Dr. Billy A Krimmel 
PERT Postdoctoral Fellow, 
Department of Entomology, University of Arizona 

Dr. Billy Krimmel studies how plants maximize their fitness using resistance techniques by focusing on a common California weed. The tarweed is native to California; it historically played a part in the survival of indigenous people, as the seeds were used by the Pomo Indians as a source of food. Today, hikers know it as an annoying plant that sticks to their pants and socks. The tarweed is part of a group of species known as “Sticky Plants.” As Dr. Krimmel explains, the tarweed is covered with hairs, which have microscopic bubbles at their ends. When something, such as a predatory insect, touches the bubble, it pops and a sticky liquid is excreted, along with a strong odor. This makes the plant surface inaccessible, and dead insects sometimes can be seen stuck to the surface of tarweeds. 

Recorded: February 27, 2015