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                                                                 Exhibit 10(b).2

                            CERTIFICATION PURSUANT TO
                  SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002


I, Lisa J. Hartzell, Treasurer of Mairs and Power Growth Fund, Inc., certify
that:

1.   I have reviewed this report on Form N-CSR of Mairs and Power Growth Fund,
     Inc.

2.   Based on my knowledge, this report does not contain any untrue statement of
     a material fact or omit to state a material fact necessary to make the
     statements made, in light of the circumstances under which such statements
     were made, not misleading with respect to the period covered by this
     report;

3.   Based on my knowledge, the financial statements, and other financial
     information included in this report, fairly present in all material
     respects the financial condition, results of operations, changes in net
     assets, and cash flows (if the financial statements are required to include
     a statement of cash flows) of the registrant as of, and for, the periods
     presented in this report;

4.   The registrant's other certifying officer and I are responsible for
     establishing and maintaining disclosure controls and procedures (as defined
     in rule 30a-3(c) under the Investment Company Act of 1940) for the
     registrant and have:

     a)    designed such disclosure controls and procedures, or caused such
           disclosure controls and procedures to be designed under our
           supervision, to ensure that material information relating to the
           registrant, including its consolidated subsidiaries, is made known to
           us by others within those entities, particularly during the period in
           which this report is being prepared;

     b)    evaluated the effectiveness of the registrant's disclosure controls
           and procedures and presented in this report our conclusions about the
           effectiveness of the disclosure controls and procedures, as of a date
           within 90 days prior to the filing date of this report based on such
           evaluation; and

     c)    disclosed in this report any change in the registrant's internal
           control over financial reporting that occurred during the
           registrant's most recent fiscal half-year (the registrant's second
           fiscal half-year in the case of an annual report) that has materially
           affected, or is reasonably likely to materially affect, the
           registrant's internal control over financial reporting.

5.   The registrant's other certifying officer and I have disclosed to the
     registrant's auditors and the audit committee of the registrant's board of
     directors (or persons performing the equivalent functions):

     a)    all significant deficiencies and material weaknesses in the design or
           operation of internal control over financial reporting which are
           reasonably likely to adversely affect the registrant's ability to
           record, process, summarize, and report financial information; and

     b)    any fraud, whether or not material, that involves management or other
           employees who have a significant role in the registrant's internal
           control over financial reporting.


Date:        September 5, 2003
         ---------------------------

                                         /s/ Lisa J. Hartzell
                                      -----------------------------------------
                                             Lisa J. Hartzell, Treasurer