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                                                                   EXHIBIT 10.1

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                              JLG Industries, Inc.
                     Supplemental Executive Retirement Plan

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                           Effective September 6, 2000


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                              JLG Industries, Inc.
                     Supplemental Executive Retirement Plan

                                TABLE OF CONTENTS

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                                                                           Page

Section 1. Establishment and Purpose of the Plan........................... 1
         1.1.     Establishment............................................ 1
         1.2.     Purpose.................................................. 1

Section 2. Participation by Eligible Executives............................ 1
         2.1.     Eligible Executives on Effective Date.................... 1
         2.2.     Eligible Executives After Effective Date................. 1
         2.3.     Written Proof of Participation Required.................. 1

Section 3. Accrued Benefit................................................. 1
         3.1.     Method of Determining Accrued Benefit.................... 1
         3.2.     Applicable Percentage.................................... 2
         3.3.     Final Average Compensation............................... 2
         3.4.     Required Reductions...................................... 2

Section 4. Retirement Benefits............................................. 3
         4.1.     Normal Retirement Benefit................................ 3
         4.2.     Late Retirement Benefit.................................. 3
         4.3.     Early Retirement Benefit................................. 4
         4.4.     Vested Retirement Benefit................................ 4
         4.5.     Disability Retirement Benefit............................ 4
         4.6.     Joint & Survivor Annuity Option.......................... 4
         4.7.     Lump Sum Option.......................................... 4

Section 5. Preretirement Death Benefits.................................... 4
         5.1.     Lump Sum Benefit......................................... 4
         5.2.     Annuity Options Available to Spouse Beneficiaries........ 5

Section 6. Nature of Participant's Interest in Plan........................ 5
         6.1.     No Right to Assets....................................... 5
         6.2.     No Right to Transfer Interest............................ 5
         6.3.     No Employment Rights..................................... 5
         6.4.     Withholding and Tax Liabilities.......................... 5


Section 7. Administration, Interpretation, and Modification of Plan........ 5
         7.1.     Plan Administrator....................................... 5



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         7.2.     Powers of Committee...................................... 6
         7.3.     Finality of Committee Determinations..................... 6
         7.4.     Incapacity............................................... 6
         7.5.     Amendment, Suspension, and Termination................... 6
         7.6.     Power to Delegate Board Authority........................ 6
         7.7.     Headings................................................. 6
         7.8.     Severability............................................. 6
         7.9.     Governing Law............................................ 6
         7.10.    Complete Statement of Plan............................... 6

Section 8. Terms Used in the Plan.......................................... 7
         8.1.     Gender and Number........................................ 7
         8.2.     Definitions.............................................. 7

Appendix A.  Accrued Benefit of Participants Before September 6, 2000......A-1
         A.1.     Introduction.............................................A-1
         A.2.     Definitions..............................................A-1
         A.3.     Applicable Percentage....................................A-1
         A.4.     Final Average Compensation...............................A-1
         A.5.     Required Reductions......................................A-1


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                              JLG INDUSTRIES, INC.
                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN

                           Effective September 6, 2000

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SECTION 1. ESTABLISHMENT AND PURPOSE OF THE PLAN.

         1.1. ESTABLISHMENT. Effective June 1, 1995, the Company established the
Plan for the benefit of the Participants and, in the case of Participants
described in Section 2.1, for the purpose of replacing their benefits under the
Prior Plan.

         1.2. PURPOSE. The Plan is an unfunded plan maintained primarily for the
purpose of providing deferred compensation to a select group of management and
highly compensated employees. The Plan provides supplemental retirement income
to Participants in excess of their employer-provided benefits under certain
other plans and arrangements up to the maximum benefit specified in the Plan.
The Plan also provides supplemental survivor's income to Participant's
Beneficiaries.


SECTION 2. PARTICIPATION BY ELIGIBLE EXECUTIVES.

         2.1. ELIGIBLE EXECUTIVES ON EFFECTIVE DATE. An employee who is an
Eligible Executive on the Effective Date will become a Participant in the Plan
beginning on the Effective Date if he agrees in writing to waive all rights he
may have under the Prior Plan.

         2.2. ELIGIBLE EXECUTIVES AFTER EFFECTIVE DATE. An employee who first
becomes an Eligible Executive after the Effective Date will not become a
Participant in the Plan unless the Compensation Committee, in its sole
discretion, permits him to do so. If the Compensation Committee does permit him
to participate in the Plan, the Eligible Executive will become a Participant in
the Plan on the date specified by the Compensation Committee in its sole
discretion.

         2.3. WRITTEN PROOF OF PARTICIPATION REQUIRED. No employee will become a
Participant in the Plan unless he and the Company execute a copy of the Plan
document recognizing his participation in the Plan. The executed copy will
constitute an agreement between the Company and the employee that binds both of
them to the terms of the Plan. Their agreement will be binding on their heirs,
executors, administrators, successors, and assigns, both present and future. The
executed copy must be signed on the Company's behalf by an authorized officer
(other than the employee) and by the employee on his own behalf. In the case of
an employee who becomes a Participant under Section 2.1, the executed copy will
also constitute his written agreement to waive all rights he may have under the
Prior Plan.


SECTION 3. ACCRUED BENEFIT.

         3.1. METHOD OF DETERMINING ACCRUED BENEFIT.

         (a) If an individual first became a Participant on or after September
6, 2000, his Accrued Benefit shall be determined as provided in this Section 3.
The Participant's Accrued Benefit under the Plan shall be a monthly benefit
equal to the Applicable Percentage of his Final Average Compensation,


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payable in the form of a Ten-Year Certain Life Annuity beginning on his Normal
Retirement Date, and reduced in accordance with Section 3.4.

         (b) The Accrued Benefit of an individual who first became a Participant
before September 6, 2000, shall be determined as provided in Appendix A of the
Plan.

