Subspecies, varieties, forms and cultivars of plants belonging to the Opuntia polyacantha group

• Opuntia polyacantha Haw.: (var. polyacantha) has spines rarely exceeding 5 cm (2 in) in length, and dense spines on the fruits. Distribution: Alberta and Saskatchewan south to western Texas, New Mexico, and southeastern Utah.
• Opuntia polyacantha var. albispina (Engelm. & J.M.Bigelow) J.M.Coult.: is a creeping form with spines to only 3.5 cm long, and some spines on the fruits. Distribution: New Mexico, west Texas, and Mexico.
• Opuntia polyacantha var. arenaria (Engelm.) B.D.Parfitt: is a creeping form with spines to only 3.5 cm long, and some spines on the fruits. Distribution: southeastern New Mexico, west Texas, and neighboring Mexico.
• Opuntia polyacantha var. erinacea (Engelm. & J.M.Bigelow) B.D.Parfitt: has spines to 10 cm long, and very spiny fruits. Distribution: western United States.
• Opuntia polyacantha var. hystricina (Engelm. & J.M.Bigelow) B.D.Parfitt: has spines to 10 cm long, and fruits that are spiny above. Distribution: from northern Arizona to Colorado.
• Opuntia polyacantha var. nicholii (L.D.Benson) B.D.Parfitt: has spines to 12.5 cm long, and some spines on the fruits. Disstribution: Navajoan
  Desert of Utah and Arizona.
• Opuntia polyacantha var. platycarpa (Engelm.) J.M.Coult.
• Opuntia polyacantha var. schweriniana (K.Schum.) Backeb.