Exhibit 23.1 CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM We consent to the incorporation by reference in Registration Statement No. 333-16359 on Form S-8 of UnionBancorp, Inc. of our report dated February 18, 2005 appearing in this Annual Report on Form 10-K of UnionBancorp, Inc. for the year ended December 31, 2004. Crowe Chizek and Company LLC Oak Brook, Illinois March 24, 2005