A green-thumbed detective

Anita Cholewa is a curator at the University of Minnesota’s Bell Museum, and a self-professed expert in plant trivia. But when it comes to forensic investigation, her knowledge of plants becomes much more than trivia. Cholewa can identify a plant based on the microscopic features of a flower petal, or from the details on fragment of a leaf. If a particular plant is found at a crime scene and associated with a suspect, it might be used as evidence to show that that suspect was at the scene.

Plants can also reveal information about the time a crime was committed. Pollen from a crime scene can indicate the time of year the incident occurred, or a half-grown plant covered by a body might indicate how long the body has lain in that spot. The yearly growth patterns in rings of wood can even be used to help date older crime scenes.

Sometimes forensic botanists must identify plant evidence based on tiny scraps of material. Only a taxonomic expert might connect this fragment of petal to its source…

Photo courtesy Ah Pao via flickr.com

…a spiderwort flower. If this plant were found at a crime scene and traces of it were discovered on a suspect, it could prove to be a valuable piece of an investigation.

Photo courtesy bunchofpants via flickr.com