Last summer, I stood in my garden with a can of pesticide, ready to wipe out every crawling thing in sight. Then I hesitated, because...

Last summer, I stood in my garden with a can of pesticide, ready to wipe out every crawling thing in sight. Then I hesitated, because...

Phenomenon Introduction Have you noticed the mysterious yellow patterns on rose leaves along your school’s tree-lined paths? These lightning-like markings are symptoms of a “plant...