         3.2. APPLICABLE PERCENTAGE. A Participant's Applicable Percentage is
the percentage specified by the Compensation Committee with respect to the
Participant for purposes of the Plan, as reflected in the written agreement
between the Company and the Participant executed in accordance with Section 2.3,
multiplied by the service fraction described in the following sentence. Unless a
different service fraction is specified in the written agreement between the
Company and the Participant, the numerator of the service fraction is the
Participant's Years of Service (not exceeding 20) when his employment with the
Company terminates, and the denominator of the service fraction is 20.

         3.3. FINAL AVERAGE COMPENSATION. A Participant's Final Average
Compensation is one-twelfth the average of his Annual Compensation for the 2
consecutive or nonconsecutive calendar years during which the average of his
Annual Compensation is the highest. The Annual Compensation of a Participant for
a calendar year is the amount of the Participant's base salary for the calendar
year and the amount of any cash bonus paid to him in the calendar year, each
including (i) amounts that are contributed, at the election of a Participant, on
behalf of the Participant to a cafeteria plan or a cash or deferred arrangement
and not included in the Participant's gross income for federal income tax
purposes by reason of section 125 or 402(e)(3) of the Code and (ii) compensation
deferred under the JLG Industries, Inc. Executive Deferred Compensation Plan (or
any successor thereto). Annual Compensation earned more than 10 years before the
year in which the Participant's employment with the Company terminates is
ignored. Annual Compensation does not include any amount realized as a result of
the grant, modification, or exercise of a stock option.

         3.4. REQUIRED REDUCTIONS. The monthly installments otherwise included
in a Participant's Accrued Benefit will be reduced as follows:

                  (a) First, if the Participant elects to begin receiving
          benefits before his Normal Retirement Date, his Accrued Benefit will
          be reduced by one half of one percent for each month during which
          benefits are scheduled to be paid before his Normal Retirement Date.

                  (b) Second, each monthly installment will be reduced by the
          monthly amount of a benefit that is the Actuarial Equivalent of all
          employer-provided benefits the Participant has received, is receiving,
          or is expected to receive under any defined benefit plan (other than
          this Plan) maintained by the Company or any entity that would be
          aggregated with the Company under section 414(b) or (c) of the Code.
          The amount of the Participant's employer-provided benefits under other
          defined benefit plans will be determined as of the Participant's
          Benefit Starting Date. Employer-provided benefits provided to an
          alternate payee under a domestic relations order will be treated as if
          they were provided to the Participant.

                  (c) Third, each monthly installment will be further reduced by
          the monthly amount of a benefit that is the Actuarial Equivalent of
          all employer-provided account balances accumulated on the
          Participant's behalf under any defined contribution plan maintained by
          the Company or any entity that would be aggregated with the Company
          under section 414(b) or (c) of the Code. Employer-provided account
          balances do not include any portion of an account balance attributable
          to salary reduction contributions made by the Participant, regardless
          of whether the contributions are made on a pre-tax or an after-tax
          basis. Account balances will be determined



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          as of 30 days before the Participant's Benefit Starting Date.
          Distributions previously made from the Participant's accounts will be
          taken into account, plus interest from the date of distribution.
          Employer-provided account balances provided to an alternate payee
          under a domestic relations order will be treated as if they were
          provided to the Participant.

                  (d) Fourth, each monthly installment will be further reduced
          by the monthly amount of a benefit that is the Actuarial Equivalent of
          the Participant's Company Contribution Subaccount (within the meaning
          of the JLG Industries, Inc. Executive Deferred Compensation Plan), if
          any, and any investment return (or loss) credited to such subaccount
          pursuant to section 3.3 of such plan. The balance in the Participant's
          subaccount will be determined as of 30 days before the Participant's
          Benefit Starting Date. Previous distributions attributable to the
          Participant's accounts will be taken into account, plus interest from
          the date of distribution.

                   (e) Fifth, after the preceding reductions have been made,
          each monthly installment that is scheduled to be made after the
          Participant reaches Social Security Retirement Age will be further
          reduced by one-half the monthly amount of the federal Social Security
          old-age benefit he is entitled to begin receiving on his Social
          Security Retirement Age.

                  (f) Sixth, after the preceding reductions have been made, the
          resulting monthly installment will be further reduced by multiplying
          it by the Participant's Vested Percentage. The Vested Percentage is
          100 percent in the case of a Participant with 5 or more Years of
          Service, and zero percent in the case of a Participant with less than
          5 Years of Service. A Participant is deemed to have completed 5 Years
          of Service if he dies or becomes Disabled, or if a Change in Control
          occurs, before his Benefit Starting Date.

                  (g) Seventh, after the preceding reductions have been made,
          each monthly installment made during a month for which the Participant
          receives benefits under a long-term disability plan maintained by the
          Company will be further reduced by the amount of the employer-provided
          long-term disability benefit he receives for that month.


SECTION 4. RETIREMENT BENEFITS.

         4.1. NORMAL RETIREMENT BENEFIT. A Participant who retires from service
with the Company on his Normal Retirement Date is entitled to a Normal
Retirement Benefit. Unless he elects otherwise, he will receive his Normal
Retirement Benefit in the form of a Ten-Year Certain Life Annuity beginning on
his Normal Retirement Date. The monthly installments made under his Normal
Retirement Benefit will be the same as the monthly installments under his
Accrued Benefit.

         4.2. LATE RETIREMENT BENEFIT. A Participant who retires from service
with the Company after his Normal Retirement Date is entitled to a Late
Retirement Benefit. Unless he elects otherwise, he will receive his Late
Retirement Benefit in the form of a Ten-Year Certain Life Annuity beginning on
the first day of the month after he retires from service with the Company. The
monthly installments made under his Late Retirement Benefit will be the same as
the monthly installments under his Accrued Benefit (except that the Applicable
Percentage shall be determined taking into account his Years of Service through
his retirement date), beginning with the monthly installment for the month that
includes his Late Retirement Date. However, he will not receive any monthly
installments that would have been made under his Accrued Benefit before his Late
Retirement Date, and no adjustment will be made in his Late Retirement Benefit
to reflect the loss of these installments. For purposes of calculating the Final
Average Compensation of a Participant entitled to a Late Retirement Benefit,
Annual Compensation paid after the Participant's Normal Retirement Date will be
taken into account.


