he joined The Morton Arboretum in Lisle, Illinois as the director of education, teaching botany and natural history. He became the arboretum’s plant taxonomist in 1963. He continued to work for the Morton Arboretum for almost 40 years. Few and out-of-date botanical resources were available to Chicago area botanists in the 1960s. At the request of Northern Illinois University's Dr. Herbert Lamp, in 1965 Swink typed up a list of plants from M. L. Fernald's 8th edition of Gray's Manual that included only those species found in the Chicago area. It became known by naturalists as the "Lamp List." After several years fervently collecting plant specimens and county records throughout the region, Swink published Plants of the Chicago Region in 1969. Only 250 copies were printed and it quickly sold out. This regional flora compiled wild plant occurrences from counties in northeastern Illinois, southeastern Wisconsin, northern Indiana, and southwestern Michigan—an area delimited by what was considered a reasonable a day trip from Chicago. In contrast with other floras which were sometimes deemed "too recondite for the weekend botanist," the plants were sorted alphabetically by genus rather than in phylogenetic order and author citations were excluded, to the disapproval of some other contemporary botanists. Plants of the Chicago Region was also distinctive in providing lists of "associated" plant species for each entry, and with later editions rendering non-native species in italics while leaving native species non-italicized. These unique features of the flora reflected the nascent community of ecological restoration practitioners that grew out of the Chicago region in the mid-20th century. The lists of associate species have been widely referenced by regional restoration projects, including Stephen Packard's efforts to restore savannas along the North Branch of the Chicago River. Swink continued work on this regional flora for several decades. The second edition was published in 1974. The third edition, co-authored with Gerould Wilhelm, was published in 1979, and the fourth and final edition was published in 1994. The third edition of Plants of the Chicago Region was the first regional flora to include coefficients of conservatism for each plant species, following the Floristic Quality Assessment system originally conceived by Wilhelm in 1977 for Kane County, Illinois. Accolades Swink was awarded an honorary doctorate in 1995 by Western Illinois University for the vast botanical and ornithological knowledge he had acquired by individual study, as well as his generosity in sharing that knowledge