Exhibit 10.10

                     SUPPLEMENTAL RETIREMENT BENEFIT PLAN

      This Supplemental Retirement Benefit Plan (the "Plan") as adopted
effective as of November 12, 1991, and amended August 24, 1997 and March 4,
1999, by Mosinee Paper Corporation, a Wisconsin corporation, ("Mosinee") for
the purposes of providing deferred compensation in the form of supplemental
retirement benefits for San W. Orr, Jr.  ("Mr. Orr") in recognition of his
service to Mosinee as its Chairman of the Board of Directors is hereby further
amended as of this 16th day of December, 2005, effective as of January 1, 2005.

      1.    Normal Supplemental Retirement Benefit.  Beginning on the first day
of the first month following the last to occur of (a) Mr. Orr's termination of
employment with each of Mosinee, its parent, Wausau Paper Corp. ("Wausau"), and
each other member of the Controlled Group (as hereinafter defined) of which
Wausau is also a member or (b) Mr. Orr's 60th birthday, and continuing on the
first day of each succeeding month, Mosinee shall pay to Mr. Orr, if he is then
living, a monthly supplemental retirement benefit (Mr. Orr's "Normal
Supplemental Retirement Benefit") in an amount equal to 50% of one-twelfth of
Mr. Orr's highest final average W-2 compensation for the five consecutive
calendar year period in which such compensation was paid.  Mr. Orr's Normal
Supplemental Retirement Benefit shall not be reduced or offset by the amount of
any other payment then due him from Mosinee or any other plan or program now or
hereafter maintained by Mosinee.  For purposes of this Plan, the term
"Controlled Group" means Wausau and each other member of the controlled group
of corporations or other entities under common control to which Wausau belongs
for purposes of determining whether a separation from service has occurred
pursuant to Section 409A of the Internal Revenue Code of 1984, as amended, and
the regulations promulgated thereunder.

      2.    Surviving Spouse Benefit.  From and after the first day of the
first month following the later of (a) the month in which Mr. Orr's death
occurs or (b) the month in which Mr. Orr would have attained his 60th birthday
if Mr. Orr's death occurs before he has attained age 60, and continuing on the
first day of each succeeding month, Mosinee shall pay to Mr. Orr's spouse, if
then living (Mr. Orr's "Surviving Spouse"), a monthly benefit (the
"Supplemental Surviving Spouse Benefit") in an amount equal to 50% of the
Normal Supplemental Retirement Benefit to which Mr. Orr would have then been
entitled had he then been living.

      3.    Change in Control of Wausau.

            (a)   In the event a Change in Control of Wausau occurs prior to
      Mr. Orr's death, Mosinee shall pay to Mr. Orr a lump sum amount equal to
      the present value of Mr. Orr's Normal Supplemental Retirement Benefit, as
      determined hereunder, as of the first day of the first month following
      such Change in Control of Wausau on which Mr. Orr is neither an employee
      nor a director of Wausau or of any other member of the Controlled Group
      of which Wausau is a member, whether or not such Change in Control
      occurred prior to the date on which Mr. Orr shall have ceased to be an
      employee or a director of Wausau.  Upon payment of the lump sum amount
      provided for in this subparagraph (a), Mosinee shall have no further
      obligation to pay any benefits under this Plan.
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            (b)   In the event a Change in Control of Wausau occurs after Mr.
      Orr's death and whether or not the Supplemental Surviving Spouse Benefit
      shall have then become payable, Mosinee shall pay to Mr. Orr's Surviving
      Spouse, if then living, the present value of the unpaid Supplemental
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      Surviving Spouse Benefit. Upon payment of the lump sum amount provided
      for in this subparagraph (b), Mosinee shall have no further obligation to
      pay any benefits under this Plan.