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         4.3. EARLY RETIREMENT BENEFIT. A Participant who retires from service
with the Company on or after age 55 but before his Normal Retirement Date is
entitled to an Early Retirement Benefit. Unless he elects otherwise, he will
receive his Early Retirement Benefit in the form of a Ten-Year Certain Life
Annuity beginning on his Normal Retirement Date. The monthly installments made
under his Early Retirement Benefit will be the same as the monthly installments
under his Accrued Benefit. However, he may elect to begin receiving his Early
Retirement Benefit on the first day of any month before his Normal Retirement
Date and on or after the date he retires from service with the Company.

         4.4. VESTED RETIREMENT BENEFIT. A Participant whose employment with the
Company terminates for any reason before age 55 following a Change in Control is
entitled to a Vested Retirement Benefit. Unless he elects otherwise, he will
receive his Vested Retirement Benefit in the form of a Ten-Year Certain Life
Annuity beginning on his Normal Retirement Date. The monthly installments made
under his Vested Retirement Benefit will be the same as the monthly installments
under his Accrued Benefit. However, he may elect to begin receiving his Vested
Retirement Benefit on the first day of any month before his Normal Retirement
Date and on or after age 55. A Participant whose employment with the Company
terminates for any reason other than death or Disability before age 55 and
before a Change in Control is not entitled to a Retirement Benefit.

         4.5. DISABILITY RETIREMENT BENEFIT. A Participant who becomes Disabled
before his employment with the Company terminates and before he satisfies the
requirements for another Retirement Benefit under this Section 4 is entitled to
a Disability Retirement Benefit. Unless he elects otherwise, he will receive his
Disability Retirement Benefit in the form of a Ten-Year Certain Life Annuity
beginning on his Normal Retirement Date. The monthly installments made under his
Disability Retirement Benefit will be the same as the monthly installments under
his Accrued Benefit. However, he may elect to begin receiving his Disability
Retirement Benefit on the first day of any month before his Normal Retirement
Date and on or after age 55.

         4.6. JOINT & SURVIVOR ANNUITY OPTION. A Participant may elect to
receive his Retirement Benefit in the form of a Ten-Year Certain Joint &
Survivor Annuity rather than a Ten-Year Certain Life Annuity. The Ten-Year
Certain Joint & Survivor Annuity may begin on the first day of any month on
which the Participant is entitled to begin receiving his Retirement Benefit and
will be the Actuarial Equivalent of the Retirement Benefit that would have been
payable to him in the form of a Ten-Year Certain Life Annuity beginning on that
day. Any election under this Section 4.6 must be made before the Participant's
Benefit Starting Date and may not be changed or revoked after that date.

         4.7. LUMP SUM OPTION. Alternatively, a Participant may elect to receive
his Retirement Benefit in the form of a lump sum rather than a Ten-Year Certain
Life Annuity. The lump sum may be paid on the first day of any month on which
the Participant is entitled to begin receiving his Retirement Benefit and will
equal the Actuarial Present Value of the Retirement Benefit that would have been
payable to him in the form of a Ten-Year Certain Life Annuity beginning on that
day. Any election under this Section 4.7 must be made before the Participant's
Benefit Starting Date and may not be changed or revoked after that date.


SECTION 5. PRERETIREMENT DEATH BENEFITS.

         5.1. LUMP SUM BENEFIT. If a Participant dies before his Benefit
Starting Date, his Beneficiary is entitled to a Preretirement Death Benefit,
even if the Participant has not satisfied the requirements for a Retirement
Benefit under Section 4 at the time of his death. Except as provided in Section
5.2, the Preretirement Death Benefit will be paid as soon as administratively
feasible after the Participant's death in



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the form of a lump sum equal to the Actuarial Present Value of the first 120
monthly installments that would have been paid to the Participant under a
Ten-Year Certain Life Annuity that began on the earliest date after his death on
which he could have elected to begin receiving benefits under Section 4, had he
not died.

         5.2. ANNUITY OPTIONS AVAILABLE TO SPOUSE BENEFICIARIES. In lieu of the
lump sum described in Section 5.1, a Beneficiary who is married to the
Participant at the time of his death may elect to receive the Preretirement
Death Benefit in the form of either a Single Life Annuity or a Ten-Year Certain
Fixed Annuity. The Beneficiary may elect to begin receiving the Single Life
Annuity or Ten-Year Certain Fixed Annuity on any date after the Participant's
death on which the Participant could have elected to begin receiving benefits
under Section 4, had he not died. Any election under this Section 5.2 must be
made before the Beneficiary's Benefit Starting Date and may not be changed or
revoked after that date.


SECTION 6. NATURE OF PARTICIPANT'S INTEREST IN PLAN.

         6.1. NO RIGHT TO ASSETS. Participation in the Plan does not create, in
favor of any Participant or Beneficiary, any right or lien in or against any
asset of the Company. Nothing contained in the Plan, and no action taken under
its provisions, will create or be construed to create a trust of any kind, or a
fiduciary relationship, between the Company and a Participant or any other
person. The Company's promise to pay benefits under the Plan will at all times
remain unfunded as to each Participant and Beneficiary, whose rights under the
Plan are limited to those of a general and unsecured creditor of the Company.

         6.2. NO RIGHT TO TRANSFER INTEREST. Rights to benefits payable under
the Plan are not subject in any manner to anticipation, alienation, sale,
transfer, assignment, pledge, or encumbrance. However, the Administrative
Committee may permit a Participant or Beneficiary to enter into a revocable
arrangement to pay all or part of his benefits under the Plan to a revocable
grantor trust (a so-called "living trust"). In addition, the Administrative
Committee may recognize the right of an alternate payee named in a domestic
relations order to receive all or part of a Participant's benefits under the
Plan, but only if (a) the domestic relations order would be a "qualified
domestic relations order" within the meaning of section 414(p) of the Code (if
section 414(p) applied to the Plan), (b) the domestic relations order does not
attempt to give the alternate payee any right to any asset of the Company, (c)
the domestic relations order does not attempt to give the alternate payee any
right to receive payments under the Plan at a time or in an amount that the
Participant could not receive under the Plan, and (d) the amount of the
Participant's benefits under the Plan are reduced to reflect any payments made
or due the alternate payee.

