Root-Grafting of Dahlia
Grafting is a method of asexual plant propagation widely used in agriculture and horticulture where the tissues of one plant are encouraged to fuse with those of another. Pictured here is the root-grafting of a dahlia.
Encyclopaedia Britannica (11th ed., vol. 13) (New York, NY: The Encyclopaedia Britannica Company, 1910)