A number of invasive perennial and annual exotic grasses are identified as serious threats to native Sonoran Desert biota, where Saguaro National Park (SNP) is located.  The Arizona Upland subdivision of the Sonoran Desert, characterized by the giant saguaro and foothill palo verde, is particularly at risk because these dominant plant species experience high mortality from fire. 

Project Details

Invasive exotic grasses provide a more continuous combustible fuel bad, which can increase fire size and frequency in the Sonoran Desert.  Recurrent fires threaten fire-intolerant desert plant species, especially the saguaro, to the point of localized extinction, and could result in vegetative type conversions from desert scrub to fire-adapted grasslands.  SNP has seen an increase in human-caused wildfires since the 1960s, threatening the Park's protected Sonoran desert vegetation, and potentially creating a more favorable environment for exotic fire-adapted species.

 

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