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                                                                    EXHIBIT 10.4

                           [FIRST NATIONAL BANK LOGO]

                              COMMERCIAL GUARANTY


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<S>        <C>                                                 <C>
BORROWER:  Agricultural Supply, Inc., a Delaware corporation   Lender:  First National Bank
           10740 Thornmint                                              401 West A Street
           San Diego, CA 92127                                          P.O. Box 85625
                                                                        San Diego, CA 92101

GUARANTOR: Max Gelwix
           William B. Adams
           15751 El Camino Entrada
           Poway, CA 92064
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AMOUNT OF GUARANTY.  THE PRINCIPAL AMOUNT OF THIS GUARANTY IS TWO MILLION &
00/100 DOLLARS ($2,000,000.00).

CONTINUING GUARANTY.  FOR GOOD AND VALUABLE CONSIDERATION, MAX GELWIX AND
WILLIAM B. ADAMS ("GUARANTOR") ABSOLUTELY AND UNCONDITIONALLY GUARANTEES AND
PROMISES TO PAY, JOINTLY AND SEVERALLY, TO FIRST NATIONAL BANK ("LENDER") OR
ITS ORDER, IN LEGAL TENDER OF THE UNITED STATES OF AMERICA, THE INDEBTEDNESS
(AS THAT TERM IS DEFINED BELOW) OF AGRICULTURAL SUPPLY, INC., A DELAWARE
CORPORATION ("BORROWER") TO LENDER ON THE TERMS AND CONDITIONS SET FORTH IN
THIS GUARANTY. THE OBLIGATIONS OF GUARANTOR UNDER THIS GUARANTY ARE CONTINUING.

MAXIMUM LIABILITY.  The maximum liability of Guarantor under this Guaranty
shall not exceed at any one time the sum of the principal amount of
$2,000,000.00, plus all interest thereon, plus all of Lender's costs, expenses,
and attorneys' fees incurred in connection with or relating to (A) the
collection of the Indebtedness, (B) the collection and sale of any collateral
for the Indebtedness or this Guaranty, or (C) the enforcement of this Guaranty.
Attorneys' fees include, without limitation, attorneys' fees whether or not
there is a lawsuit, and if there is a lawsuit, any fees and costs for trial and
appeals.

The above limitation on liability is not a restriction on the amount of the
Indebtedness of Borrower to Lender either in the aggregate or at any one time.
If Lender presently holds one or more guaranties, or hereafter receives
additional guaranties from Guarantor, Lender's rights under all guaranties
shall be cumulative. This Guaranty shall not (unless specifically provided
below to the contrary) affect or invalidate any such other guaranties.
Guarantor's liability will be Guarantor's aggregate liability under the terms
of this Guaranty and any such other unterminated guaranties.

INDEBTEDNESS GUARANTEED.  The Indebtedness guaranteed by this Guaranty includes
any and all of Borrower indebtedness to Lender and is used in the most
comprehensive sense and means and includes any and all of Borrower's
liabilities, obligations and debts to Lender, now existing or hereinafter
incurred or created, including, without limitation, all loans, advances,
interest, costs, debts, overdraft indebtedness, credit card indebtedness, lease
obligations, other obligations, and liabilities of Borrower, or any of them, and
any present or future judgments against Borrower, or any of them; and whether
any such indebtedness is voluntarily or involuntarily incurred, due or not due,
absolute or contingent, liquidated or unliquidated, determined or undetermined;
whether Borrower may be liable individually or jointly with others, or primarily
or secondarily, or as guarantor or surety; whether recovery on the indebtedness
may be or may become barred or unenforceable against Borrower for any reason
whatsoever; and whether the Indebtedness arises from transactions which may be
voidable on account of infancy, insanity, ultra vires, or otherwise.

