He is currently a professor within the Department of Biological Science at Florida State University (FSU), and has been director of FSU's Robert K. Godfrey Herbarium since August 2003.
[1] One of his main areas of research is the phylogenetics of Grevilleoideae, a subfamily of Proteaceae.
In 2005 he showed the genus Banksia to be paraphyletic with respect to Dryandra,[2] Collaborating with Australian botanist Kevin Thiele, he subsequently transferred all Dryandra taxa to Banksia, publishing over 120 taxonomic names in the process.
[3] The change has been adopted by the Western Australian Herbarium,[4] although has met with some controversy.
[5] He has previously worked on the Deep South Plant Specimen Imaging Project, which created a repository of annotated high-resolution digital images of plant specimens within the East Gulf Coastal Plain, a region with a very high diversity of rare and endangered plants.