Scotch thistle is a native to Europe and Asia that has become a spreading invasive species in Arizona, particularly near disturbed areas — where the ground cover is destroyed or removed, leaving ...

In the northern region of the Sonoran Desert, surrounded by five mountain ranges and 350 days of sunshine, lies Tucson where native edible plants grow. The saguaro, barrel and nopal cacti are ...

Wildfires can burn and spread differently depending on what vegetation they burn. The two fires in northern Arizona have ...

A Tucson-based environmental group is petitioning the U.S. Fish and Wildlife Services to put seven amphibians and reptiles on the endangered species list, including four native to Arizona.

A 2022 assessment of tree species native to the contiguous U.S. found 11-16% of species are threatened with extinction. The greatest threats are invasive pests and diseases.