What are the other types of “cedar” and are they good or bad for fence posts?
Red cedar (http://en.wikipedia.org/wiki/Juniperus_virginiana) & Pencil cedar can be used, but you need to look at it for the big hearts as it may not last in an outside environment as long as the “mountain cedar” would. These cedars are aromatic and excellent for indoor uses, such as furniture or pencils. You will need to determine how long you want that fence to stay. If you use class 1 galvanized wire that will last 15 years or less, then the fence post doesn’t really have to last longer than 15 years. If you use class 3 galvanzied wire that should last 25+ years, then you want your posts to hold up as long as or longer than the wire.