         6.3. NO EMPLOYMENT RIGHTS. No provisions of the Plan and no action
taken by the Company, the Board of Directors, the Compensation Committee, or the
Administrative Committee will give any person any right to be retained in the
employ of the Company, and the Company specifically reserves the right and power
to dismiss or discharge any Participant.

         6.4. WITHHOLDING AND TAX LIABILITIES. The amount of any withholdings
required to be made by any government or government agency will be deducted from
benefits paid under the Plan to the extent deemed necessary by the
Administrative Committee. In addition, the Participant or Beneficiary (as the
case may be) will bear the cost of any taxes not withheld on benefits provided
under the Plan, regardless of whether withholding is required.


SECTION 7. ADMINISTRATION, INTERPRETATION, AND MODIFICATION OF PLAN.

         7.1. PLAN ADMINISTRATOR. The Administrative Committee will administer
the Plan.


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         7.2. POWERS OF COMMITTEE. The Administrative Committee's powers
include, but are not limited to, the power to adopt rules consistent with the
Plan; the power to decide all questions relating to the interpretation of the
terms and provisions of the Plan; and the power to resolve all other questions
arising under the Plan (including, without limitation, the power to remedy
possible ambiguities, inconsistencies, or omissions by a general rule or
particular decision). The Administrative Committee has discretionary authority
to exercise each of the foregoing powers.

         7.3. FINALITY OF COMMITTEE DETERMINATIONS. Determinations by the
Administrative Committee and any interpretation, rule, or decision adopted by
the Administrative Committee under the Plan or in carrying out or administering
the Plan will be final and binding for all purposes and upon all interested
persons, their heirs, and their personal representatives.

         7.4. INCAPACITY. If the Administrative Committee determines that any
person entitled to benefits under the Plan is unable to care for his affairs
because of illness or accident, any payment due (unless a duly qualified
guardian or other legal representative has been appointed) may be paid for the
benefit of such person to his spouse, parent, brother, sister, or other party
deemed by the Administrative Committee to have incurred expenses for such
person.

         7.5. AMENDMENT, SUSPENSION, AND TERMINATION. The Board of Directors has
the right by written resolution to amend, suspend, or terminate the Plan at any
time. However, no amendment, suspension, or termination will apply to an
employee who already is a Participant in the Plan without his express written
consent.

         7.6. POWER TO DELEGATE BOARD AUTHORITY. The Board of Directors may, in
its sole discretion, delegate to any person or persons all or part of its
authority and responsibility under the Plan, including, without limitation, the
authority to amend the Plan.

         7.7. HEADINGS. The headings used in this document are for convenience
of reference only and may not be given any weight in interpreting any provision
of the Plan.

         7.8. SEVERABILITY. If any provision of the Plan is held illegal or
invalid for any reason, the illegality or invalidity of that provision will not
affect the remaining provisions of the Plan, and the Plan will be construed and
enforced as if the illegal or invalid provision had never been included in the
Plan.

         7.9. GOVERNING LAW. The Plan will be construed, administered, and
regulated in accordance with the laws of the Commonwealth of Pennsylvania,
except to the extent that those laws are preempted by federal law.

         7.10. COMPLETE STATEMENT OF PLAN. This Plan supersedes the Prior Plan
with respect to the Participants. This Plan contains a complete statement of its
terms. The Plan may be amended, suspended, or terminated only in writing and
then only as provided in Section 7.5. A Participant's right to any benefit of a
type provided under the Plan will be determined solely in accordance with the
terms of the Plan. No other evidence, whether written or oral, will be taken
into account in interpreting the provisions of the Plan. Notwithstanding the
preceding provisions of this Section 7.10, for purposes of determining benefits
with respect to a Participant, this Plan will be deemed to include (a) the
provisions of the written agreement between the Company and the Participant
executed in accordance with Section 2.3, and (b) the provisions of any other
written agreement between the Company and the Participant to the extent such
other agreement explicitly provides for the incorporation of some or all of its
terms into this Plan.


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SECTION 8. TERMS USED IN THE PLAN.

         8.1. GENDER AND NUMBER. Words used in the masculine gender in the Plan
are intended to include the feminine and neuter genders, where appropriate.
Words used in the singular form in the Plan are intended to include the plural
form, where appropriate, and vice versa.

         8.2. DEFINITIONS. When used in capitalized form in the Plan, the
following words and phrases have the following meanings, unless the context
clearly indicates that a different meaning is intended:

                  "ACCRUED BENEFIT" means the benefit described in Section 3 or
          Appendix A, whichever is applicable.

                  "ACTUARIAL EQUIVALENT" means the following: an amount or
          benefit is the "Actuarial Equivalent" of, or is "Actuarially
          Equivalent" to, another amount or benefit as of a specified date, if
          the Actuarial Present Value as of the specified date of the first
          amount or benefit equals the Actuarial Present Value as of the
          specified date of the second amount or benefit, when calculated using
          the same actuarial assumptions. Actuarial Equivalence under Section
          3.4 will be determined as of the Participant's Benefit Starting Date,
          and the resulting benefit will be expressed in the form of a Ten-Year
          Certain Life Annuity beginning on the Participant's Benefit Starting
          Date. Actuarial Equivalence under Section 4.6 will be determined as of
          the Participant's Benefit Starting Date, and the resulting benefit
          will be expressed in the form of a Ten-Year Certain Joint & Survivor
          Annuity beginning on the Participant's Benefit Starting Date.
          Actuarial Equivalence under the definition of "Single Life Annuity" in
          this Section 8.2 will be determined as of the Beneficiary's Benefit
          Starting Date, and the resulting benefit will be expressed in the form
          of a Single Life Annuity beginning on the Beneficiary's Benefit
          Starting Date.

