We study the genetic networks that enable plants to dynamically sense and respond to environmental signals. My lab is currently investigating a mystery of fire ecology: how is seed germination activated after a fire by chemical signals found in smoke? A potent class of germination-promoting compounds known as karrikins were identified in smoke in 2004. We are using genetic approaches in the model organism Arabidopsis thaliana to define the karrikin signaling mechanism in plants. Along the way we are discovering how strigolactones, a family of plant hormones that use the same signaling pathway, control plant development. We are using our knowledge of karrikin and strigolactone signaling mechanisms in Arabidopsis to determine how parasitic weeds detect their hosts - a key first step toward solving a major agricultural problem.