According to John Sorenson, two puzzling plants are mentioned in Mosiah 9:9, among those cultivated by the people of Zeniff: "sheum" and "neas." The former word has recently been identified as "a precise match for Akkadian s(h)e'um, 'barley' (Old Assyrian 'wheat'); the most popular ancient Mesopotamian cereal name." The word's sound pattern indicates it was probably a Jaredite term. This good North Semitic word was quite at home around the "valley of Nimrod," north of Mesopotamia, where the Jaredites paused and collected seeds before starting their long journey to America (Ether 2:1, 3). [John Sorenson, An Ancient American Setting for the Book of Mormon, F.A.R.M.S., p. 185]
“With Neas and with Sheum”
According to Hunter and Ferguson, the following are exclusively New World crops, and thus might fall into the category of "neas" and "sheum" (Mosiah 9:9): 1. maize or Indian corn, 2. potato, 3. sweet potato, 4. cassava, 5. lima bean, 6. common garden beans, 7. runner bean (scarlet runner bean), 8. tepari bean, 9. yam, 10. tomato, 11. pepper, 12. Jerusalem artichokes, 13. sunflower, 14. squash, 15. pumpkin, 16. fig-leaved pumpkin, 17. musky pumpkin, 18. peanut, 19. chayote, 20. papaya, 21. avocado, 22. pineapple, 23. custard apple, 24. sour-sop, 25. cherimoya, 26. guava, 27. cacao, 28. cashew, 29. sapote, 30. white sapote, 31. sapodilla, 32. mammei, 33. Mexican plum, (and others) [Milton R. Hunter and Thomas S. Ferguson, Ancient America and the Book of Mormon, p. 306]
“Sheum”
John Sorenson notes that many historical cases assure us that plant names can change under new circumstances. When new plants are encountered old names commonly are applied to them. For instance, after the Conquest, many Spanish names were applied to plants found in Mexico because of their similarities to those of Europe, such as "ciruelo," plum (tree), applied to the nonplum genus Spondias. Various other naming puzzles also occurred. The fruit of the prickly-"pear" cactus was called by the Spaniards "fig," even though a real native fig was present. Some Spaniards used the word "trigo," wheat, for maize (French peasants in recent times still called it "Turkish wheat" or "Roman wheat")
Within the Book of Mormon itself we discover an interesting case of a plant name changing. Mosiah 9:9 mentions "sheum" in a list of plants. The name rather obviously derives from Akkadian (Babylonian) "she'um," barley (Old Assyrian, wheat), "the most popular ancient Mesopotamian cereal name," A Jaredite source is logical, for that group departed from Mesopotamia, although the Book of Mormon reference is to a plant cultivated by the Zeniffites (a Nephite-"Mulekite" group) in the second century B.C. The term could not have meant "barley" or "wheat" among the Nephites because "sheum" is listed along with "barley," while "wheat" is named elsewhere without hint of any connection with "sheum" (Incidentally, careful reading of Mosiah 9:9 indicates that while "corn," "barley," and "wheat" were classified as "seeds," "neas" and "sheum" may be implied to be other than seeds.) Whatever crop was called "sheum," it is unlikely to have meant to the Zeniffites what it once had in Mesopotamia, barley or wheat, but had come to be applied (by the Jaredites?) to something else.
Plenty of other cultivated grains in ancient Mesoamerica might have been called sheum, or "wheat," or "barley." Some possibilities are:
1. amarangth (Amaranthus leucocarpus and A. cruentus);
2. huauzontle;
3. chia (Salvia hispanica or S. chian, used in greater quantity by the Aztecs than even amaranth);
4. Setaria or fox-tail millet (S. geniculata Beauvais);
5. 40-chromosome "perennial corn" (Zea perennis, a form of teosinte);
6. 20-chromosome "perennial corn" (Zea diploperennis, also a teosinte); and
7. Chalco teosinte (probably the food plat mentioned in Codex Vaticanus 3738 as "accentli").
These materials are cited to make the point that the archaeological inventory of Mesoamerican grains still remains to be completed, as well as to point to the problem of naming. [John L. Sorenson, "Viva Zapato! Hurray for the Shoe! in Review of Books on the Book of Mormon, Vol. 6, Num. 1, pp. 337-339]