1. Milkweed of southwestern United States and Mexico; poisonous to livestock
   - poison milkweed, horsetail milkweed

Type of: milkweed, silkweed

• ursine dasyure
• ursinia
• Ursuline
• Ursus
• Ursus americanus
• Ursus arctos
• Ursus arctos horribilis
• Ursus arctos middendorffi
• Ursus arctos syriacus
• Ursus horribilis
• Ursus Maritimus
• Ursus middendorffi
• Ursus thibetanus
• Ursus ursinus
• Urth
• Urtica
• Urtica dioica
• Urtica pipulifera
• Urticaceae
• Urticales
• urticaria
• urticate
• urtication
• Urubupunga
• Urubupunga Falls