Fruit globose, an inch in diameter, deep red with a heavy bloom; skin thick; flesh yellow, juicy, of good flavor; stone flattened, oval, slightly rugose, deeply grooved on the dorsal and ridged on the ventral edge.
The history and habitat of Orthosepala are given by Sargent as follows: “The history of this plant as I know it, is briefly this: In June, 1880, Dr. George Engelmann of St. Louis, sent to the Arnold Arboretum a package of seeds marked ‘Prunus, sp. southern Texas.’ Plants were raised from these seeds and in 1888, or earlier, they flowered and produced fruit, which showed that they belonged to a distinct and probably undescribed species. A name, however, was not proposed for it, and in 1888, probably, plants or seeds were sent to Herr Spath, of the Rixdorf Nurseries, near Berlin, where this plum was found in flower by Dr. Emil Koehne, who has described it under the name of Prunus orthosepala.”
Of the affinity of this species Sargent says: “Prunus orthosepala is a true plum, rather closely related to Prunus hortulana, from which it can be distinguished by the smaller number of glands of the petioles, by the eglandular calyx-lobes, the dark colored fruit and smoother stone.” As the writer has seen this plum growing in the Arnold Arboretum, Jamaica Plains, Massachusetts, and the City parks at Rochester, New York, it seems well worth cultivating. Mr. J. W. Kerr writes of it as follows:
“I have P. orthosepala fruiting here, and with me its fruit is exceptionally fine in quality, sparingly produced—attributable I believe to the fact that no variety stands near enough to it for proper inter-pollination. The trees are rather dwarfish in habit, close-headed, with fine clean foliage. The fruit is globular in form; size equal to fair specimens of Hawkeye or Wyant; skin a greenish-yellow, almost entirely covered with deep red.”
W. F. Wight of the United States Department of Agriculture has collected specimens of a cultivated plum, taken from the wild, locally known as the Laire, in Rooks and neighboring counties in Kansas, with foliage very similar to Prunus orthosepela. While the identity of Laire with the species under discussion cannot be established at this time, the reported source of the seeds, “southern Texas,” from which Prunus orthosepela was grown may be an error.
23. PRUNUS GRACILIS Engelmann and Gray
1. Engelmann and Gray Bost. Jour. Nat. Hist. 5:243. 1845. 2. Torrey Pac. R. Rpt. 4:83. 1854. 3. Britton and Brown Ill. Fl. 2:249, fig. 1897.
P. chicasa var. normalis. 4. Torrey and Gray Fl. N. Am. 1:407. 1840.
P. normalis 5. Small Fl. S. E. U. S. 572. 1903.
Shrub low, attaining a height of five or six feet; branches many, straggling, more or less spiny; branchlets at first densely tomentose or soft-pubescent, becoming glabrous; leaves small, ovate-lanceolate or oval, margins finely and evenly serrate, rather thick, texture harsh and firm; upper surface dark green, glabrous or nearly so at maturity, lower surface paler, soft-pubescent becoming nearly glabrous; petiole short and stout.