DEL Deltic Timber Corp. (delisted)

Notes to Financial Statements

December 31, 2015 and 2014

Note 1 – Description of Plan

The following description of the Thrift Plan of Deltic Timber Corporation (“the Plan”) provides only general information. Participants should refer to the plan document for a more complete description of the plan’s provisions.

General

The Plan is a profit sharing, defined contribution plan covering each employee who is scheduled to work, or actually does work, 1,000 or more hours per year, and becomes eligible to participate following the completion of 30 days of service. Employees hired or rehired on or after January 1, 2015, or enter or reenter covered employment on or after January 1, 2015, will be an Automatic Active Participant and will be eligible for Automatic Employer Contributions beginning on the first day of the month following the date of satisfaction of eligibility requirements. The Plan is subject to the provisions of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”).

The Plan is administered by Deltic Timber Corporation’s (“the Company”) Pension, Investment, and Employee Benefits Committee (“Plan Administrator”), whose members are appointed by the Company’s Board of Directors. SunTrust Bank (“SunTrust” or the “Trustee”), Nashville N.A. is the Plan’s trustee, and FASCore, LLC is the record keeper for the Plan.

Contributions

Contributions to the Plan include (a) employee tax-deferred, earnings-reduction contributions, (b) employee after-tax supplemental contributions, (c) employer matching safe harbor contributions, (d) rollovers from other qualified plans, and (e) Automatic Employer Contributions for employees hired or rehired on or after January 1, 2015.

A participant may contribute up to 50 percent of their eligible compensation to a tax-deferred account. Tax-deferred contributions may not exceed the annual Internal Revenue Service limit. The employer will make a safe harbor contribution on behalf of each participant who makes a tax-deferred contribution to the Plan. The safe harbor contribution will equal 100 percent of the first 5 percent of eligible compensation. In addition, for Automatic Active Participants the Automatic Employer Contribution is equal to four percent of the participants’ compensation for the pay period. Participants who have attained age 50 before the end of the plan year are eligible to make catch-up contributions. The employer may make additional voluntary matching contributions at its discretion. No such additional voluntary contributions were made in 2015. Participants may also contribute to an after-tax supplemental account not to exceed 10 percent of eligible compensation. After-tax supplemental contributions are not matched by the employer. Participants direct the investment of their contributions and employer matching contributions into various investment options offered by the Plan, including stock in the Company.

Participant Accounts

Each participant’s account is credited with the participant’s contributions and (a) the Company’s contribution and (b) Plan earnings, and charged with an allocation of administrative expenses. Allocations are based on participant’s portion of account balances, as defined. The benefit to which a participant is entitled is the benefit that can be provided from the participant’s vested accounts.

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THRIFT PLAN OF DELTIC TIMBER CORPORATION

Notes to Financial Statements

December 31, 2015 and 2014

Note 1 – Description of Plan (cont.)

Vesting

Effective January 1, 2005, the Plan was amended whereby participants working for the Company on that date became 100 percent vested in all previous matching employer contributions. Subsequently, participants who were employed on December 31, 2014 will continue to be immediately 100 percent vested in safe harbor contributions and in any additional voluntary matching contributions. For those employed on or after January 1, 2015, the employee will be 100 percent vested in the automatic employer contributions and the investment returns of the automatic employer contributions after the employee completes three years of service, or if the employee is employed by the employer on or after the employee’s normal retirement age.

Payment of Benefits

Upon attaining normal retirement age, disability or death, the participant (or his/her beneficiary) has the option to receive payment equal to the value of the participant’s account in a lump sum, in installment payments not to exceed 20 years with each annual installment equal to at least 5 percent of the account balance, or in a combination of lump sum and installments (for pre-1987 after-tax contributions). For termination of service for reason other than retirement, disability, or death, a participant may receive the value of the vested account balance as a lump sum distribution.

Although the Plan is designed specifically for retirement, a participant may request an in-service withdrawal from the Plan while actively employed. A participant may withdraw employee after-tax supplemental contributions, Pre-2005 employer matching contributions, Pre-1987 deductible contributions, or Post-1986 matching employee contributions at a minimum of $250. Withdrawals from these accounts are limited to once every 12 months. Pre-1987 matching employee contributions may be withdrawn at any time and at any amount. Participants may be required to bear the cost of any distribution fees associated with an in-service withdrawal.

