1. Quintinye Com. Gard. 67, 69. 1699. 2. Langley Pomona 95, Pl. XXV fig. III. 1729. 3. Duhamel Trait. Arb. Fr. 105, Pl. XVIII. 1768. 4. Kraft Pom. Aust. 2:45, Tab. 200 fig. 2. 1796. 5. Miller Gard. Dict. 3. 1807. 6. Forsyth Treat. Fr. Trees 20. 1803. 7. Pom. Mag. 1:33. 1828. 8. Lond. Hort. Soc. Cat. 148. 1831. 9. Prince Pom. Man. 2:60. 1832. 10. Downing Fr. Trees Am. 290. 1845. 11. Floy-Lindley Guide Orch. Gard. 287, 383. 1846. 12. Thomas Am. Fruit Cult. 344. 1849. 13. Elliott Fr. Book 416. 1854. 14. McIntosh Bk. Gard. 2:529. 1855. 15. Thompson Gard. Ass’t 515. 1859. 16. Mas Pom. Gen. 2:101. 1873. 17. Am. Pom. Soc. Cat. 36. 1877. 18. Hogg Fruit Man. 687. 1884. 19. Mathieu Nom. Pom. 423, 452. 1889. 20. Guide Prat. 161, 358. 1895.
Blue Perdrigon, of some 2. Blaue Kaiserin 19. Blue Imperatrice 9, 10, 12, 13, 14, 15, 17, 18. Blue Imperatrice 16, 19. Die Veischenfarbige Kaiserinnpflaume 4. Empress I. Empress 5, 6, 9, 18, 19. Fürsten Zwetsche 19. Fürstenzwetsche 20. Hoheitspflaume 19, 20. Imperatrice Blue 8. Imperatrice 7, 8, 9, 10, 12, 13, 14, 15, 18, 19. Imperatrice Violette 3, 16, 20. Imperatrice Violette 4, 7, 8, 9, 10, 11, 13, 14, 15, 18, 19. Late Red Imperial 9. Late Violet, of some 2. Prinzessin Pflaume 19. Prune d’Altesse? 9. Red Magnum Bonum 9. Red Imperial 9. Smith’s large October? 9. The Imperatrice Plum 7. Veritable Imperatrice 8, 10, 13, 14, 15, 19. Violette 8, 10, 13, 14, 15, 19. Violette Kaiserin 19. Violette Kaiserin 16, 20, Violet Empress 9, 19.
Imperatrice has been long known and widely grown but the variety has no especial cultural value in the United States, the fruit being too small and too poor in quality. If it has any merit, it is keeping quality, the fruit hanging well on the tree and keeping well, even improving after picking.
This is an old variety, well known in Austria, France and England during the Seventeenth and Eighteenth Centuries. Like most long-known varieties its nomenclature is badly confused. Writers have confounded it with Semiana, the Perdrigons, German Prune and other plums of similar appearance. Duhamel regarded this variety as Perdrigon Late, holding that the true Imperatrice is nearly round. Calvel, also, describes a roundish plum under this name in his Traite Complet sur les Pepinieres. It is probable, however, that both Duhamel and Calvel were mistaken as all other authors describe an obovate plum. This variety was introduced into America early in the last century but has never become popular. It is of interest, nevertheless, since it has been a leading European variety, is a parent of a number of other varieties and its name is given to a group of plums. The American Pomological Society added it to its fruit catalog list in 1877, but dropped it in 1883.
Tree large, vigorous, upright-spreading, productive; leaves obovate or oval, two and one-quarter inches wide, four and one-quarter inches long, slightly rugose; margin crenate; petiole one inch long, thick, tinged red, pubescent, glandless, or with one or two small glands usually at the base of the leaf.
Fruit late; one and one-half inches by one and three-eighths inches in size, roundish or ovate, purplish-black, overspread with medium thick bloom; flesh golden-yellow, rather dry, firm but tender, sweet; of fair quality; stone free, one inch by three-quarters inch in size, roundish-ovate, the surfaces often granular and with a reddish tinge.
IMPERIAL EPINEUSE
Prunus domestica
1. Cal. State Bd. Hort. 48, 50. 1897-98. 2. U. S. D. A. Div. Pom. Bul. 7:316. 1898. 3. Can. Exp. Farm Bul. 2nd Ser. 3:53 1900. 4. Bailey Cyc. Hort. 1378. 1901. 5. Wickson Cal. Fruits 221, 224. 1908.