I nearly blushed reading this. "Pubescent stipules INDEED!:
"Description---A small tree, 15 to 20 feet high, with numerous spreading branches without spines, young branches smooth, leaves small, alternate on longish petioles, provided with linear, fimbriated, pubescent stipules which are quickly deciduous, blade about 2 inches long, oval, acute at both ends, crenatedentate, smooth above, more or less pubescent underneath, convolute in the bud, flowers appear before leaves. The cultivated plum has been developed from the wild plum, the thorns being lost in the process. Plums were known to the Romans in Cato's time."