                  "ACTUARIAL PRESENT VALUE" means the value as of a specified
          date of an amount or a series of amounts due before or thereafter,
          where each amount is multiplied by the probability that the condition
          or conditions on which payment of the amount is contingent will be
          satisfied, and where each amount so multiplied is then increased (if
          due before) or discounted (if due thereafter) according to an assumed
          rate of interest to reflect the time value of money. Unless the Plan
          specifies otherwise, the mortality table and interest rate used to
          calculate the Actuarial Present Value of an amount or series of
          amounts will be the mortality table and interest rate in effect under
          section 417(e)(3)(A)(ii) of the Code 90 days before the Participant's
          Benefit Starting Date.

                  "ADMINISTRATIVE COMMITTEE" means the Administrative Committee
          appointed to administer the JLG Industries, Inc. Employees' Retirement
          Savings Plan. However, following a Change in Control, "Administrative
          Committee" means the trustee under the grantor trust maintained by the
          Company in connection with the Plan.

                  "ANNUAL COMPENSATION" has the meaning assigned to that term in
          Section 3.3 or Appendix A, whichever is applicable.

                  "APPLICABLE PERCENTAGE" has the meaning assigned to that term
          in Section 3.2 or Appendix A, whichever is applicable.

                  "ASSOCIATE" has the meaning assigned to that term for purposes
          of Rule 12b-2 of the General Rules and Regulations under the
          Securities Exchange Act.


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                  "BENEFICIAL OWNER" means the following: a Person is deemed to
          be the "Beneficial Owner" of, to "Beneficially Own," and to have
          "Beneficial Ownership" of, any securities:

                           (1) which such Person or any of such Person's
                  Securities Law Affiliates or Associates beneficially owns,
                  directly or indirectly;

                           (2) which such Person or any of such Person's
                  Securities Law Affiliates or Associates has (A) the right or
                  obligation to acquire (whether such right or obligation is
                  exercisable or effective immediately or only after the passage
                  of time) pursuant to any agreement, arrangement, or
                  understanding (whether or not in writing) or upon the exercise
                  of conversion rights, exchange rights, rights, warrants or
                  options, or otherwise; provided that a Person shall not be
                  deemed the "Beneficial Owner" of, or to "Beneficially Own," or
                  to have "Beneficial Ownership" of, securities tendered
                  pursuant to a tender or exchange offer made by such Person or
                  any of such Person's Securities Law Affiliates or Associates
                  until such tendered securities are accepted for purchase or
                  exchange; or (B) the right to vote pursuant to any agreement,
                  arrangement, or understanding (whether or not in writing);
                  provided that a Person shall not be deemed the "Beneficial
                  Owner" of, or to "Beneficially Own," or to have "Beneficial
                  Ownership" of, any security under this clause (B) if the
                  agreement, arrangement, or understanding to vote such security
                  (i) arises solely from a revocable proxy given in response to
                  a public proxy or consent solicitation made pursuant to, and
                  in accordance with, the applicable rules and regulations of
                  the Securities Exchange Act, and (ii) is not also then
                  reported by such Person on Schedule 13D under the Securities
                  Exchange Act (or any comparable or successor report); or

                           (3) which are beneficially owned, directly or
                  indirectly, by any other Person (or any Securities Law
                  Affiliate or Associate thereof) with which such Person or any
                  of such Person's Securities Law Affiliates or Associates has
                  any agreement, arrangement, or understanding (whether or not
                  in writing) or with which such Person or any of such Person's
                  Securities Law Affiliates have otherwise formed a group for
                  the purpose of acquiring, holding, voting (except pursuant to
                  a revocable proxy as described in clause (B)(i) of paragraph
                  (2), above), or disposing of any securities of the Company.

                  "BENEFICIARY" means the person designated in writing by a
          Participant to receive benefits under the Plan after the Participant's
          death. If a Participant dies before his Benefit Starting Date and he
          has failed to designate a Beneficiary or his designated Beneficiary
          fails to survive him, his Beneficiary will be the person to whom he is
          married at the time of his death, or if he is not married at that
          time, his Beneficiary will be the executor of his will or the
          administrator of his estate. If a Participant who has elected a
          Ten-Year Certain Life Annuity dies on or after his Benefit Starting
          Date and he has failed to designate a Beneficiary or his Beneficiary
          fails to survive him, his Beneficiary will be the person to whom he is
          married at the time of his death, or if he is not married at that
          time, the Actuarial Present Value of the payments (if any) to be made
          after his death will be paid in an immediate lump sum to the executor
          of his will or the administrator of his estate. A Participant may
          revoke in writing a prior designation of a Beneficiary at any time
          before the earlier of the Participant's death or his Benefit Starting
          Date. In addition, a Participant may revoke in writing a prior
          designation of a Beneficiary under a Ten-Year Certain Life Annuity at
          any time before the Participant's death. A Beneficiary under a
          Ten-Year Certain Life Annuity or a Ten-Year Certain Fixed Annuity may
          designate in writing a person to receive any benefits due under the
          Plan after the Beneficiary's death (a "Beneficiary's Beneficiary").
          The Beneficiary may revoke this designation in writing at any time
          before his death.


                                       8
<PAGE>   12

                  "BENEFIT STARTING DATE" means the date on which a Participant
          or Beneficiary is scheduled to begin receiving benefits under the
          Plan.

                  "BOARD OF DIRECTORS" means the Board of Directors of the
          Company.

