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                                                                  EXHIBIT 4.C.1



                        SENIOR NOTE AGREEMENT AMENDMENT


                        PLUM CREEK TIMBER COMPANY, L.P.
                                999 THIRD AVENUE
                           SEATTLE, WASHINGTON 98104

                                                    As of May 20, 1994
To each of the Purchasers
         listed on the attached
         Purchaser Schedule

Dear Purchaser:

                                    RECITALS

         WHEREAS, you and Plum Creek Timber Company, L.P., a Delaware limited
partnership (the "Company"), have entered into Senior Note Agreements dated as
of May 31, 1989 and as amended to the date hereof by amendments thereto dated
as of January 1, 1991, April 22, 1993 and September 1, 1993 (the "Senior Note
Agreements") pursuant to which the Company issued its 11-1/8% Senior Notes due
June 8, 2007 (the "Senior Notes");

         WHEREAS, Plum Creek Manufacturing, L.P., a Delaware limited
partnership ("Manufacturing"), is the obligor with respect to certain 11-1/8%
First Mortgage Notes due June 8, 2007 (the "Mortgage Notes"), pursuant to
certain Mortgage Note Agreements, dated May 31, 1989 and as amended to the date
hereof by amendments thereto dated as of January 1, 1991, April 22, 1993 and
September 1, 1993, among Manufacturing, the Company and the several holders of
the Mortgage Notes identified on the Purchaser Schedule attached thereto
("Mortgage Note Agreements");

         WHEREAS, the Company purchased certain timberlands in the State of
Montana ("Champion Timberlands") from Champion International Corporation;

         WHEREAS, the Company, in order to finance the purchase of the Champion
Timberlands, entered into a Revolving Credit Agreement dated as of October 28,
1993 with Bank of America National Trust and Savings Association and the other
lenders parties to such facility ("Bank of America Revolving Credit
Agreement");

         WHEREAS, the Company, in order to refinance a portion of the borrowing
under the Bank of America Revolving Credit Agreement, proposes to enter into
Senior Note Agreements with certain lenders (the "1994 Senior Note
Agreements").

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         WHEREAS, concurrently with the execution and delivery of this
Agreement, Manufacturing is executing and delivering a Mortgage Note Agreement
Amendment ("Mortgage Note Amendment Agreement") with the Required Holders (as
defined in the Mortgage Note Agreement) of the Mortgage Notes;

         WHEREAS, consummation of certain of the foregoing transactions
requires certain amendments to the Senior Note Agreements;

         NOW, THEREFORE, the Company hereby agrees with you that this Agreement
shall become effective as of the date on which (a) the 1994 Senior Note
Agreements are effective and (b) the conditions to effectiveness set forth in
Section 2 hereof are completely satisfied (the "Effective Time") and that
thereafter, all references to, and actions taken in connection with, the Senior
Note Agreements shall incorporate this Agreement in its entirety.  All
capitalized terms used in this Agreement and not otherwise defined have the
meanings ascribed to them in the Senior Note Agreements.

1.       CERTAIN AMENDMENTS

         A.      DEFINITIONS

                 (1)      The following definitions shall be added to Paragraph
10B of the Senior Note Agreements:

                          "1994 Senior Note Agreements" shall mean the senior
                 note agreements to be entered into between the Company and
                 certain lenders pursuant to which the Company shall issue, and
                 the lenders shall purchase, senior notes of the Company in an
                 aggregate principal amount not to exceed $150,000,000.

                 (2)      The following definition contained in Paragraph 10B
of the Senior Note Agreements shall be amended to read as follows:

                          "Qualified Debt" shall mean, as to the Company, as of
                 any date of determination, without duplication, all
                 outstanding indebtedness of the Company for borrowed money,
                 including, without limitation, Debt represented by the Notes,
                 the Bank of America Revolving Credit Agreement and the 1994
                 Senior Note Agreements.

