SECOND AMENDMENT TO SECOND AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT

Exhibit 10.34

SECOND AMENDMENT TO

SECOND AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT

THIS SECOND AMENDMENT TO SECOND AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT dated as of the 30^th day of December, 2015 (this “Amendment”) is by and among DELTIC TIMBER CORPORATION, a Delaware corporation (the “Borrower”), SUNTRUST BANK, in its capacity as Issuing Bank, Swingline Lender and Administrative Agent (the “Administrative Agent”) the financial institutions from time to time party to the Credit Agreement defined below (the “Lenders”), and the Lenders signatory hereto.

WHEREAS, the Borrower, the Lenders and the Administrative Agent are parties to that certain Second Amended and Restated Revolving Credit Agreement dated as of November 18, 2014, as amended by that certain First Amendment to Second Amended and Restated Revolving Credit Agreement dated as of August 25, 2015 (as so amended and as the same may be further amended, restated, supplemented or otherwise modified from time to time, the “Credit Agreement”);

WHEREAS, the Borrower has requested that the Administrative Agent and the Lenders agree to amend the Credit Agreement in certain respects on the terms and conditions hereof; and

WHEREAS, the Borrower, the Lenders and the Administrative Agent desire to amend certain provisions of the Credit Agreement on the terms and conditions contained herein.

NOW, THEREFORE, in consideration of the premises and for other good and valuable consideration, the receipt and adequacy of which are hereby acknowledged, the parties hereto agree as follows:

Section 1. Specific Amendment. Section 1.1 of the Credit Agreement is hereby amended by deleting the defined term “Revolving Commitment Termination Date” therein and substituting in lieu thereof the following:

“Revolving Commitment Termination Date,” or “Commitment Termination Date” means the earliest of (i) November 17, 2020; provided, that, if such date is extended pursuant to Section 2.27, such extended date as determined pursuant to such Section; provided, further, that, in each case, if such date is not a Business Day, such date shall be the next preceding Business Day, (ii) the date on which the Revolving Commitments are terminated pursuant to Section 2.8 or Section 8.1 and (iii) the date on which all amounts outstanding under this Agreement have been declared or have automatically become due and payable (whether by acceleration or otherwise).

Section 2. Acknowledgment and Agreement Regarding Extension. The parties hereto acknowledge and agree that, notwithstanding the notice or other requirements set forth in Section 2.27 of the Credit Agreement, this Amendment is intended to effect an extension of the Revolving Commitment Termination Date in accordance with Section 2.27 of the Credit Agreement. Accordingly, the parties hereto further agree that, notwithstanding any of the

requirements of Section 2.27 of the Credit Agreement: (i) this Amendment constitutes the Borrower’s first request to extend the Revolving Commitment Termination Date pursuant to Section 2.27 of the Credit Agreement and such extension request shall be deemed to have been made by the Borrower 45 days prior to the Revolving Commitment Termination Date (as in effect immediately prior to this Amendment); (ii) each Lender that executes this Amendment shall be deemed to be an “Extending Lender” for purposes of the Credit Agreement; and (iii) any Lender that does not execute this Amendment shall be deemed to be a “Non-Extending Lender” for purposes of the Credit Agreement.

Section 3. Representations and Warranties. To induce the Administrative Agent and the Lenders to enter into this Amendment, the Borrower hereby represents and warrants to the Administrative Agent and the Lenders that:

(a) Authorization. Each of the Borrower and the other Loan Parties have the right and power, and have taken all necessary action to authorize them, to execute and deliver this Amendment and to perform their respective obligations hereunder and under the Credit Agreement, as amended by this Amendment, and the other Loan Documents to which they are a party in accordance with their respective terms. This Amendment has been duly executed and delivered by a duly authorized officer of the Borrower and the Loan Parties and each of this Amendment and the Credit Agreement, as amended by this Amendment, is a legal, valid and binding obligation of the Borrower enforceable against the Borrower in accordance with its respective terms.

(b) Compliance with Laws. The execution and delivery by the Borrower and the other Loan Parties of this Amendment and the performance by the Borrower of this Amendment and the Credit Agreement, as amended by this Amendment, in accordance with their respective terms, do not and will not, by the passage of time, the giving of notice or otherwise: (i) require any consent or approval of, registration or filing with, or any action by, any Governmental Authority or violate any Requirements of Law applicable to the Loan Parties or any judgment, order or ruling of any Governmental Authority; (ii) violate or result in a default under any indenture, material agreement or other material instrument binding on the Loan Parties or any of their assets or give rise to a right thereunder to require any payment to be made by the Loan Parties; or (iii) result in the creation or imposition of any Lien on any asset of the Loan Parties.

(c) Reaffirmation. As of the date of this Amendment and after giving effect to this Amendment, the representations and warranties set forth in Article IV of the Credit Agreement are true and correct in all material respects (except to the extent that any such representation or warranty expressly relates to a specified earlier date, in which case such representation or warranty shall be true and correct as of such earlier date, and except for changes in facts and circumstances which are not prohibited by the terms of the Credit Agreement); and

(d) No Default. As of the date hereof and after giving effect to this Amendment, no Default or Event of Default shall exist.