            (c)   For purposes of this plan, a "Change in Control of Wausau"
      shall be mean the happening of any of the following events:

            (1)   The acquisition by any individual, entity or group (within
            the meaning of Section 13(d)(3) or 14(d)(2) of the Exchange Act (a
            "Person") of beneficial ownership (within the meaning of Rule 13d-3
            promulgated under the Exchange Act) of 20% or more of either (A)
            the then outstanding shares of common stock of Wausau (the
            "Outstanding Corporation Common Stock") or (B) the combined voting
            power of the then outstanding voting securities of Wausau entitled
            to vote generally in the election of directors (the "Outstanding
            Corporation Voting Securities"); excluding, however, the following:
            (i) any acquisition directly from Wausau other than an acquisition
            by virtue of the exercise of a conversion privilege unless the
            security being so converted was itself acquired directly from
            Wausau, (ii) any acquisition by Wausau, (iii) any acquisition by
            any employee benefit plan (or related trust) sponsored or
            maintained by Wausau or any entity controlled by Wausau, (iv) any
            acquisition pursuant to a transaction which complies with clauses
            (A), (B), and (C) of paragraph (3) of this Section 3(c), (v) except
            as provided in paragraphs (4) and (5), any acquisition by any of
            the Woodson Entities or any of the Smith Entities, or (vi) any
            increase in the proportionate number of shares of Outstanding
            Corporation Common Stock or Outstanding Corporation Voting
            Securities beneficially owned by a Person to 20% or more of the
            shares of either of such classes of stock if such increase was
            solely the result of the acquisition of Outstanding Corporation
            Common Stock or Outstanding Corporation Voting Securities by
            Wausau; provided, however, that this clause (vi) shall not apply to
            any acquisition of Outstanding Corporation Common Stock or
            Outstanding Corporation Voting Securities not described in clauses
            (1), (ii), (iii), (iv), or (v) of this paragraph (1) by the Person
            acquiring such shares which occurs after such Person had become the
            beneficial owner of 20% or more of either the Outstanding
            Corporation Common Stock or Outstanding Corporation Voting
            Securities by reason of share purchases by Wausau; or

            (2)   A change in the composition of the Board such that the
            individuals who, as of the Effective Date, constitute the Board
            (such Board shall be hereinafter referred to as the "Incumbent
            Board") cease for any reason to constitute at least a majority of
            the Board; provided, however, for purposes of the Plan, that any
            individual who becomes a member of the Board subsequent to the
            Effective Date
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            whose election, or nomination for election by
            Wausau's shareholders, was approved by a vote of at least a
            majority of those individuals who are members of the Board and who
            were also members of the Incumbent Board (or deemed to be such
            pursuant to this proviso) shall be deemed to be and shall be
            considered as though such individual were a member of the Incumbent
            Board, but provided, further, that any such individual whose
            initial assumption of office occurs as a result of either an actual
            or threatened election contest (as such terms are used in Rule 14a-
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            11 of Regulation 14A promulgated under the Exchange Act) or other
            actual or threatened solicitation of proxies or consents by or on
            behalf of a Person other than the Board shall not be so deemed or
            considered as a member of the Incumbent Board; or