2.       CONDITIONS TO EFFECTIVENESS

         The amendments to the Senior Note Agreements and the other agreements
set forth herein shall become effective, subject to the fulfillment of the
following conditions to your 



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satisfaction or waiver by you thereof (as evidenced by your execution and 
delivery of this Agreement) on or prior to the Effective Time.

         A.      REPRESENTATIONS AND WARRANTIES; NO DEFAULT

         The representations and warranties contained in Paragraph 3 hereof
shall be true in all material respects on and as of the date of closing, except
to the extent of changes caused by the transactions herein contemplated; and
there shall exist on the date of closing no Event of Default or Default; and
you shall receive a duly executed officer's certificate, dated as of the
Effective Time, to both such effects.

         B.      CERTAIN AGREEMENTS

         Each of (i) this Agreement, (ii) the 1994 Senior Note Agreements, and
(iii) the Mortgage Note Amendment Agreement shall have been duly authorized,
executed and delivered by the parties thereto (other than you) and by the
Required Holders and shall be in full force and effect.

         C.      PROCEEDINGS

         All proceedings taken or to be taken in connection with the
transactions contemplated hereby and all documents incident thereto shall be
satisfactory in substance and form to you, and you shall have received all such
counterpart originals or certified or other copies of such documents as you may
reasonably request.

         D.      OTHER CONSENTS

         The Company shall have sent all notices, and received all consents,
approvals, waivers and other authorizations, that are necessary in connection
with the modifications contained herein, and no default, event of default,
material adverse change or other similar event or condition shall exist under
any Debt or any agreement or instrument relating thereto as at the Effective
Time.

3.       REPRESENTATIONS AND WARRANTIES

         The Company represents and warrants as follows:

         A.      ORGANIZATION

         The Company is a limited partnership duly organized, validly existing
and in good standing under the Delaware Revised Uniform Limited Partnership Act
and has all requisite partnership power and authority to own and operate its
properties, to conduct its business as now conducted and as proposed to be
conducted and to enter into this Agreement.





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         B.      QUALIFICATION

         The Company is duly qualified or registered for transaction of
business and in good standing as a foreign limited partnership in each
jurisdiction in which the failure so to qualify or be registered would have a
material adverse effect on the business, property or assets, condition or
operations of the Company, or on the ability of the Company to perform its
obligations under this Agreement, or, after giving effect to the transactions
contemplated hereby, the Senior Note Agreements or the Senior Notes.

         C.      SUBSIDIARIES

         As of the Effective Time the General Partner owns a 2% general
partner's interest and the Company owns a 98% limited partner's interest in
Manufacturing, which interests have been duly authorized and validly issued,
fully paid and non-assessable and are owned free and clear of any Liens.
Manufacturing has issued no warrants or options to acquire, or instruments
convertible into or exchangeable for any equity interest in Manufacturing.  As
of the Effective Time the General Partner owns 4% of the capital stock and the
Company owns 96% of the capital stock of Marketing, which capital stock has
been duly authorized and validly issued, fully paid and non-assessable and are
owned free and clear of any liens.  Marketing has issued no warrants or options
to acquire or interests convertible into or exchangeable for any equity
interest in Marketing.  As of the Effective Time the Company has no
Subsidiaries other than Manufacturing and Marketing.  As of the Effective Time
Manufacturing has no Subsidiaries.

         D.      CHANGES, ETC.

         Except as contemplated by this Agreement, since March 31, 1994, the
date of the most recent combined financial statements of the Company, (a) the
Company has not incurred any material liabilities or obligations, direct or
contingent, or entered into any material transactions not in the ordinary
course of business, and (b) there has not been any material adverse change in
the business, properties or assets, condition (financial or otherwise) or
operations of the Company.

         E.      ACTIONS PENDING

         There is no action, suit, investigation or proceeding pending or, to
the knowledge of the Company, threatened against the Company, or any properties
or rights of the Company, by or before any court, arbitrator or administrative
or governmental body which questions the validity of this Agreement, or any
action taken or to be taken pursuant to this Agreement, which would be
reasonably likely to result in any material adverse change in the business,
properties or assets, condition (financial or otherwise) or operations of the
Company, or in the inability of the Company to perform its obligations under
this Agreement, the Senior Note Agreements or the Senior Notes, following the
effectuation of the transactions described herein.





