It sounds like an artifact I once saw that collected sap from rubber trees.
The horticulturalist drilled a small hole in the tree and inserted the tube. He
then nailed a small bucket below the tube and came back a day or so later to
collect the small buckets of sap. This was then processed to make rubber.
Depending on the location, various sap resins could be harvested for commercial
reasons.

Ron May
Legacy 106, Inc.