I've had some trouble finding fat wood further north, I think maybe the trees decay too slow or they aren't as resinous(because of colder winters maybe?). But if you find a part of a log where a good sized branch came out of the trunk, I find the knot where the two cores comes together is a good spot to find it.
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A gentleman should always be able to break his fast in the manner of a gentleman where so ever he may find himself.--Good Omens