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         F.      COMPLIANCE WITH OTHER INSTRUMENTS, ETC.

         The Company is not in violation of any provision of the Partnership
Agreement or of any term of any agreement or instrument to which it is a party
or by which it or any of its properties is bound or any term of any applicable
law, ordinance, rule or regulation of any governmental authority or any term of
any applicable order, judgment or decree of any court, arbitrator or
governmental authority (collectively, "term"), the consequences of which
violation would be reasonably likely to have a material adverse effect on its
business, properties or assets, condition (financial or otherwise) or
operations or on the ability of the Company to perform its obligations under
this Agreement, or, after giving effect to the transactions contemplated
hereby, the performance of the Senior Note Agreements or the Senior Notes, and
the execution, delivery and performance by the Company of this Agreement, or,
after giving effect to the transactions contemplated hereby, the Senior Note
Agreements or the Senior Notes will not result in any violation of or be in
conflict with or constitute a default under any such term or result in the
creation of (or impose any obligation on the Company to create) any Lien upon
any of the properties or assets of the Company, pursuant to any such term
except for Liens permitted by paragraph 6B(1) of the Senior Note Agreements;
and there is no such term which materially adversely affects or in the future
would be likely to materially adversely affect the business, properties or
assets, condition or operations of the Company or the ability of the Company to
perform its obligations under this Agreement, or, after giving effect to the
transactions contemplated hereby, the Senior Note Agreements or the Senior
Notes.

         G.      GOVERNMENTAL CONSENT

         No consent, approval or authorization of, or declaration or filing
with, any governmental authority is required for the valid execution, delivery
and performance by the Company of this Agreement, or, after giving effect to
the transactions contemplated hereby, the Senior Note Agreements or the Senior
Notes other than those which have been obtained on or prior to the Effective
Time.

         H.      FOREIGN ASSETS CONTROL REGULATIONS, ETC.

         The execution and delivery of this Agreement by the Company and the
consummation of the transactions contemplated hereby will not violate the
Foreign Assets Control Regulations, the Transaction Control Regulations, the
Cuban Assets Control Regulations, the Foreign Funds Control Regulations, the
Iranian Assets Control Regulations, the Nicaraguan Trade Control Regulations,
the South African Transactions Regulations, the Libyan Sanctions Regulations,
the Soviet Gold Coin Regulations or the Panamanian Transactions Regulations of
the United States Treasury Department (31 C.F.R., Subtitle B, Chapter V, as
amended) or (i) Executive Orders 12722 and 12724 (55 Fed. Reg. 31803 and 55 Fed
Reg.  33089), Blocking Iraqi Government Property and Prohibiting Transactions
with Iraq, and (ii) Executive Orders 12723 and 12725 (55 Fed.





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Reg. 31805 and 55 Fed. Reg. 33091), Blocking Kuwaiti Government Property and
Prohibiting Transactions with Kuwait.

         I.      AUTHORIZATION; ENFORCEABILITY

         This Agreement has been duly authorized by all requisite action and
duly executed and delivered by authorized officers of the Company and the
General Partner, and the Senior Note Agreements, as amended by this Agreement,
are valid obligations of the Company, legally binding upon and enforceable
against the Company in accordance with their terms, except as such
enforceability may be limited by (i) bankruptcy, insolvency, reorganization or
other similar law affecting the enforcement of creditors' rights generally and
(ii) general principles of equity (regardless of whether such enforceability is
considered in proceeding in equity or at law).

         J.      DISCLOSURE

         Neither this Agreement nor any other document, certificate or
statement furnished to you by or on behalf of the Company in connection
herewith contains any untrue statement of a material fact or omits to state a
material fact necessary in order to make the statements contained herein and
therein not misleading.  There is no fact peculiar to the Company which
materially adversely affects or in the future may (so far as the Company can
now reasonably foresee) materially adversely affect the businesses, property or
assets, condition (financial or otherwise) or results of operations of the
Company and which has not been set forth in this Agreement, or in the other
documents, certificates and statements furnished to you by or on behalf of the
Company, prior to the date hereof in connection with the transactions
contemplated hereby.