            (3)   Consummation of a reorganization, merger or consolidation, or
            sale or other disposition of all or substantially all of the assets
            of Wausau or the acquisition of the assets or securities of any
            other entity (a "Corporate Transaction"); excluding, however, such
            a Corporate Transaction pursuant to which (A) all or substantially
            all of the individuals and entities who are the beneficial owners,
            respectively, of the Outstanding Corporation Common Stock and
            Outstanding Corporation Voting Securities immediately prior to such
            Corporate Transaction will beneficially own, directly or
            indirectly, more than 60% of, respectively, the outstanding shares
            of common stock and the combined voting power of the then
            outstanding voting securities entitled to vote generally in the
            election of directors, as the case may be, of the corporation
            resulting from such Corporate Transaction (including, without
            limitation, a corporation which as a result of such transaction
            owns or all or substantially all of Wausau's assets either directly
            or through one or more subsidiaries) (the "Resulting Corporation")
            in substantially the same proportions as their ownership,
            immediately prior to such Corporate Transaction, of the Outstanding
            Corporation Common Stock and Outstanding Corporation Voting
            Securities, as the case may be, (B) no Person (other than Wausau,
            any employee benefit plan (or related trust) of Wausau, any Woodson
            Entity, any Smith Entity, or such Resulting Corporation) will
            beneficially own, directly or indirectly, 20% or more of,
            respectively, the outstanding shares of common stock of the
            Resulting Corporation or the combined voting power of the then
            outstanding voting securities of such Resulting Corporation
            entitled to vote generally in the election of directors except to
            the extent that such ownership existed with respect to Wausau prior
            to the Corporate Transaction, and (C) individuals who were members
            of the Incumbent Board will constitute at least a majority of the
            members of the board of directors of the Resulting Corporation; or

            (4)   The Woodson Entities acquire beneficial ownership of more
            than 35% of the Outstanding Corporation Common Stock or Outstanding
            Corporation Voting Securities or of the outstanding shares of
            common stock or the combined voting
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            power of the then outstanding voting securities entitled to vote
            generally in the election of directors, as the case may be, of the
            Resulting Corporation; or

            (5)   The Smith Entities acquire beneficial ownership of more than
            35% of the Outstanding Corporation Common Stock or Outstanding
            Corporation Voting Securities or of the outstanding shares of
            common stock or the combined voting power of the then outstanding
            voting securities entitled to vote generally in the election of
            directors, as the case may be, of the Resulting Corporation; or

            (6)   The approval by the shareholders of Wausau of a complete
            liquidation or dissolution of Wausau.

            For purposes of this Section 3(c), the term "Woodson Entities"
<PAGE>
      shall mean Aytchmonde P. Woodson, Leigh Yawkey Woodson and Alice
      Richardson Yawkey, members of their respective families and their
      respective descendants (the "Woodson Family"), heirs or legatees of any
      of the Woodson Family members, transferees by will, laws of descent or
      distribution or by operation of law of any of the foregoing (including of
      any such transferees) (including any executor or administrator of any
      estate of any of the foregoing), any trust established by any of
      Aytchmonde P. Woodson, Leigh Yawkey Woodson, or Alice Richardson Yawkey,
      whether pursuant to last will or otherwise, any partnership, trust or
      other entity established primarily for the benefit of, or any other
      Person the beneficial owners of which consist primarily of, any of the
      foregoing or any Affiliates or Associates of any of the foregoing or any
      charitable trust or foundation to which any of the foregoing transfers or
      may transfer securities of Wausau (including any beneficiary or trustee,
      partner, manager or director of any of the foregoing or any other Person
      serving any such entity in a similar capacity).

            For purposes of this Section 3(c), the term "Smith Entities" shall
      mean David B. Smith and Katherine S. Smith, members of their respective
      families and their respective descendants (the "Smith Family"), heirs or
      legatees of any of the Smith Family members, transferees by will, laws of
      descent or distribution or by operation of law of any of the foregoing
      (including of any such transferees) (including any executor or
      administrator of any estate of any of the foregoing), any trust
      established by either of David B. Smith or Katherine S. Smith, whether
      pursuant to last will or otherwise, any partnership, trust or other
      entity established primarily for the benefit of, or any other Person the
      beneficial owners of which consist primarily of, any of the foregoing or
      any Affiliates or Associates of any of the foregoing or any charitable
      trust or foundation to which any of the foregoing transfers or may
      transfer securities of Wausau (including any beneficiary or trustee,
      partner, manager or director of any of the foregoing or any other Person
      serving any such entity in a similar capacity).

