Buckberg's "geographic organization" theory is based on the assumption that cacti originated in the Central American-Caribbean region and migrated independently to the north and south. We now know that cacti originated in South America (after separation from the continental plate). Many researchers (hobbyists) of non-professional scientists appreciate the simplicity of this theory, which in many ways is clearly artificial.
In fact, few of his new genera stand up to modern researchers. Commenting on Buckberg's contribution, Hunt (1991a, 152) said that he "named another 78 genera, named or renamed 1200 species, and to my knowledge, he has never made (or cited) specimens." He left behind a 4,000-page, six-volume Cactus Family treatise, as well as a series of confusing naming records that could haunt the taxonomy of cacti for centuries."
Despite the many criticisms that Buckberg received during his lifetime and in his later life, his many detailed observations provide a wealth of potentially useful data sources, and although these observations must be rigorously evaluated, not all studies are designed to correct many of the mistakes he made, and his writings are sure to have a lasting place in the history of cactus research.
The Austrian botanist Franz Buxbaum was a contemporary of Buckberg, but he classified cacti in a completely different way. He classified the cactus family more naturally than anyone before him. Bacchus-Baum has spent years studying the morphology of cacti, especially flowers and seeds. Due to the interruption of the war, Bacchus-Baum's "Morphological Studies" were published until the English edition in 1950 and the German edition in 1957-1960, providing researchers with a wealth of theoretical knowledge. Based on his work on cacti, Bacchus Baum and Johannes Endler published the phylogenic theoretical approach to the family in 1955, which was revised in many subsequent years (Endler and Buxbaum 1982).
His phylogenetic theory is also an important basis for dealing with the specific classification of the cactus family, and the book Die Kakteen (in German, cactus), edited by Hans Krainz, was published continuously from 1956 to 1975.
(To be continued)