21,27]. Big galleta's clumped growth form is a result of the tillers [36,37] or short rhizomes it produces [11,37,46].

Big galleta is reported to be more effective than many other desert plants at extracting water from the soil during dry periods [15,16,18]. Its root system tends to be shallow and extends radially from the base of the plant. Mean root depths of big galleta plants at sites in the Sonoran Desert ranged from 3 to 4 inches (8-10 cm) [10,15,37].

RAUNKIAER LIFE FORM:

Hemicryptophyte
Geophyte

REGENERATION PROCESSES:

Big galleta primarily reproduces by rhizomes [42], and most likely by tillering as well.

Little information is available on germination characteristics of big galleta. Seed production is generally very poor [19] and seedling establishment appears to be rare [41].

SITE CHARACTERISTICS:

Big galleta is found on dry, open, sandy to rocky slopes and flats, on sand dunes, and in bajadas, scrublands, woodlands, and desert areas [20,21,27,46]. Big galleta occurs on all soil textures, but displays poor growth on clays [12].

Big galleta is reported to be the most drought tolerant of the Pleuraphis species and is well adapted to desertscrub communities [19]. It is widely distributed on sand dunes throughout the lower Colorado River Valley of the Sonoran Desert and in some Mohave Desert communities [50,51]. In Arizona, big galleta reaches best development in depressions and on heavy alluvial soils below 4,000 feet (1200 m) [27]. Big galleta is generally found below 4,800 feet (1600 m) in California [20] and below 3,600 feet (1220 m) in Utah [54].

SUCCESSIONAL STATUS:

Big galleta colonizes sand dunes and disturbed sandy areas throughout the Sonoran and Mohave deserts [9,32,36,51].

An apparent symbiotic relationship exists between big galleta and cholla cacti (Opuntia spp.) in the Mohave Desert. Big galleta acts as a nurse plant to cholla seedlings while juvenile cholla offer big galleta protection from herbivores. However, cholla plants larger than 27.5 inches (70 cm) eventually shade big galleta out [10]. Big galleta also apparently acts as a nurse plant to California barrel cactus (Ferocactus cylindraceus) and desert agave (Agave deserti) on Sonoran Desert sites [15,16].

Big galleta was not found on young (5-year-old) debris flow terraces in the Grand Canyon, but was present on 28-year-old and 240-year-old sites [4].

SEASONAL DEVELOPMENT:

Big galleta generally undergoes 2 major growth periods, coinciding with the typical bimodal rainfall patterns within its area of distribution [41]. It also can complete its life cycle rapidly in response to periodic rains. In 1 California study following an August 11th rainfall, big galleta flowered by August 30th and dispersed seed by September 15th [36]. Big galleta typically flowers from February through June in the Mohave Desert [49], and from February through September in Arizona [27].

Related categories for SPECIES: Pleuraphis rigida | Big Galleta