                  "CHANGE IN CONTROL" means the first to occur of the following
          events:

                           (1) an acquisition (other than directly from the
                  Company) of securities of the Company by any Person,
                  immediately after which such Person, together with all
                  Securities Law Affiliates and Associates of such Person,
                  becomes the Beneficial Owner of securities of the Company
                  representing 25 percent or more of the Voting Power; provided
                  that, in determining whether a Change in Control has occurred,
                  the acquisition of securities of the Company in a Non-Control
                  Acquisition will not constitute an acquisition that would
                  cause a Change in Control; or

                           (2) three or more directors, whose election or
                  nomination for election is not approved by a majority of the
                  members of the Incumbent Board then serving as members of the
                  Board of Directors, are elected within any single 12-month
                  period to serve on the Board of Directors; provided that an
                  individual whose election or nomination for election is
                  approved as a result of either an actual or threatened
                  Election Contest or Proxy Contest, including by reason of any
                  agreement intended to avoid or settle any Election Contest or
                  Proxy Contest, will be deemed not to have been approved by a
                  majority of the Incumbent Board for purposes of this
                  definition; or

                           (3) members of the Incumbent Board cease for any
                  reason to constitute at least a majority of the Board of
                  Directors; or

                           (4) approval by shareholders of the Company of:

                                    (A) a merger, consolidation, or
                           reorganization involving the Company, unless

                                             (i) the shareholders of the
                                    Company, immediately before the merger,
                                    consolidation, or reorganization, own,
                                    directly or indirectly immediately following
                                    such merger, consolidation, or
                                    reorganization, at least 75 percent of the
                                    combined voting power of the outstanding
                                    voting securities of the corporation
                                    resulting from such merger, consolidation,
                                    or reorganization in substantially the same
                                    proportion as their ownership of the voting
                                    securities immediately before such merger,
                                    consolidation, or reorganization;

                                             (ii) individuals who were members
                                    of the Incumbent Board immediately prior to
                                    the execution of the agreement providing for
                                    such merger, consolidation, or
                                    reorganization constitute at least a
                                    majority of the board of directors of the
                                    Surviving Corporation; and

                                             (iii) no Person (other than (1) the
                                    Company or any Subsidiary thereof, (2) any
                                    employee benefit plan (or any trust forming
                                    a part thereof) maintained by the Company,
                                    any Subsidiary thereof, or the Surviving
                                    Corporation, or (3) any Person who,
                                    immediately prior to such


                                       9
<PAGE>   13


                                    merger, consolidation, or reorganization,
                                    had Beneficial Ownership of securities
                                    representing 25 percent or more of the
                                    Voting Power) has Beneficial Ownership of
                                    securities representing 25 percent or more
                                    of the combined voting power of the
                                    Surviving Corporation's then outstanding
                                    voting securities;

                                    (B) a complete liquidation or dissolution of
                           the Company; or

                                    (C) an agreement for the sale or other
                           disposition of all or substantially all of the assets
                           of the Company to any Person (other than a transfer
                           to a Subsidiary of the Company).

                  "CODE" means the Internal Revenue Code of 1986, as amended and
          in effect from time to time.

                  "COMPANY" means JLG Industries, Inc., and any successor to JLG
          Industries, Inc. Employment with the Company includes employment with
          any corporation, partnership, or other organization required to be
          aggregated with the Company under sections 414(b) and (c) of the Code.

                  "COMPENSATION COMMITTEE" means the Compensation Committee of
          the Board of Directors.

                  "DISABILITY RETIREMENT BENEFIT" means the benefit described in
          Section 4.5.

                  "DISABLED" means entitled to receive benefits under a
          long-term disability plan maintained by the Company.

                  "EARLY RETIREMENT BENEFIT" means the benefit described in
          Section 4.3.

                  "EFFECTIVE DATE" means June 1, 1995.

                  "ELECTION CONTEST" means an election contest described in Rule
          14a-11 promulgated under the Securities Exchange Act.

                  "ELIGIBLE EXECUTIVE" means an employee of the Company who is
          an officer of the Company or who holds any other key position
          designated by the Compensation Committee in its sole discretion.

                  "FINAL AVERAGE COMPENSATION" has the meaning assigned to that
          term in Section 3.3 or Appendix A, whichever is applicable.

                  "INCUMBENT BOARD" means individuals who, as of the close of
          business on the Effective Date, are members of the Board of Directors;
          provided that, if the election, or nomination for election by the
          Company's shareholders, of any new director was approved by a vote of
          at least 75 percent of the Incumbent Board, such new director shall,
          for purposes of the Plan, be considered as a member of the Incumbent
          Board; provided further that no individual shall be considered a
          member of the Incumbent Board if such individual initially assumed
          office as a result of either an actual or threatened Election Contest
          or other actual or threatened Proxy Contest, including by reason of
          any agreement intended to avoid or settle any Election Contest or
          Proxy Contest.


                                       10
<PAGE>   14

                  "LATE RETIREMENT BENEFIT" means the benefit described in
          Section 4.2.

                  "LATE RETIREMENT DATE" means the first day of the month
          following the month in which a Participant retires from service with
          the Company, if he retires from service with the Company after his
          Normal Retirement Date.

                  "NON-CONTROL ACQUISITION" means an acquisition by (1) an
          employee benefit plan (or a trust forming a part thereof) maintained
          by (A) the Company or (B) any of its Subsidiaries, (2) the Company or
          any of its Subsidiaries, or (3) any Person in connection with a
          Non-Control Transaction.

                  "NON-CONTROL TRANSACTION" means any transaction described in
          clauses (4)(A)(i) through (iii) of the definition of "Change in
          Control."

                  "NORMAL RETIREMENT BENEFIT" means the benefit described in
          Section 4.1.

                  "NORMAL RETIREMENT DATE" means the first day of the month
          following the month in which a Participant reaches age 62, unless a
          Change in Control occurs, in which case Normal Retirement Date means
          the first day of the month following the month in which the
          Participant reaches age 60. In the case of a Participant who dies
          before reaching his Normal Retirement Date, Normal Retirement Date
          means the day on which the Participant would have reached his Normal
          Retirement Date had he not died.

                  "PARTICIPANT" means a member of a select group of management
          or highly compensated employees of the Company who has become a
          participant in the Plan under Section 2.

                  "PERSON" means any individual, firm, corporation, partnership,
          joint venture, association, trust, or other entity.

                  "PLAN" means the JLG Industries, Inc. Supplemental Executive
          Retirement Plan as set forth in this document.

                  "PRERETIREMENT DEATH BENEFIT" means the benefit described in
          Section 5.1.

