Some key features of the leaf of Prunus caroliniana are two little glands that project from the edges of the petiole underneath the base of the blade, incurved, callous teeth along the margins, and a band of hairs on either side of the mid-vein on the top surface (Radi et. al 2004: 595). These features were used to distinguish P. caroliniana from Prunus serotina, black cherry, partially-digested leaf remnants. Prunus serotina can cause black cherry intoxication in goats via digestion of the leaves (Radi et al., 2004: 593, 595).
Trees, including the P. caroliniana, are very important to society due to their ability to intercept rain (Xiao & McPherson, 2002: 291). The canopy intercepts raindrops as they fall, thus preventing rainfall from reaching the ground all at once and increasing the potential of erosion, flooding and pollution from stormwater runoff (Xiao & McPherson, 2002: 291-292). Using a rainfall interception model, Xiao & McPherson (2002: 301) calculated that street and park trees in Santa Monica, CA, intercept 1.6% of annual precipitation with runoff benefit of $3.80 per tree.
Radi, Z., Styer, E. & Thompson, L. 2004. Prunus spp. intoxication in ruminants: a case in a goat and diagnosis by identification of leaf fragments in rumen contents. Journal of Veterinary Diagnostic Investigation 16: 593-599.
Xiao, Q. & McPherson, E. G. 2002. Rainfall interception by Santa Monica’s municipal urban forest. Urban Ecosystems 6: 291-302.
I believe the petiole glands and fuzzy lower midrib belong to Prunus serotina instead. I've seen them on it (especially on young leaves) and not on Prunus caroliniana. See these net sources: http://departments.bloomu.edu/biology/ricketts/Prunus/P_sero/P_sero.html https://fp.auburn.edu/sfws/samuelson/dendrology/rosaceae_pg/black_cherry.htm