A colorful willow leaf collected along on of the Pumice Plain streams at Mount St. Helens. Photo by Carri LeRoy 

Across the Pumice plain of Mount St. Helens, our research has focused mainly on understanding how plant sex differences influence ecosystem processes. Members of our lab are studying the leaf litter of male and female willows at a chemical level!

Evergreen undergraduate Iris Garthwaite standing in front of the TOF mass spectrometer at the Center for Urban Waters in Tacoma.  Photo by Joy Ramstack Hobbs 

To identify if male and female willows have unique chemical signatures, we measured condensed tannin, C and N, and a whole suite of compounds using Time of Flight Mass Spectrometry (TOFMS) in collaboration with the Center for Urban Waters at UW Tacoma. 

TOF Mass Spec readings give preliminary identification of the compounds in the willow samples. Of the 1,500 -1,600 individual compounds isolated in each sample, there were about 150 compounds that differentiate between the male and female willow samples at MSH! 

Cluster diagram showing over 100 compounds that vary between male and female willows (red = present, blue = absent). Unpublished data.