1852, 1881  Is it to be like the big sap-trough in the sugar-bush at home?
1909  His sap-troughs . . . were full, as there was a good run of sap that spring.
1933  (1964)  The Mohawk Indians commonly used a hollowed-out basswood log for a sap trough, the log being burned out as much as possible and then cleaned out with a stone adze.