The approximate limits of the Chihuahuan Desert Ecoregion, where it occurs in the United States. It is based on:
1) continental / oceanic influences
2) aridity, late summer precip season / cool season to spring drought
3) temperature, coldest monthly mean >32F, growing season >175 days, at least 50 days >90F
4) desert grassland and desert scrub, indicator plants where the core of their range are in the Chihuahuan Desert include:
- Chilopsis linearis
- Prosopis torreyana
- Prosopis pubescens
- Yucca elata
- Yucca torreyi
- Aloysia wrightii
- Flourensia cernua
- Larrea tridentata (diploid only)
- Parthenium incanum
- Psorothamnus scoparius
- Rhus microphylla
- Agave lechuguilla
- Dasylirion leiophyllum
- Dasylirion wheeleri
- Echinocereus dasyacanthus var. dasyacanthus
- Echinocereus stramineus
- Ferocactus wislizeni
- Opuntia macrocentra
- Bouteloua eriopoda
- Muhlenbergia porteri
- Sporobulus wrightii