The few verses in the Book of Mormon that provide details of plants, animals, and natural resources used or encountered by the Nephites are of considerable interest. One such verse follows immediately on arriving in what one assumes to be the New World: [W]e did find upon the land of promise, as we journeyed in the wilderness, that there were beasts in the forests of every kind, both the cow and the ox, and the ass and the horse, and the goat and the wild goat, and all manner of wild animals, which were for the use of man (1 Nephi 18:25).
Note these were "found," not introduced. And as "this land should be kept as yet from the knowledge of other nations" (2 Nephi 1:8), they weren't introduced by other visitors from the Old World. Recall as well that all of North America was covered by the waters of the Great Flood (Ether 13:2), so all animals would seemingly have to have been introduced post-Flood (following the text here, of course, not the accepted natural history of the Americas based on real-world evidence).
The term "forests" suggests North America, as do the terms "land of many waters" (Mosiah 8:8) and similar references (e.g., Mosiah 18). Two Nephite locations identified by Joseph Smith were the Hill Cumorah in New York and the grave of Zelph, "a white Lamanite," discovered in a mound near the Illinois River in the Midwest. The Zelph references have Joseph referring to Nephites spread from the Atlantic to the Rocky Mountains. So the text, confirmed by Joseph Smith, gives clear indications the setting of the Book of Mormon narrative is North America. Attempts to argue for a limited geography setting in some corner of Mesoamerica appear to be in direct conflict with Joseph Smith's beliefs, a difficulty not generally discussed by proponents of the limited geography model.
Given a North American setting, one might expect references to bison (or buffalo) or deer in the book, but no mention of either of these are found. On the other hand, the reference to "horse" in 1 Nephi 18:25 is puzzling, as the standard account has native North American horses dying out in the Pleistocene megafaunal extinction before 8000 BC and being reintroduced to the Americas only later by the Spaniards.
This just scratches the surface of an interesting topic by way of one verse, 1 Nephi 18:25. Interestingly, the Encyclopedia of Mormonism contains no articles on the botany, zoology, or natural history of the Americas according to the Book of Mormon -- incidental references in the articles on "Economy and Technology," "Archaeology," and "Geography" are as close as it gets. Good articles defending the mention of horses include Book of Mormon Anachronisms (explaining them) by Michael Ash at FAIR, and a short, unsigned article Horses in the Book of Mormon at FARMS. An interesting article showing what purports to be the Smithsonian's form letter given in response to inquiries on the Book of Mormon along with comments by BYU anthropologist John L. Sorenson is here.