Thomas Hawkes Nash III

During his long career at the Arizona State University, he helped develop the lichen herbarium into a world-class collection with over 100,000 specimens representing more than 5000 species.

[2] His Ph.D. thesis, titled Effect of Effluents from a Zinc Factory on Lichens,[1] was later published in the journal Ecological Monographs.

[3] Shortly after graduation, he accepted an assistant professorship from Arizona State University in Tempe, where he has spent much of his scientific career.

[2] Nash curated and edited the exsiccata series Lichenes exsiccati, distributed by Arizona State University.

[7] His research is largely focused on the biology of lichens and the effects of air pollution on plants.

[8] He developed an interest in lichen physiology after working for a while with Otto Ludwig Lange at the University of Würzburg.

Nash's interest in taxonomy developed with his work on the flora of the southwestern United States, and he is considered a leading expert in the family Parmeliaceae, particularly the genera Hypotrachyna and Xanthoparmelia.

[1][9] The latter project, funded by the National Science Foundation, was a large collaborative work involving more than 90 scientists from 23 countries.

[6][8] Taking almost 18 years to complete, much of the effort was taken up through numerous field trips to hundreds of localities throughout the region.

[2] In 2008, Nash was the chair of the organizing committee for the sixth International Lichenological Symposium, which was held at the Asilomar Conference Grounds in Monterey, California.

[6][10] As of 2011, Nash had mentored 30 graduate students (19 Ph.D. and 11 Masters), and authored or co-authored more than 200 peer-reviewed scientific publications.