AD&D 1e: N2 - THE FOREST ORACLE (1984)

From the cover:

The land lies under a curse. Fruit drops to the ground, its pulp black and rotten. Leaves curl and wither on the branches. Animals flee the parched vale, or starve.

Long ago, the Downs prospered under the care of Druids. But the priests of nature have retreated deep into the woods and rarely show themselves. One old man claims that the Druids have the power to save the valley, if only someone could find their Oracle to seek help. Will you reach the Forest Oracle of the Druids in time? And if you do, can they really lift the curse?

Or does the answer lie elsewhere?

Only the most daring and cunning adventurers will save the Downs. For character levels 2-4.