                  "PRIOR PLAN" means an individual agreement (customarily
          denominated a "Deferred Compensation Benefit Agreement") between the
          Company and the employee that provides for unfunded deferred
          compensation benefits and certain other benefits specified in the
          agreement.

                  "PROXY CONTEST" means a solicitation of proxies or consents by
          or on behalf of a Person other than the Board of Directors.

                  "RETIREMENT BENEFIT" means a Normal Retirement Benefit, a Late
          Retirement Benefit, an Early Retirement Benefit, a Vested Retirement
          Benefit, or a Disability Retirement Benefit.

                  "SECTION" means a section of this Plan. For example, a
          reference to Section 2 includes a reference to Sections 2.1 through
          2.3, while a reference to Section 2.1 is intended as a reference to
          Section 2.1 only.

                  "SECURITIES EXCHANGE ACT" means the Securities Exchange Act of
          1934, as amended and in effect from time to time.


                                       11
<PAGE>   15

                  "SECURITIES LAW AFFILIATE" means an "affiliate" as defined for
          purposes of Rule 12b-2 of the General Rules and Regulations under the
          Securities Exchange Act.

                  "SINGLE LIFE ANNUITY" means an annuity payable in equal
          monthly installments to a Beneficiary, beginning with the calendar
          month in which the Beneficiary's Benefit Starting Date occurs and
          ending with the calendar month in which the Beneficiary dies. The
          Single Life Annuity payable to a Beneficiary will be the Actuarial
          Equivalent of the Preretirement Death Benefit that the Beneficiary
          could have elected to receive in the form of a Ten-Year Certain Fixed
          Annuity beginning on the same day.

                  "SOCIAL SECURITY RETIREMENT AGE" means the earliest age at
          which the Participant is entitled to begin receiving federal Social
          Security old-age benefits. In the case of a Participant who dies
          before reaching his Social Security Retirement Date, Social Security
          Retirement Date means the day on which the Participant would have
          reached his Social Security Retirement Date had he not died.

                  "SUBSIDIARY" of any Person means any corporation or other
          entity of which at least 80 percent (or such lesser percentage as the
          Administrative Committee may determine) of the voting power of the
          voting equity securities or voting interest therein is owned, directly
          or indirectly, by such Person.

                  "SURVIVING CORPORATION" means a corporation resulting from a
          merger, consolidation, or reorganization described in paragraph
          (4)(A)(i) of the definition of "Change in Control."

                  "TEN-YEAR CERTAIN FIXED ANNUITY" means an annuity payable in
          120 monthly installments that are equal to the first 120 monthly
          installments that would have been paid to the Participant (had he not
          died) under a Ten-Year Certain Life Annuity that began on the
          Beneficiary's Benefit Starting Date. The 120 monthly installments will
          be paid to the Beneficiary unless the Beneficiary dies before all 120
          monthly installments have been paid, in which case the Actuarial
          Present Value of the remaining installments will be paid to the
          Beneficiary's Beneficiary in an immediate lump sum.

                  "TEN-YEAR CERTAIN JOINT & SURVIVOR ANNUITY" means an annuity
          payable in equal monthly installments to the Participant, beginning
          with the calendar month in which his Benefit Starting Date occurs and
          ending with the calendar month in which he dies, and thereafter in
          equal monthly installments of the same or a lesser amount to his
          surviving Beneficiary (if any), beginning with the calendar month
          following the calendar month in which he dies and ending with the
          calendar month in which the Beneficiary dies, provided that if the
          Participant and his Beneficiary both die before the end of the
          120-month period that begins on the Participant's Benefit Starting
          Date, the Actuarial Present Value of the additional monthly
          installments that would have been paid to the last to survive of the
          Participant and his Beneficiary (had the last survivor not died until
          the end of the 120-month period) will be paid in an immediate lump sum
          to the executor of the last survivor's will or the administrator of
          the last survivor's estate. At the time he elects a Ten-Year Certain
          Joint & Survivor Annuity, the Participant must designate a named
          natural person as his Beneficiary and must specify whether the monthly
          amount payable to the Beneficiary will be 50 or 100 percent of the
          monthly amount payable to him under the Ten-Year Certain Joint &
          Survivor Annuity. After his Benefit Starting Date, the terms of his
          election may not be changed or revoked.

                  "TEN-YEAR CERTAIN LIFE ANNUITY" means an annuity payable in
          monthly installments to the Participant, beginning with the calendar
          month in which his Benefit Starting Date occurs and ending



                                       12
<PAGE>   16

          with the calendar month in which he dies, provided that if he dies
          before the end of the 120-month period that begins on his Benefit
          Starting Date, the monthly installments will be continued to his
          Beneficiary, beginning with the calendar month following the calendar
          month in which the Participant dies and ending with the calendar month
          in which the 120-month period ends. Except as required under Section
          3.4(e) and (f), the monthly installments payable under a Ten-Year
          Certain Life Annuity will be equal in amount.

                  "YEAR OF SERVICE" has the meaning assigned to that term under
          the JLG Industries, Inc. Employees' Retirement Savings Plan. To the
          extent the Company awards any additional service credit under the JLG
          Industries, Inc. Employees' Retirement Savings Plan beyond the service
          required to be credited for vesting purposes under the savings plan,
          the additional service shall count as Years of Service under this Plan
          only to the extent expressly provided in a written resolution of the
          Board of Directors.

                  "VESTED RETIREMENT BENEFIT" means the benefit described in
          Section 4.4.

                  "VOTING POWER" means the voting power of all securities of the
          Company then outstanding generally entitled to vote for the election
          of directors of the Company.


                                           JLG INDUSTRIES, INC.

