Exhibit (10)(o)(i)

EXECUTION COPY

FIRST AMENDMENT TO CREDIT AGREEMENT

THIS FIRST AMENDMENT TO CREDIT AGREEMENT (this “Amendment”) dated as of
February 20, 2007 to the Credit Agreement referenced below is by and among
(i) Potlatch Corporation (formerly known as Potlatch Holdings, Inc.), a Delaware
corporation (“Holdings”), (ii) Potlatch Forest Holdings, Inc. (formerly known as
Potlatch Operating Company and successor by way of merger to Potlatch
Corporation (the “Existing Potlatch” under the Credit Agreement referred to
below)), a Delaware corporation (“Potlatch Opco”), a wholly owned qualified REIT
subsidiary of Holdings, (iii) Potlatch Forest Products Corporation, a Delaware
corporation (“TRS”), a wholly owned taxable REIT subsidiary of Potlatch Opco
(collectively, the “Borrowers”), (iv) the Guarantors from time to time party
hereto, (v) the Lenders from time to time party hereto, and (vi) BANK OF
AMERICA, N.A., as Administrative Agent, Swing Line Lender and an L/C Issuer.

W I T N E S S E T H

WHEREAS, a $175 million revolving credit facility has been established in favor
of the Borrowers pursuant to the terms of that Credit Agreement dated as of
December 22, 2005 (as amended, restated, modified or supplemented from time to
time, the “Credit Agreement”) among the Borrowers, the Guarantors, the Lenders
identified therein (the “Lenders”) and the Administrative Agent;

WHEREAS, the Borrowers have requested that the Lenders amend the Credit
Agreement to modify certain provisions contained therein; and

WHEREAS, the Lenders have agreed to amend the Credit Agreement on the terms and
subject to the conditions set forth herein.

NOW, THEREFORE, IN CONSIDERATION of the premises and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto agree as follows:

1. Defined Terms. Capitalized terms used herein but not otherwise defined herein
shall have the meanings provided to such terms in the Credit Agreement.

2. Amendment. Subject to the satisfaction of the conditions precedent set forth
in Section 3 hereof, effective as of December 31, 2006, Section 1.01 of the
Credit Agreement is hereby amended by restating the definition of “Consolidated
Net Worth” in its entirety to read as follows:

“Consolidated Net Worth” means, as of any date, stockholders’ equity or net
worth of the Consolidated Parties on a consolidated basis, as of such date, as
determined

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in accordance with GAAP; provided, however, that for the purpose of calculating
Consolidated Net Worth with respect to Section 6.10(b) and the calculation of
the Funded Indebtedness to Capitalization Ratio (including in connection with
determining the Applicable Rate), such calculation shall be adjusted to exclude
that portion of “Accumulated other comprehensive income or loss” as shown on the
Borrowers’ consolidated balance sheet related to an underfunding or overfunding
of postretirement) benefit plans (i.e., there will be added back to Consolidated
Net Worth any such amount that is shown as a negative number and that relates to
an underfunding of such benefit plans and there will be subtracted from
Consolidated Net Worth any such amount that is shown as a positive number and
that relates to an overfunding of such benefit plans); provided further,
however, that the aggregate amount of all such amounts added back to
Consolidated Net Worth pursuant to this proviso after the 2005 fiscal year
(i.e., for fiscal year 2006 and beyond) shall not exceed $200,000,000.

3. Conditions Precedent. This Amendment shall become effective as of
December 31, 2006 upon receipt by the Administrative Agent of counterparts of
this Amendment duly executed by the Borrowers, the Guarantors and the Lenders.

4. Representations and Warranties. Each of the Borrowers and the Guarantors
hereby represents and warrants that (a) it has the requisite corporate power and
authority to execute, deliver and perform this Amendment, (b) it is duly
authorized to, and has been authorized by all necessary corporate action to,
execute, deliver and perform this Amendment, (c) no consent, approval,
authorization or order of, or filing, registration or qualification with, any
court or governmental authority or third party is required in connection with
the execution, delivery or performance by it of this Amendment, (d) the
execution, delivery and performance by it of this Amendment do not and will not
conflict with, result in a breach of or constitute a default under the articles
of incorporation, bylaws or other organizational documents of either the
Borrowers or the Guarantors or any of their Subsidiaries or any indenture or
other material agreement or instrument to which any such Person is a party or by
which any of its properties may be bound or the approval of any Governmental
Authority relating to such Person except as could not reasonably be expected to
have a Material Adverse Effect, (e) the representations and warranties contained
in Article V of the Credit Agreement are true and correct in all material
respects on and as of the date hereof as though made on and as of such date
(except for those which expressly relate to an earlier date) and (f) after
giving effect to this Amendment, no Default or Event of Default exists under the
Credit Agreement on and as of the date hereof or will occur as a result of the
transactions contemplated hereby.

5. No Other Changes; Ratification. Except as expressly modified hereby, all of
the terms and provisions of the Credit Agreement (including schedules and
exhibits thereto) and the other Loan Documents shall remain in full force and
effect. The term “this Agreement” or “Credit Agreement” and all similar
references as used in each of the Loan Documents shall hereafter mean the Credit
Agreement as amended by this Amendment. Except as herein specifically agreed,
the Credit Agreement is hereby ratified and confirmed and shall remain in full
force and effect according to its terms.

