Answer: I suppose you could try to plant an apple tree from seed, although many are self sterile and are propagated by budding, grafting and rooted cuttings instead of by seeds. (Somehow I don't think Johnny Appleseed knew about this!)
To try it, you will need to find an apple so ripe that it falls to the ground in order to be sure the seeds are mature. The seeds (if they are viable) need several months of cold treatment in order to germinate, so you might simply plant the seeds outside this fall. They should germinate next spring. The resulting tree, if any, will most likely not produce apples as nice as the one you started with -- which is why apple trees are ususally purchased as bareroot or container grown trees.
There are many many types of apples available (here is a site with some common ones along with their uses and disease ratings: http://muextension.missouri.edu/xplor/agguides/hort/g06022.h...). You might wish to contact your County Extension (tel. 350-2540) for their current recommendations on varieties which do well in your local area along with the suggested spray routine and schedule for home orchardists.
Good luck with your apple tree!
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