This member has one to trade on her list: http://members.gardenweb.com/members/exch/mentha33/ Here is a link that might be useful: Mentha33's trade lists

1000 words: I had two ancient Paulownia's removed from the front yard when we moved into our new house in May of '07. I had the roots ground out as deep as the largest grinder would go. The roots shoots that came up that year were horrendous- one every foot covering the entire yard. It was literally a daily chore to keep up with them. They came up again equally as bad in '08. In '09 they slowed down a bit on my property but began seeking new areas as I saw them in neighbor yards as well- not only on the adjoining properties but across the street as well. Spring of '10- three full years since I had the trees taken out- and I am still getting shoots. THREE YEARS! They slowed down considerably but I still cut down one or two every couple of days. They are impossible to pull. I cut more root shoots this spring!!! 2011 Four. Full. Years. After the trees were removed. This tree is the devil!!! I tell you this not to discourage you but to let you know what you could be getting into. They are one tenacious tree.

I believe the situation in zone 5 is that the colder temperatures kill the plant back to the ground each year. Therefore, you only get new growth each year (kind of like a large shrub). Therefore it is likely that they won't flower for you (a good reason for the invasiveness not being an issue, eh?). If you like the effect of the large leaves (which some people do), Northern Catalpa might give you the same effect but it survives the winter and eventually blooms.

Sue, I think the leaf tip burn you see is from the boron in the water in Davis. This is different from salt damage, and is the limiting factor for alot of things that will do well in Sacramento that don't do as well in Davis. For anyone contemplating a Paulownia tree, they do best with lots of summer water, and locating them out of regular high winds. Also, being so fast growing they are weak wooded, so not so good where dropped branches can cause damage. They also benefit from regular structural pruning to avoid narrow angle branch crotches and double leaders. At least they are not an invasive pest species in a summer dry climate, and are absolutely gorgeous when planted against a backdrop of evergreens like pines or redwoods.