Charles Lester Boyd’s “A Flora of the Sligo Valley in Montgomery and Prince George [sic] Counties, Maryland” was completed in 1940 as his master’s dissertation at Catholic University. His work was supervised by Hugh O’Neill and J. P. Parker, two leading botanists of the era. Boyd personally observed most of the plants he listed during field work in 1938 and 1939. These he supplemented with historical specimens collected in the Sligo watershed, and just beyond, by earlier botanists and deposited in herbaria at the Smithsonian, Catholic University, and the University of Maryland. These specimens date as far back as the 1870s. Boyd’s Flora includes native plants as well as garden species that had escaped cultivation and occurred in Sligo parklands. He occasionally mentions street trees. Unique among the floras of Sligo, Boyd’s also covers fungi; he personally identified more than 100 species in Sligo.
In his introduction, Boyd explains the borders he used to define the Sligo watershed, which are a bit broader than those in use today, especially along the southern reaches. Boyd’s own topographic map of the watershed is included in his introductory material, allowing the reader to locate most of the sites he mentions in the text.
The entire dissertation is provided here in eight folders averaging about ten pages each. Three indexes list the plant families in alphabetical order by scientific (Latin) name and by common name, using the terms as they appear in Boyd’s original. Some names have changed since his time, such as the Pea (or Bean) Family, which he calls Pulse, and the family Cruciferaceae (Mustards), which he calls Brassicaceae. A third index lists the families in numerical order by page number. In all three indexes, page numbers are hot-linked to the relevant folder. In some instances, a plant family is spread across two folders.
Plant species marked with an asterisk indicate those for which Boyd found herbarium specimens from Sligo (or very nearby) in the Smithsonian’s herbarium. Those from two other herbaria are noted in the text. A bound, hard copy of the Flora can be found in the reference section at the Takoma Park, Maryland, Library and at Catholic University.
Many thanks to our webmaster, Clair Garman, for his resourceful, persistent, and rapid work in making this invaluable resource so readily available on our website.
Michael Wilpers, Natural History Committee