פירוש על עבודה זרה 84:8

The Talmud rejects the proof that R. Yohanan brought that the twigs must have come from another tree. One could say that the twigs came from the same tree that was dedicated but that the branches grew after the tree had been dedicated. This baraita might hold that while one should not use such twigs, if one does this does not constitute “trespass.” But if the twigs come from that same tree, then they would also come from the asherah tree and this would prove that an idol that broke on its own accord may be used. In the case of the asherah tree, it would not matter when they grew. They should always be prohibited.