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"Fahlias and paeonies may be grafted by inserting young shoots into the neck of one of the fleshy roots of each kind respectively the best method of doing so being to cut a triangular section near the upper end of the root, just large enough to admit the young shoot when slightly pared away in two sides to give it a similar form." — Encyclopedia Britannica, 1893

Root-Grafting

"Fahlias and paeonies may be grafted by inserting young shoots into the neck of one of the fleshy roots…