A participant may withdraw employee tax-deferred contributions or rollovers from other qualified plans under IRS hardship provisions only. “Hardship” is an immediate and heavy financial need in one of the following areas: (1) medical expenses incurred or necessary for the employee, spouse or dependents, (2) cost directly related to the purchase of a principal residence (not including mortgage payments), (3) preventing foreclosure or eviction from employee’s principal residence, (4) tuition fees, related educational fees and room and board expenses for the next 12 months of post-secondary education for employee, spouse or dependents, (5) funeral or burial expenses for the employee’s deceased parent, spouse or dependent, or (6) principal residence repair that qualifies for the casualty deduction. If a hardship withdrawal is taken, contributions are suspended for 6 months.

Employer contributions, employee tax-deferred or account earnings withdrawn from the Plan may be subject to a 10 percent penalty tax if the participant is not 59 1/2 years old or permanently disabled or has died.

Forfeited Accounts

Forfeitures may arise if a participant’s separation of employment occurred prior to 2005. During 2015, $1,627 in forfeitures were used to pay administrative expenses. At December 31, 2015, there were $602 in forfeited non-vested accounts, while at December 31, 2014, there were none.

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THRIFT PLAN OF DELTIC TIMBER CORPORATION

Notes to Financial Statements

December 31, 2015 and 2014

Note 1 – Description of Plan (cont.)

Administrative Expenses

The Company pays most administrative expenses. Participant level fees are paid by the participant from the participant’s account within the Plan. In addition, certain investment related expenses are netted in the investment returns reported to the Plan.

Note 2 – Summary of Significant Accounting Policies

Basis of Accounting

The accompanying financial statements of the Plan have been prepared on the accrual basis of accounting.

Use of Estimates

The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of net assets available for benefits and changes therein. Actual results could differ from those estimates.

Investment Valuation and Income Recognition

The Plan’s investments are stated at fair value. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at measurement date. See Note 4 for information on fair value measurements.

Purchases and sales of securities are recorded on a trade-date basis. Net depreciation includes the Plan’s gains and losses on investments bought and sold as well as held during the year. Dividends are recorded on the ex-dividend date, and interest income is recorded on the accrual basis.

Excess Contributions Payable

Amounts payable to participants for contributions in excess of amounts allowed by the Internal Revenue Service are recorded as a liability with a corresponding reduction to contributions. There was no liability for excess contributions payable to participants at December 31, 2015 and the liability was $1,091 at December 31, 2014.

Payment of Benefits

Benefits are recorded when paid.

Recently Issued Accounting Pronouncements

The Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update (“ASU”) 2015-07, “Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or its Equivalent)”. The ASU eliminates the requirement to categorize investments in the fair value hierarchy if their fair value is measured at net asset value (“NAV”) per share (or its equivalent) using the practical expedient in FASB Accounting Standards Codification Topic 820, Fair Value Measurement. This update will be effective for the Plan on January 1, 2016.

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THRIFT PLAN OF DELTIC TIMBER CORPORATION

Notes to Financial Statements

December 31, 2015 and 2014

Note 2 – Summary of Significant Accounting Policies (cont.)

FASB issued ASU 2015-12, “Plan Accounting: Defined Benefit Pension Plans (Topic 960), Defined Contribution Pension Plans (Topic 962), Health and Welfare Benefit Plans (Topic 965): (Part I) Fully Benefit-Responsive Investment Contracts, (Part II) Plan Investment Disclosures, (Part III) Measurement Date Practical Expedient. Parts I and III are not applicable to the plan. The amendments in Part II of this update require that investments (both participant-directed and nonparticipant-directed investments) be grouped only by general type, eliminating the need to disaggregate the investments by nature, characteristics and risks. In addition, certain other investment disclosures are eliminated. This update will be effective for the Plan on January 1, 2016. This update is not expected to have a material impact on the Plan’s financial statements.