 

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6. Costs and Expenses. The Borrowers agree to pay all reasonable costs and
expenses of the Administrative Agent in connection with the preparation,
execution and delivery of this Amendment, including without limitation the
reasonable fees and expenses of Moore & Van Allen PLLC.

7. Counterparts; Facsimile; Email. This Amendment may be executed in any number
of counterparts, each of which when so executed and delivered shall be deemed an
original and it shall not be necessary in making proof of this Amendment to
produce or account for more than one such counterpart. Delivery of an executed
counterpart of this Amendment by telecopy or email (in PDF format) by any party
hereto shall be effective as such party’s original executed counterpart.

8. Governing Law. This Amendment shall be deemed to be a contract made under,
and for all purposes shall be construed in accordance with, the laws of the
State of New York.

9. Entirety. This Amendment and the other Loan Documents embody the entire
agreement between the parties and supersede all prior agreements and
understandings, if any, relating to the subject matter hereof. This Amendment
and the other Loan Documents represent the final agreement between the parties
and may not be contradicted by evidence of prior, contemporaneous or subsequent
oral agreements of the parties. There are no oral agreements between the
parties.

10. Acknowledgment of Guarantors. The Guarantors acknowledge and consent to all
of the terms and conditions of this Amendment and agree that this Amendment and
any documents executed in connection herewith do not operate to reduce or
discharge the Guarantors’ obligations under the Credit Agreement or the other
Loan Documents.

[SIGNATURE PAGES FOLLOW]

 

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IN WITNESS WHEREOF, each of the parties hereto has caused a counterpart of this
Amendment to be duly executed and delivered as of the date first above written.

 

BORROWERS:   POTLATCH CORPORATION,   formerly known as Potlatch Holdings, Inc.  
a Delaware corporation   By:  

/s/ Douglas D. Spedden

  Name:   Douglas D. Spedden   Title:   Treasurer  

POTLATCH FOREST HOLDINGS, INC.,

formerly known as Potlatch Operating Company

and successor by way of merger to Potlatch

Corporation (the “Existing Potlatch” under the

Credit Agreement)

  a Delaware corporation   By:  

/s/ Douglas D. Spedden

  Name:   Douglas D. Spedden   Title:   Treasurer   POTLATCH FOREST PRODUCTS
CORPORATION   a Delaware corporation   By:  

/s/ Douglas D. Spedden

  Name:   Douglas D. Spedden   Title:   Treasurer

POTLATCH CORPORATION

FIRST AMENDMENT TO CREDIT AGREEMENT

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ADMINISTRATIVE AGENT     AND LENDERS:  

BANK OF AMERICA, N.A.,

  as Administrative Agent   By:  

/s/ Anthea Del Blanco

  Name:   Anthea Del Blanco   Title:   Vice President

POTLATCH CORPORATION

FIRST AMENDMENT TO CREDIT AGREEMENT

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BANK OF AMERICA, N.A., as a Lender, an L/C Issuer and Swing Line Lender By:  

/s/ Michael Colon

Name:   Michael Colon Title:   Vice President

POTLATCH CORPORATION

FIRST AMENDMENT TO CREDIT AGREEMENT

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U.S. BANK NATIONAL ASSOCIATION By:  

/s/ Janice T. Thede

Name:   Janice T. Thede Title:   Vice President

POTLATCH CORPORATION

FIRST AMENDMENT TO CREDIT AGREEMENT

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WELLS FARGO BANK, N.A. By:  

/s/ Deborah S. Watson

Name:   Deborah S. Watson Title:   Senior Vice President

POTLATCH CORPORATION

FIRST AMENDMENT TO CREDIT AGREEMENT

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COÖPERATIEVE CENTRALE RAIFFEISEN-BOERENLEENBANK B.A. “RABOBANK INTERNATIONAL”
NEW YORK BRANCH, as Lender By:  

/s/ Terese Rowe

Name:   Terese Rowe Title:   Vice President By:  

/s/ Rebecca O. Morrow

Name:   Rebecca O. Morrow Title:   Executive Director

POTLATCH CORPORATION

FIRST AMENDMENT TO CREDIT AGREEMENT

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NORTHWEST FARM CREDIT

SERVICES, PCA

By:  

/s/ Jim D. Allen

Name:   Jim D. Allen Title:   Senior Vice President

POTLATCH CORPORATION

FIRST AMENDMENT TO CREDIT AGREEMENT

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CAPITAL FARM CREDIT By:  

/s/ Robert P. Abbott

Name:   Robert P. Abbott Title:   President Corporate Lending

POTLATCH CORPORATION

FIRST AMENDMENT TO CREDIT AGREEMENT

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STERLING SAVINGS BANK By:  

/s/ Jill Scheuermann

Name:   Jill Scheuermann Title:   Vice President

POTLATCH CORPORATION

FIRST AMENDMENT TO CREDIT AGREEMENT

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UNION BANK OF CALIFORNIA, N.A. By:  

/s/ Kevin Sullivan

Name:   Kevin Sullivan Title:   Senior Vice President

POTLATCH CORPORATION

FIRST AMENDMENT TO CREDIT AGREEMENT