Prunus spinosa the British Army, blackthorn sticks are carried by commissioned officers of the Royal Irish Regiment; this is a tradition also in Irish regiments in some Commonwealth countries. The leaves resemble tea leaves, and were used as an adulterant of tea. Shlomo Yitzhaki, a Talmudist and Tanakh commentator of the High Middle Ages, writes that the sap (or gum) of "P. spinosa" (which he refers to as the ) was used as an ingredient in the making of some inks used for manuscripts. The fruit stones have been found in Swiss lake dwellings. Evidence of the early use of sloes by
Prunus serrula typical of "Prunus", are produced in clusters of one to three. The fruit is a small oval bright red drupe. "Prunus serrula" is grown as a ornamental tree, especially for winter interest. It tolerates a variety of soil types and has a wide pH range. It prefers full sun and does well in USDA hardiness zones 5 to 8. Its potential as an invasive species is low, as it is susceptible to many common garden diseases and pests such as fire blight, powdery mildew and Japanese beetles. It is sometimes grafted to "Prunus serrulata" (Japanese cherry) crowns, forming a tree