The following table presents the Plan’s investments with separate identification of those that represent five percent or more of the Plan’s net assets at December 31, 2015 and 2014:

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THRIFT PLAN OF DELTIC TIMBER CORPORATION

Notes to Financial Statements

December 31, 2015 and 2014

Note 4 – Fair Value Measurements

FASB Accounting Standards Codification (“ASC”) 820, “Fair Value Measurements and Disclosures,” establishes a framework for measuring fair value. That framework provides a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (level 1 measurement) and the lowest priority to unobservable inputs (level 3 measurements). The three levels of the fair value hierarchy under FASB ASC 820 are described below:

The asset’s or liability’s fair value measurement level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Valuation techniques used need to maximize the use of observable inputs and minimize the use of unobservable inputs.

Following is a description of the valuation methodologies used for assets measured at fair value.

There have been no changes in the methodologies used at December 31, 2015 and 2014.

Cash equivalents: Valued at cost, which approximates fair value.

Equity securities: Valued at the closing price reported on the active market on which the individual securities are traded.

Mutual funds: Valued at the daily closing price as reported by the fund. Mutual funds held by the Plan are open-end mutual funds that are registered with the Securities and Exchange Commission. These funds are required to publish their daily net asset value (“NAV”) and to transact at that price. The mutual funds held by the Plan are deemed to be actively traded.

The methods described above may produce a fair value calculation that may not be indicative of net realizable value or reflective of future fair values. Furthermore, while the Plan believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different fair value measurement at the reporting date.

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Note 5 – Income Tax Status

The Internal Revenue Service has determined and informed the Company by a letter dated December 1, 2011, that the Plan and related trust are designed in accordance with applicable sections of the Internal Revenue Code of 1986, as amended (“IRC”). The Plan has been amended since the date of this letter, however, the Plan Administrator believes that the Plan is designed and is currently operating in compliance with the applicable requirements of the IRC and therefore believes that the Plan is qualified.

U.S. generally accepted accounting principles require plan management to evaluate tax positions taken by the Plan and recognize a tax liability if the Plan has taken an uncertain position that more likely than not would not be sustained upon examination by the Internal Revenue Service. The Plan Administrator has analyzed the tax positions taken by the Plan and has concluded that as of December 31, 2015, there are no uncertain tax positions taken or expected to be taken that would require recognition of a liability or disclosure in the financial statements. The Plan is subject to routine audits by taxing jurisdictions; however, there are currently no audits for any tax periods in progress. The administrator believes it is no longer subject to income tax examinations for years prior to 2012.

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THRIFT PLAN OF DELTIC TIMBER CORPORATION

Notes to Financial Statements

December 31, 2015 and 2014

Note 6 – Related Party Transactions

Funds invested in the cash equivalent investment option are considered deposits of SunTrust Bank. SunTrust is the Trustee of the Plan; therefore, these transactions qualify as party-in-interest transactions. Additionally, investments in common stock of Deltic Timber Corporation, the Plan sponsor, are party-in-interest transactions.

Note 7 – Plan Termination

Although it has not expressed any intent to do so, the Company has the right under the Plan to discontinue its contributions at any time and to terminate the Plan subject to the provisions of ERISA.

Note 8 – Risks and Uncertainties

The Plan invests in various investment securities. Investment securities are exposed to various risks such as interest rate, market, and credit risks. Due to the level of risk associated with certain investment securities, it is at least reasonably possible that changes in the values of investment securities will occur in the near term and that such changes could materially affect participant’s account balances and the amounts reported in the statements of net assets available for benefits.

The following is a reconciliation of corrective distributions per the financial statements to Form 5500 for the year ended December 31, 2015:

Corrective distributions in the financial statements have been reduced by excess contributions payable as of December 31, 2014. The Form 5500 reports participant distributions on the cash basis.

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Administrative expenses are recorded on the cash basis in the Form 5500.

Note 10 – Subsequent Events

Effective January 4, 2016, the following target date funds were added to the Plan investment options for Plan participants, T. Rowe Price Retirement 2020 Fund (R), T. Rowe Price Retirement 2030 Fund (R), T. Rowe Price Retirement 2040 Fund (R), T. Rowe Price Retirement 2050 Fund (R), and the T. Rowe Price Retirement 2060 Fund (R).

Effective May 16, 2016, the MFS New Discovery Value Fund (R3) was added to the Plan as an investment option for Plan participants and the Royce Opportunity Fund Service was frozen to new contributions.

The Company has evaluated subsequent events through June 24, 2016, the date the financial statements were issued.

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SUPPLEMENTAL SCHEDULE

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