Question: Which botanist published the most popular botany book of his time?

John Gerard, also spelt John Gerarde, (c. 1545–1612) was a botanist and herbalist.  His chief notability is as the author of a large (1,484 pages) illustrated "Herball, or Generall Historie of Plantes".  He maintained a large herbal garden in London.  First published in 1597, it was the most widely circulated botany book in English in the 17th century.  Except for the additions of a number of plants from his own garden and from North America, Gerard's "Herbal" is largely an unacknowledged English translation of Rembert Dodoens's herbal originally published in 1554, itself also highly popular (in Dutch, Latin, French and other English translations). <SEP> Georg Heinrich Leopold Dippel (4 August 1827 – 4 March 1914) was a German botanist.  He was the son of a royal Bavarian forester, Carl Friedrich Peter Dippel, and Sussanna Purpus.  He attended schools is Kaiserslautern and Zweibrücken.  From 1845, he studied at the Academy of Forestry in Aschaffenburg, until he graduated in 1848.  During his time there he was a member of the Munich Corps Hubertia fraternity.  He continued his studies in Jena under the tutelage of Matthias Jacob Schleiden.  Under him, he learned more extensively about botany and pioneered his work in microscopy and his research on the structure of plant's bodies.  From July 1869, he worked at the Technische Universität Darmstadt, as a Professor of Botany and Zoology, Botany, and Cellular Histology.  His interests turned towards Dendrology at this point.  He brought many foreign trees and shrubs, mostly collected by his first cousin Carl Albert Purpus in North America and Mexico, and sent them to Germany.  He was the rector of the Technical University of Darmstadt from 1870–71 and the Dean of the Chemical-Technical School from 1882-87.  He retired at the end of the summer semester in 1896. <SEP>  It provided unacknowledged material for John Gerard's better-known "Herball" (London, 1597) and was reprinted in Germany throughout the 17th century. Jacobus Theodorus (Jakob Dietrich), called Tabernaemontanus (1525 – August 1590) was a physician and an early botanist and herbalist, the "father of "German botany" whose illustrated "Neuwe Kreuterbuch" (1588) or "Eicones Plantarum" (Frankfurt, 1590) was the result of a lifetime's botanizing and medical practice.  His Latinized name represented a translation of his native town, Bergzabern (literally ‘mountain taverne’) in the Palatinate.  Tabernaemontanus began as a student of the pioneer of Renaissance botany, Hieronymus Bock. <SEP> Charles Frederick Millspaugh (1854–1923) was an American botanist, born at Ithaca, N.Y., and educated at Cornell and the New York Homeopathic Medical College.  For several years he practiced medicine and from 1891 to 1893 taught botany at West Virginia University.  In 1894 he was appointed curator of the department of botany of the Field Museum of Natural History; from 1897 to 1923 he was professor of medical botany at the Chicago Homeopathic Medical College.  He was also lecturer on botany at the University of Chicago.  Millspaugh carried on explorations in the West Indies, Brazil, and other parts of South America, and was the author of "American Medical Plants" (1887); "Flora of West Virginia" (1891); and many articles in scientific and popular journals.