American surgeon and botanist. John Milton Bigelow came from a poor family that moved from Vermont to Ohio in 1815, but as a young man managed to earn enough money from schoolteaching to attend medical school in Cincinnati and establish a successful country practice in Lancaster, Ohio. An amateur botanist, in 1841 he published Florula Lancastriensis, a catalogue of the plants of Fairfield County which included medical notations on almost 200 plants.

In 1850, at the age of 46, he accepted the position of surgeon on the Mexican Boundary Survey led by Lieutenant A.W. Whipple. Seeing the commission as an opportunity for botanical exploration, the leading American botanists of the period, John Torrey and Asa Gray, had gained permission to attach botanists to the field party, which would be crossing previously unexplored territory. Bigelow was recommended to Torrey by the bryologist William S. Sullivant from Columbus, Ohio, whom he had known since about 1840. Three other collectors were attached to the survey, C.C. Parry, George Thurber, and Charles Wright, the latter a lifelong friend of Gray who had previously collected in Texas. The bulk of collecting was done by Parry and Bigelow. The botanists did not always travel together; in the beginning Thurber followed the northern route, Bigelow the southern, and eventually they were met by Parry and Wright. Some of Bigelow's collections were made on an excursion to Lake Guzman in northern Chihuahua. Perhaps his most important discovery on this journey was Parthenium argentatum, a rubber-yielding plant commonly known by its Mexican name 'guayule'.

Not long after the party was disbanded, Lt Whipple was commissioned to survey a route for a railroad between the 35th and 36th parallels, and he asked Bigelow to join the expedition as surgeon and botanist. The field party for the Pacific Railroad Expedition followed a line from Fort Smith, Arkansas, to the Mojave Desert in southwestern California and finally to Los Angeles. Although by far the oldest member of the expedition, Bigelow was a general favourite, and was described in the diary of the expedition artist, Baldwin Mollhausen, as "a pattern of gentleness and patience always…never wanting when a hearty laugh or good joke was to be heard….To his patients he was kind and attentive, and of his mule Billy he made an absolute spoiled child." Leaving the party in San Diego at the end of the expedition, Bigelow continued on his own to northern California, and was one of the first botanists to see living stands of Sequoiadendron giganteum.

Torrey wrote to Gray that Bigelow's collections were in "perfect order. A number of new genera and more than sixty new species have been discovered by Dr Bigelow and he has added much valuable information upon many heretofore imperfectly known plants." In July 1854 Bigelow met with other members of the expedition in Washington, D.C., to prepare their reports. Bigelow divided his into five parts: a general account of the topography and climate of the territory; notes on trees and their potential for supplying timbers for railroad ties; a list and description of his extensive collection of cacti, made in collaboration with George Engelmann of St Louis; Torrey's description of the ferns and flowering plants; and, finally, Sullivant's description of mosses from California. After resuming his medical practice in Ohio for some years, Bigelow moved to Detroit, Michigan, in 1860 or 1861 to work on the Great Lakes Survey as a meteorologist and a little later became professor of botany and pharmacy at Detroit Medical College. In 1868 he was appointed surgeon to the Marine Hospital. In a short discursive memoir, "The Medical Botany, Topography and Climate, of the Southwestern States and Territories," published in volumes two and three of the Detroit Review of Medicine, he discussed the families of plants encountered on his explorations. There is a long list of eponyms, with the epithet bigelovii, which contains seventeen species from California alone including Corallorhiza bigelovii S. Watson (= Neottia bigelovii (S. Watson) Kuntze), Mimulus bigelovii A. Gray, Opuntia bigelovii Engelm. (= Cylindropuntia bigelovii (Engelm.) F.M. Knuth) and Scoliopus bigelovii Torr.

Sources:
L. Blakely, 2000, "Who's in a Name?", California Native Plant Society (Bristlecone Chapter) Newsletter, 20(4): 2
J.A. Ewan, 1981, Biographical dictionary of Rocky Mountain naturalists: 19
A.E. Waller, 1942, "Dr John Milton Bigelow, 1804-1878: An Early Ohio Physician-botanist", Ohio History, 51: 313-331.