            For purposes of this Section 3(c), the terms "Affiliate" and
      "Associate" shall have the meanings ascribed to such terms in Rule 12b-2
      of the General Rules and Regulations under the Exchange Act as in effect
      on the date of this Plan.
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            (e)   For purposes of this Plan, the present value of Mr. Orr's
      Normal Supplemental Retirement Benefit or the Supplemental Surviving
      Spouse Benefit shall be determined by reference to the 1983 Individual
      Annuity Mortality Table with an assumed interest rate equal to the
      "immediate annuity rate" as then in effect as determined by the Pension
      Benefit Guaranty Corporation and promulgated in Appendix B to 29 C.F.R.
      '2619.65 or any successor regulation adopted for the same or
      substantially similar purpose.

      4.    Supplemental Retirement Benefits in Addition to Other Rights and
Benefits.  The rights and benefits conferred upon Mr. Orr (and Mr. Orr's
Surviving Spouse) pursuant to this Plan shall be in addition to all other
rights and benefits conferred upon Mr. Orr by Mosinee by reason of his
employment.

      5.    Nature of Mosinee's Obligations and Mr. Orr's Rights. Neither Mr.
Orr nor his Surviving Spouse, if any, shall acquire any right, title or
interest in the assets of Mosinee by reason of this Plan.  To the extent Mr.
Orr or his Surviving Spouse shall acquire a right to receive payments from
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Mosinee pursuant to this Plan, such right shall be no greater than the right of
any unsecured general creditor of Mosinee.

      6.    Assignment by Mr. Orr Prohibited.  This Plan and Mr. Orr's rights
and benefits hereunder (and the rights of his surviving spouse, if any) shall
not be subject to voluntary or involuntary sale, pledge, hypothecation,
transfer or assignment by Mr. Orr or such Surviving Spouse, their personal
representatives or heirs or any other person or persons or organization or
organizations succeeding to any of their rights and benefits hereunder.

      7.    Funding.  All benefits paid or payable pursuant to the terms of
this Plan shall be paid out of the general assets of Mosinee.

      8.    Claims Procedure.  The claims procedure set forth in the Wausau
Paper Corp. Retirement Plan or any successor to such plan is incorporated
herein by this reference as the claims procedure for this Plan.

      9.    Plan Administrator.  The plan administrator and named fiduciary of
this Plan shall be Mosinee.

      10.   Binding Effect.  This Plan shall be binding upon and inure to the
benefit of (1) Mr. Orr and his Surviving Spouse and their personal
representatives and heirs and any other person or persons or organization or
organizations succeeding to any of Mr. Orr's rights or benefits hereunder, and
(2) Mosinee and its successors and assigns.

      11.   Severability.  The invalidity or unenforceability of any provision
of this Plan shall not invalidate or render unenforceable any other provision
of this agreement.
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      12.   Governing Law.  This Plan shall be governed by the Employee
Retirement Income Security Act of 1974, as amended, and to the extent not
preempted by such Act, by the laws of the State of Wisconsin.

      13.   Section 409A Compliance.  Notwithstanding any other provisions of
the Plan, no distribution otherwise provided for by this Plan shall be made if
such distribution would cause the Plan to fail to meet the requirements of
Section 409A of the Internal Revenue Code of 1986, as amended (the "Code") and
cause the Participant to be subject to the interest and additional tax imposed
pursuant to Code Section 409A(a)(1)(B), and any such distribution shall be
modified so that such distribution will then comply with the requirements of
Code Section 409A so as to preclude the application of Code Section
409A(a)(1)(B); including, if required, the deferral of any distribution for a
period of not less than six months following the Termination of Employment of a
Participant who was a key employee, as determined pursuant to Code Section
409A.

      IN WITNESS WHEREOF, Mosinee has caused this agreement to be executed by
its President thereunto duly authorized as of the 12th day of December, 2005.

                                    MOSINEE PAPER CORPORATION


                                    By:
                                           Thomas J. Howatt
                                           As its President and Chief Executive
                                           Officer
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