4.       EXPENSES; INDEMNIFICATION

         The Company shall, whether or not the transactions contemplated hereby
are consummated, save each holder of Senior Notes harmless for all
out-of-pocket expenses arising in connection with the execution and delivery or
performance of this Agreement, including the reasonable fees and expenses of
special counsel for the holders of Senior Notes.  The Company shall also
indemnify and save each holder of Senior Notes harmless from and against all
liabilities, obligations, losses, damages, penalties, actions, judgments,
suits, costs, expenses or disbursements of any kind whatsoever (including,
without limitation, any taxes, and any additional taxes imposed on any amounts
payable pursuant to this Paragraph 4) which may at any time be imposed on,
incurred by or asserted against any holder of Senior Notes in any way arising
out of, relating to or resulting from this Agreement or the transactions
contemplated hereby.  The obligations of the Company under this Paragraph 4
shall survive the transfer of any Senior Note or portion thereof or interest
therein by a holder of Senior Notes or any transferee and the payment of any
Senior Note.





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5.       MISCELLANEOUS.

         A.      CONTINUITY AND INTEGRATION OF AGREEMENTS.

         The Senior Note Agreements, as affected by this Agreement, shall
remain in full force and effect and are hereby ratified and confirmed, and the
Senior Note Agreements and this Agreement shall be deemed to be and are
construed as a single agreement.

         B.      SURVIVAL OF REPRESENTATIONS AND WARRANTIES.

         All representations and warranties contained herein shall survive the
execution and delivery of this Agreement, and the transfer of any Senior Note
by a holder thereof.  Such representations and warranties may be relied upon by
any transferee of a Senior Note from a holder thereof.

         C.      SUCCESSORS AND ASSIGNS.

         All covenants and agreements in this Agreement contained by or on
behalf of any of the parties hereto shall bind and inure to the benefit of the
respective successors and assigns of the parties hereto whether so expressed or
not.

         D.      DESCRIPTIVE HEADINGS.

         The descriptive headings of the several paragraphs of this Agreement
are inserted for convenience only and do not constitute a part of this
Agreement.

         E.      LIMITED DURATION

         This Agreement shall terminate and be of no further force or effect if
the Effective Time does not occur by November 30, 1994.

         F.      COUNTERPARTS.

         This Agreement may be executed in any number of counterparts and by
different parties hereto in separate counterparts, each of which when so
executed and delivered shall be deemed to be an original and all of which taken
together shall constitute but one and the same instrument.

         THIS AGREEMENT SHALL BE CONSTRUED AND ENFORCED IN ACCORDANCE WITH, AND
THE RIGHTS OF THE PARTIES SHALL BE GOVERNED BY, THE LAW OF THE STATE OF NEW
YORK.  THIS AGREEMENT SHALL BE BINDING UPON THE COMPANY AND THE HOLDERS OF
SENIOR NOTES AND THEIR RESPECTIVE SUCCESSORS AND ASSIGNS.





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         IN WITNESS WHEREOF, the parties hereto have executed this Agreement to
be effective as of the date first above written.

                                        PLUM CREEK TIMBER COMPANY, L.P.  
                                        By: Plum Creek Management Company, L.P.,
                                            General Partner


                                                  DIANE M. IRVINE
                                        By: ___________________________________
                                            Name: Diane M. Irvine 
                                            Title:   Vice President and Chief 
                                                     Financial Officer
The foregoing is accepted and agreed to:

TEACHERS INSURANCE AND ANNUITY
  ASSOCIATION OF AMERICA

            ANGELA BROCK-KYLE
By:  _______________________________
     Name:   Angela Brock-Kyle
     Title:  Associate Director
     Company:  Teachers Insurance and Annuity
               Association of America




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