ATTEST:                                    BY:
       ----------------------------            --------------------------------

TITLE:                                     TITLE:
      -----------------------------               -----------------------------


                                       13
<PAGE>   17



                                   APPENDIX A
            ACCRUED BENEFIT OF PARTICIPANTS BEFORE SEPTEMBER 6, 2000

         A.1. INTRODUCTION. The Plan was amended effective September 6, 2000, to
change the formula for determining the Accrued Benefit of individuals who first
became Participants on or after September 6, 2000. The Accrued Benefit of
individuals who first became Participants before September 6, 2000 ("Prior
Participants") continues to be determined under the formula in effect before the
amendment. This Appendix A describes the method of determining the Accrued
Benefit of Prior Participants. Except as provided in Appendix A, Prior
Participants remain subject to the regular provisions of the Plan, as amended
from time to time.

         A.2. DEFINITIONS. A Prior Participant's Accrued Benefit under the Plan
is a monthly benefit equal to the Applicable Percentage of his Final Average
Compensation, payable in the form of a Ten-Year Certain Life Annuity beginning
on his Normal Retirement Date, and reduced in accordance with Section A.5.
Actuarial Equivalence under Section A.5 will be determined as of the Prior
Participant's Normal Retirement Date, and the resulting benefit will be
expressed in the form of a Ten-Year Certain Life Annuity beginning on the Prior
Participant's Normal Retirement Date.

         A.3. APPLICABLE PERCENTAGE. A Prior Participant's Applicable Percentage
is the percentage specified by the Compensation Committee with respect to the
Prior Participant for purposes of the Plan and reflected in the written
agreement between the Company and the Prior Participant executed in accordance
with Section 2.3.

         A.4. FINAL AVERAGE COMPENSATION. A Prior Participant's Final Average
Compensation is one-twelfth the average of his Annual Compensation for the 2
consecutive or nonconsecutive calendar years during which the average of his
Annual Compensation is the highest. The Annual Compensation of a Prior
Participant for a calendar year is the amount of the Prior Participant's base
salary for the calendar year and the amount of any cash bonus paid to him in the
calendar year, each including (i) amounts that are contributed, at the election
of a Prior Participant, on behalf of the Prior Participant to a cafeteria plan
or a cash or deferred arrangement and not included in the Prior Participant's
gross income for federal income tax purposes by reason of section 125 or
402(e)(3) of the Code and (ii) compensation deferred under the JLG Industries,
Inc. Executive Deferred Compensation Plan (or any successor thereto). Annual
Compensation earned more than 10 years before the year in which the Prior
Participant's employment with the Company terminates is ignored. Annual
Compensation does not include any amount realized as a result of the grant,
modification, or exercise of a stock option.

         A.5. REQUIRED REDUCTIONS. The monthly installments otherwise included
in a Prior Participant's Accrued Benefit will be reduced as follows:

                  (a) First, each monthly installment will be reduced by the
         monthly amount of a benefit that is the Actuarial Equivalent of all
         employer-provided benefits the Prior Participant has received, is
         receiving, or is expected to receive under any defined benefit plan
         (other than this Plan), regardless of whether the defined benefit plan
         is maintained by the Company or another employer, including an
         unrelated employer. Employer-provided benefits provided to an alternate
         payee under a domestic relations order will be treated as if they were
         provided to the Prior Participant.

                  (b) Second, each monthly installment will be further reduced
         by the monthly amount of a benefit that is the Actuarial Equivalent of
         all employer-provided account balances accumulated on the Prior
         Participant's behalf under any defined contribution plan, regardless of
         whether the defined contribution plan is maintained by the Company or
         another employer, including an unrelated


                                       A-1
<PAGE>   18


         employer. Employer-provided account balances do not include any portion
         of an account balance attributable to salary reduction contributions
         made by the Prior Participant, regardless of whether the contributions
         are made on a pre-tax or an after-tax basis. Account balances will be
         determined as of 30 days before the Prior Participant's Benefit
         Starting Date. Distributions previously made from the Prior
         Participant's accounts will be taken into account, plus interest from
         the date of distribution. Employer-provided account balances provided
         to an alternate payee under a domestic relations order will be treated
         as if they were provided to the Prior Participant.

                  (c) Third, each monthly installment will be further reduced by
         the monthly amount of a benefit that is the Actuarial Equivalent of the
         Prior Participant's Company Contribution Subaccount (within the meaning
         of the JLG Industries, Inc. Executive Deferred Compensation Plan), if
         any, and any investment return (or loss) credited to such subaccount
         pursuant to section 3.3 of such plan. The balance in the Prior
         Participant's subaccount will be determined as of 30 days before the
         Prior Participant's Benefit Starting Date. Previous distributions
         attributable to the Prior Participant's accounts will be taken into
         account, plus interest from the date of distribution.

                  (d) Fourth, after the preceding reductions have been made,
         each monthly installment that is scheduled to be made after the Prior
         Participant reaches Social Security Retirement Age will be further
         reduced by one-half the monthly amount of the federal Social Security
         old-age benefit he is entitled to begin receiving on his Social
         Security Retirement Age.

                  (e) Fifth, if the Prior Participant elects to begin receiving
         benefits before his Normal Retirement Date, the monthly installment
         resulting after the preceding reductions have been made will be further
         reduced by one-half of one percent for each month during which benefits
         are scheduled to be paid before his Normal Retirement Date.

                  (f) Sixth, after the preceding reductions have been made, the
         resulting monthly installment will be further reduced by multiplying it
         by the Prior Participant's Vested Percentage. The Vested Percentage is
         100 percent in the case of a Prior Participant with 5 or more Years of
         Service, 75 percent in the case of a Prior Participant with 4 but less
         than 5 Years of Service, 50 percent in the case of a Prior Participant
         with 3 but less than 4 Years of Service, 25 percent in the case of a
         Prior Participant with 2 but less than 3 Years of Service, and zero
         percent in the case of a Prior Participant with less than 2 Years of
         Service. A Prior Participant is deemed to have completed 5 Years of
         Service if he dies or becomes Disabled, or if a Change in Control
         occurs, before his Benefit Starting Date.

                  (g) Seventh, after the preceding reductions have been made,
         each monthly installment made during a month for which the Prior
         Participant receives benefits under a long-term disability plan
         maintained by the Company will be further reduced by the amount of the
         employer-provided long-term disability benefit he receives for that
         month.


                                      A-2