Section 4. Payment of Expenses. The Borrower agrees to pay or reimburse the Administrative Agent for its reasonable out-of-pocket costs and expenses incurred in connection

with the preparation, negotiation, execution and delivery of this Amendment and the other documents and agreements executed and delivered in connection herewith, including reimbursement or payment of all reasonable fees, charges and disbursements of counsel to the Administrative Agent.

Section 5. Conditions. The effectiveness of this Amendment is subject to the truth and accuracy of the representations and warranties contained in Section 3 hereof and the satisfaction of the following conditions precedent:

(a) The Administrative Agent and the Lenders shall have received a counterpart of this Amendment duly executed by the Borrower, the Guarantors, the Required Lenders and the Administrative Agent;

(b) The Administrative Agent shall have received an officer’s certificate signed by a Responsible Officer substantively in the form of Exhibit A attached hereto;

(c) The Administrative Agent shall have received, for itself and on behalf of SunTrust Robinson Humphrey, Inc. (“STRH”) and the Lenders, the fees and expenses contemplated by (i) that certain engagement letter dated December 8, 2015 between STRH and the Borrower and (ii) Section 4 hereof; and

(d) The Administrative Agent shall have received such other documents as the Administrative Agent, on behalf of the Lenders, may reasonably request.

Section 6. Effect; Ratification.

(a) Except as expressly herein amended, the terms and conditions of the Credit Agreement and the other Loan Documents remain unchanged and continue to be in full force and effect. The amendments contained herein shall be deemed to have prospective application only, unless otherwise specifically stated herein. The Credit Agreement is hereby ratified and confirmed in all respects. Each reference to the Credit Agreement in any of the Loan Documents (including the Credit Agreement) shall be deemed to be a reference to the Credit Agreement, as amended by this Amendment.

(b) Except as expressly set forth herein, nothing contained herein shall be deemed to constitute a waiver of compliance with any term or condition contained in the Credit Agreement or any of the other Loan Documents, or constitute a course of conduct or dealing among the parties. The Administrative Agent and the Lenders reserve all rights, privileges and remedies under the Loan Documents.

(c) This Amendment constitutes the entire agreement and understanding among the parties hereto with respect to the subject matter hereof and supersedes any and all prior agreements and understandings, oral or written, relating to the subject matter hereof. This Amendment shall for all purposes be deemed to be a “Loan Document” under the Credit Agreement and entitled to the benefits thereof.

Section 7. Further Assurances. The Borrower agrees to, and to cause any Loan Party to, take all further actions and execute such other documents and instruments as the Administrative

Agent may from time to time reasonably request to carry out the transactions contemplated by this Amendment, the Loan Documents and all other agreements executed and delivered in connection herewith.

Section 8. Binding Effect. This Amendment shall be binding upon and shall inure to the benefit of the parties hereto and their respective permitted successors and assigns.

Section 9. Counterparts. This Amendment may be executed in any number of counterparts, each of which shall be deemed to be an original and shall be binding upon all parties, their successors and assigns. The exchange of copies of this Amendment and of signature pages by facsimile or .pdf via email transmission shall constitute effective execution and delivery of this Agreement as to the parties.

Section 10. Severability; Headings. Any provision of this Amendment which is prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such prohibition or unenforceability, without invalidating the remaining provisions hereof, and any such prohibition or unenforceability in any jurisdiction shall not invalidate or render unenforceable such provision in any other jurisdiction. The section and subsection headings used in this Amendment are for convenience of reference only and are not to affect the construction hereof or to be taken into consideration in the interpretation hereof.

Section 11. GOVERNING LAW. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES UNDER THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF GEORGIA.

Section 12. Definitions. Except as otherwise defined herein, capitalized terms used herein shall have the meanings ascribed thereto in the Credit Agreement.

IN WITNESS WHEREOF, the parties hereto have caused this Second Amendment to Second Amended and Restated Revolving Credit Agreement to be duly executed by their respective authorized officers as of the day and year first above written.

CONSENT OF GUARANTORS

The undersigned, each a Guarantor, as defined in the Subsidiary Guarantee Agreement, hereby execute this Amendment to evidence their consent thereto, as well as the transactions contemplated thereby, and agree that the Subsidiary Guarantee Agreement dated November 18, 2014, remains in full force and effect.

Each of the undersigned parties further: (i) agrees that the amendments contained in the Second Amendment to Second Amended and Restated Revolving Credit Agreement dated as of the date hereof shall not in any way affect the validity and/or enforceability of any Loan Document, or reduce, impair or discharge the obligations of such Person thereunder and (ii) reaffirms its continuing obligations owing to the Administrative Agent and the Lenders under each of the other Loan Documents to which such Person is a party.

Each of the undersigned hereby represent and warrant to the Administrative Agent and the Lenders that: (a) the execution and delivery by such Persons of this Consent of Guarantors is within the power (corporate or otherwise) and authority of such Persons, has been duly authorized and approved by all requisite action on the part of the such Persons, and does not and will not contravene, breach or conflict with any provision of applicable law or any of the charter or other organic documents of such Persons, or any indenture, agreement, instrument or undertaking binding on such Persons; (b) this Consent of Guarantors has been duly executed by such Persons; and (c) the Loan Documents remain in full force and effect and constitute the legal, valid and binding obligations of such Persons, enforceable in accordance with their terms, except as limited by bankruptcy, insolvency, reorganization, moratorium or similar laws relating to or affecting generally the enforcement of creditor’s rights.