What is one of the possible reason silpuhim disapered

The main reason could be the overexploitation since Cyrenaica became a Roman senatorial province, and the abandonment of the previous strict control over its collection.

However, by the middle of the first century A.D., the silphium had all but vanished. The main explanation may be the overexploitation that has occurred since Cyrenaica became a Roman senatorial province, as well as the abandonment of the former tight regulation over its collection.

a.) it provides a clue to solve the mystery.

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