The Case of the Seedy Blanket

There was no witness to the crime, except for the blue plaid blanket fibers found recovered on the ceremonial figure. It had been dragged into the marshy area behind the museum.

After four days, police finally identified a likely suspect. In the trunk of her car was a blue plaid blanket---damp and covered in crushed leaves and other plant material.

Detective Wright arrested the suspect and immediately called a forensic botanist to examine the evidence.

“Interesting,” said Dr. Green, “it is unusual to see beard grass, dog fennel, and beak rush growing together.”

Pointing to the leaves and seeds embedded in the blanket, he continued, “Look, a few seeds are starting to germinate.” He took the blanket to the lab for further investigation and collected plant samples from the crime scene and around town.

Called to the witness stand to provide expert testimony, Dr. Green cleared his throat and immediately began confidently outlining evidence that countered the suspect’s claim.

At the trial, the suspect claimed that although she visited the museum, she had never been outside except in the museum’s parking lot. She had used the blanket during a picnic at the city park on the day before her arrest.

What do you think this case is about?

What do you already know that relates to this case?

What do you need to know to understand the case?

How might this case be used to teach?

What sorts of plant information do you think Dr. Green presented to the jurors that indicated:

• Where the suspect had been? • When?

Evidence Description ConclusionMap of crime sceneImages of vegetation

Map of parkImages of vegetation

Plant specimens

Seed identifications

Germination data: Temperature experiments

Germination data: time sequence

Table of Potential Evidence

References for The Case of the Seedy Blanket

and Botanical Forensics

NATIONAL WILDLIFE MAGAZINE Feb/March 1992, vol. 30 no. 2 When Scientists Become Sleuths by Richard and Joyce Wolkomi http://www.nwf.org/nationalwildlife/index.cfm?issueID=87

Graham, S. 2006. Crime-solving plants. Plant Science Bulletin 52(3). http://www.botany.org/plantsciencebulletin/PSB52-3.pdf

Incorporating Online Resources:Digital Image Collections, Distribution

Maps

University of Florida Herbarium, Digital Imaging http://www.flmnh.ufl.edu/herbarium/cat/digitalimagingprojects.htm

Florida Flora Picture Gallery, Bushy Beardgrass habitathttp://www.virtualherbarium.org/lf/glomer.jpg

USDA Plants Database records on Dog Fennel, Bushy Beardgrass, and Beak Rush

http://plants.usda.gov/java/profile?symbol=EUCA5http://plants.usda.gov/java/profile?symbol=ANGL2http://plants.usda.gov/java/profile?symbol=RHME3