Bolton was a self-taught naturalist, achieving expertise in birds, butterflies and "plant"s, and worked as a illustrator for natural history publications. He grew interested in fungi when he was asked to make a list of plants for William Watson's (1775) The history and antiquities of the parish of Halifax, in Yorkshire, uncovering 55 species in the course of his research. In due course, he issued his History, which created his place in mycology. As with the work of Nees von Esenbeck and James Sowerby, the main feature of Bolton's work is the quality of its illustrations, which actually allow one to recognize the fungus from the picture. His book (like Nees') was thus a valuable standard, to which one could refer to make sure that a correspondent was refering to the same mushroom that you were. Bolton's History was translated into German (1795-1820), the first three volumes by Willdenow and the last volume by Nees von Esenbeck and T. Nees von Esenbeck, his son.