I checked with Steve Krauth, Curator at the UW-Madison Research Collection and he agrees with my ID. He sent me this URL: http://spiders.entomology.wisc.edu/Araneidae/Araneus_trifolium/index.html I'm also checking with Mike Draney, a spider expert out of UW-Green Bay.

but unfortunately that's not the spider in your image. Araneus are notoriously difficult and variable spiders, but look at a dozen trifolium and another dozen diadematus, such as in the compilation John gathered for you below, and you will agree, we think, that your spider is diadematus. The next spider you posted was indeed a trifolium, an unusual all white form.