Sacahuista—_See_ Beargrass
Saguaro—_Carnegiea gigantea_
Scorpionweed—_Phacelia crenulata_
Screwleaf muhly—_Muhlenbergia virescens_
Shindagger—_See_ Amole
Shrub live oak—_Quercus turbinella_
Sideoats grama—_Bouteloua curtipendula_
Silktassel—_Garrya wrightii_
Silverleaf oak—_Quercus hypoleucoides_
Skunkbush—_Rhus trilobata_
Snakeweed—_Futierrezia sp._
Snowberry—_Symphoricarpos oreophilus_
Sotol—_Dasylirion wheeleri_
Spanish dagger—_Yucca schottii_
Sprucetop grama—_Bouteloua chondrosioides_
Staghorn cholla—_Opuntia versicolor_
Tanglehead—_Heteropogon contortus_
Teddy bear cholla—_Opuntia bigelovii_
Texas bluestem—_Andropogon cirratus_
Triangle bursage—_Franseria deltoidea_
Turpentine-bush—_Haplopappus laricifolius_