Green’s Dictionary of Slang

(US) begging.

1914		Dly Republican (Monongahela, PA) 30 Apr. 1/7: Two [soldiers] were discharged for being intoxicated, and [...] ‘stemming’ or begging in the streets.
1923		N. Anderson Hobo 55: He doesn’t feel mean when out begging or ‘stemming’.
1924		‘Digit’ Confessions of a Twentieth Century Hobo 12: Stemming...Begging, cadging.
1927		C. Samolar ‘Argot of the Vagabond’ in AS II:9 390: Dinging the stem is known as mooching, stemming and plinging.
1930		C.R. Shaw Jack-Roller 137: I went down the ‘main stem,’ and he, being unwise to ‘stemming,’ I directed his course of attack – telling him to beg at every bakery and butcher shop, while I received his goods and hid them.
1935		J. Conroy World to Win 57: ’Tis an elegant smell that mulligan’s got. Must be good stemmin’, eh?
1967		Ottowa Citizen (Ontario, Can.) 9 Dec. 63/3: Stemming — begging on the main stem — is dangerous; it can cost 30 days in jail.
1992		Boston Globe (MA) 21 Feb. 17/3: Luis, 33,and his wife, Donna, 34, have been stemming, or begging, at the intersection.