MWANZA, April 22 -- In the quiet stretches of Rubya Forest Plantation in Ukerewe District, Mwanza Region, a routine economic activity has taken on an unexpected second life. What began as a strictly commercial tree sap harvesting venture has gradually evolved into a modest yet intriguing tourist attraction, drawing curious visitors to witness a process that is as methodical as it is visually striking. Ordinarily, tree sap harvesting is not the sort of activity that inspires sightseeing.

It is repetitive, technical, and largely unnoticed outside industrial supply chains. Yet in Rubya, the act of carefully slicing tree bark has produced a distinctive pattern—one that resembles the pages of an open book etched into the trunk.

The res...