Thanks for the welcome.
Mennoniteman -There are northern/ultra-northern pecan varieties that are grown as far north as Michigan, Iowa, even into portions of southern Canada(Ontario) - and, yes, many of them will do well in PA. In general, most produce smaller nuts than the Southern pecan varieties most are acquainted with, as they have to mature in a shorter growing season with fewer heat units/growing-degree days. By and large, these northern pecan varieties tend to have higher oil content, in my experience, than many of the Southern varieties.
One of the northern pecan varieties, 'Major', which originated 90 miles or so north of me in native pecan forest of the Green River delta, has been used extensively by the USDA pecan breeding program as a source of pecan scab resistance, in addition to superior kernel quality - 'Major' is a parent of 'Kanza', 'Lakota', 'Osage', among others. Recent genomic analysis of 'Major' indicates that it is actually a complex hican, with gene markers suggesting that it has both bitternut and shagbark hickory close up in its ancestry... possibly with a pecanX(bitternutXshagbark) cross a generation or two back.
Dr. Bill Reid, who recently retired as pecan specialist for KS & MO, has a very good Northern Pecan Blog, here:
http://northernpecans.blogspot.com/p/blog-page.html