Fringed Twinevines (Funastrum cynanchoides) are very common in the Sonoran Desert areas around Tucson. These poisonous vines are members of the Milkweed Family (Asclepiadaceae) and have white to purple flowers with fringed petals and narrowly linear to heart-shaped leaves.

These vines either sprawl on the ground or twine through other plants, so when I saw this Fringed Twinevine "bush", I knew that there must be something else hidden beneath it.

The above Fringed Twinevines were so dense that it was difficult to see what they were smothering, but then I saw the characteristic red fruits of an unfortunate Cactus Apple or Engelmann's Prickly Pear (Opuntia engelmannii) cactus.

These cacti are sun-loving, so several months of complete shade under the Fringed Twinevine may be harmful to the poor cactus.