> The taxonomy and biogeography of British lichens, focussing especially on chemical traits (secondary metabolites).
> Using thin layer chromatography, my research has a focus on difficult genera and I am currently examining phenotypic differences in British Usnea.
> I am also interested in montane saxicolous lichens.
HARROLD, P., Walkinshaw, S., Coppins, B.J. & Ellis, C.J. (2010) Species discrimination and the distribution of Placopsis gelida and P. lambii in Great Britain. British Lichen Society Bulletin, 107: 44-50.
Kelly, L.J., Hollingsworth, P.M., Coppins, B.J., Ellis, C.J., HARROLD, P., Tosh, J. & Yahr, R. (2011) DNA barcoding of lichenized fungi demonstrates high identification success in a floristic context. New Phytologist, 191: 288-300.
HARROLD, P., Grundy, K., Coppins, B.J. & Ellis, C.J. (2009) Distribution of chemotypes of Cetrelia olivetorum in England, Scotland and Wales. British Lichen Society Bulletin, 105: 3-9.
HARROLD, P. (1978) A glabrous variety of Sagina subulata (Sw.) C. Presl in Britain. Transactions of the Botanical Society of Scotland, 43: 1-5.
