She nexts links the theme of the fruit-bearing tree to the notion of  mother earth as fruit-bearer with an image related to Eleusinian rites depicting Gaia rising from the earth holding a cornucopia from which emerges a child.

To reinforce the link between earth goddes and fruit tree, she points to a signet-ring from Mycenae.From the Acropolis treasure of Mycenae. Grave Circle A. 15th cent.BC. National Archaeological Museum of Athens.

Gold Signet ring - Mycenae

She further illustrates the notion of tree-worship with the example of a gold signet-ring from Mycenae (p. 166).

Coins from Ilium

There is a series of coins from Ilium (Ilion) that depict various phases of a bull and cow sacrifice ritual by Athena Ilias. The Bull is eventually suspended from a tree, the bottom part resting on a column. She describes this as a vegetation, tree and fruit ceremony.

Hagia Triada Sarcophagos - Jane Ellen Harrison

In Chapter VI of Themis,  Jane Ellen Harrison gives an extensive comparative analyis of the Hagia Triada Sarcophagus (the two main scenes pictured above).

She gives various examples of comparable scenes. Plato's Critias (119d-e) describes a bull sacrifice where the blood of the victim must touch a column where the laws Poseidon (who often is associated with a bull in Greek mythology) are inscribed as well as a curse.  Bulls ranged free in the sanctuary of Poseidon and ten kings, after prayers, had to hunt down a bull for the sacrifice. After a bowl was filled with wine and each king puts a clot of blood in it, they drink swearing an oath to obey the laws.