Question: Does the parable of the allegory of the olive tree in Jacob 5 invite serious consideration of Joseph Smith’s claim that he translated rather than wrote the Book of Mormon?
Answer: Joseph Smith would not have known about the ancient horticultural practices of that time.
According to scholars Paul R. Cheesman and C. Wilfred Griggs, “At no point in the allegory does the author [recording the allegory] manifest general ignorance on the subject of olive culture. The numerous casual references to pruning, cultivating, fertilizing, grafting, preserving species by grafting, incompatibility, bud sprouts, root rejuvenation, double graftage, root-top growth balances, and invigoration from graftage of wild species are most interesting... by its accurate incorporation of ancient horticultural practices, invites serious consideration of Joseph Smith’s claim that he translated rather than wrote the Book of Mormon.”
Source: 400 Questions and Answers About the Book of Mormon by Susan Easton Black, p. 119.