DURATION OF GUARANTY.  This Guaranty will take effect when received by Lender
without the necessity of any acceptance by Lender, or any notice to Guarantor
or to Borrower, and will continue in full force until all Indebtedness incurred
or contracted before receipt by Lender of any notice of revocation shall have
been fully and finally paid and satisfied and all of Guarantor's other
obligations under this Guaranty shall have been performed in full. If Guarantor
elects to revoke this Guaranty, Guarantor may only do so in writing.
Guarantor's written notice of revocation must be mailed to Lender, by certified
mail, at Lender's address listed above or such other place as Lender may
designate in writing. Written revocation must be mailed to Lender, by certified
mail, at Lender's address listed above or such other place as Lender may
designate in writing. Written revocation of this Guaranty will apply only to
advances or new Indebtedness created after actual receipt by Lender of
Guarantor's written revocation. For this purpose and without limitation, the
term "new Indebtedness" does not include Indebtedness which at the time of
notice of revocation is contingent, unliquidated, undetermined or not due and
which later becomes absolute, liquidated, determined or due. This Guaranty will
continue to bind Guarantor for all Indebtedness incurred by Borrower or
committed by Lender prior to receipt of Guarantor's written notice of
revocation, including any extensions, renewals, substitutions or modifications
of the Indebtedness. All renewals, extensions, substitutions, and modifications
of the Indebtedness granted after Guarantor's revocation, are contemplated
under this Guaranty and, specifically will not be considered to be new
Indebtedness. This Guaranty shall bind Guarantor's estate as to Indebtedness
created both before and after Guarantor's death or incapacity, regardless of
Lender's actual notice of Guarantor's death. Subject to the foregoing,
Guarantor's executor or administrator or other legal representative may
terminate this Guaranty in the same manner in which Guarantor might have
terminated it and with the same effect. Release of any other guarantor or
termination of any other guaranty of the Indebtedness shall not affect the
liability of Guarantor under this Guaranty. A revocation Lender receives from
any one or more Guarantors shall not affect the liability of any remaining
Guarantors under this Guaranty. IT IS ANTICIPATED THAT FLUCTUATIONS MAY OCCUR
IN THE AGGREGATE AMOUNT OF INDEBTEDNESS COVERED BY THIS GUARANTY, AND GUARANTOR
SPECIFICALLY ACKNOWLEDGES AND AGREES THAT REDUCTIONS IN THE AMOUNT OF
INDEBTEDNESS, EVEN TO ZERO DOLLARS ($0.00), PRIOR TO GUARANTOR'S WRITTEN
REVOCATION OF THIS GUARANTY SHALL NOT CONSTITUTE A TERMINATION OF THIS
GUARANTY. THIS GUARANTY IS BINDING UPON GUARANTOR AND GUARANTOR'S HEIRS,
SUCCESSORS AND ASSIGNS SO LONG AS ANY OF THE GUARANTEED INDEBTEDNESS REMAINS
UNPAID AND EVEN THOUGH THE INDEBTEDNESS GUARANTEED MAY FROM TIME TO TIME BE
ZERO DOLLARS ($0.00).

OBLIGATIONS OF MARRIED PERSONS.  Any married person who signs this Guaranty
hereby expressly agrees that this Guaranty binds the marital and community
property and the sole and separate property of Max Gelwix, but not the sole and
separate property of William B. Adams.

GUARANTOR'S AUTHORIZATION TO LENDER.  Guarantor authorizes Lender, either before
or after any revocation hereof, WITHOUT NOTICE OR DEMAND AND WITHOUT LESSENING
GUARANTOR'S LIABILITY UNDER THIS GUARANTY, FROM TIME TO TIME: (A) prior to
revocation as set forth above, to make one or more additional secured or
unsecured loans to Borrower, to lease equipment or other goods to Borrower, or
otherwise to extend additional credit to Borrower; (B) to alter, compromise,
renew, extend, accelerate, or otherwise change one or more times the time for
payment or other terms of the Indebtedness or any part of the Indebtedness,
including increases and decreases of the rate of interest on the Indebtedness;
extensions may be repeated and may be for longer than the original loan term;
(C) to take and hold security for the payment of this Guaranty or the
Indebtedness, and exchange, enforce, waive, subordinate, fail or decide not to
perfect, and release any such security, with or without the substitution of new
collateral; (D) to release, substitute, agree not to sue, or deal with any one
or more of Borrower's sureties, endorsers, or other guarantors on any terms or
in any manner Lender may choose; (E) to determine how, when and what application
of payments and credits shall be made on the Indebtedness; (F) to apply such
security and direct the order or manner of sale thereof, including without
limitation, any nonjudicial sale permitted by the terms of the controlling
security agreement or deed of trust, as Lender in its discretion may determine;
(G) to sell, transfer, assign or grant participations in all or any part of the
Indebtedness; and (H) to assign or transfer this Guaranty in whole or in part.

GUARANTOR'S REPRESENTATIONS AND WARRANTIES.  Guarantor represents and warrants
to Lender that (A) no representations or agreements of any kind have been made
to Guarantor which would limit or qualify in any way the terms of this
Guaranty; (B) this Guaranty is executed at Borrower's request and not at the
request of Lender; (C) Guarantor has full power, right and authority to enter
into this Guaranty; (D) the provisions




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                              COMMERCIAL GUARANTY
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of this Guaranty do not conflict with or result in a default under any
agreement or other instrument binding upon Guarantor and do not result in a
violation of any law, regulation, court decree or order applicable to
Guarantor; (E) Guarantor has not and will not, without the prior written
consent of Lender, sell, lease, assign, encumber, hypothecate, transfer, or
otherwise dispose of all or substantially all of Guarantor's assets, or
any interest therein; (F) upon Lender's request, Guarantor will provide to
Lender financial and credit information in form acceptable to Lender, and all
such financial information which currently has been, and all future financial
information which will be provided to Lender is and will be true and correct
in all material respects and fairly present Guarantor's financial condition as
of the dates the financial information is provided; (G) no material adverse
change has occurred in Guarantor's financial condition since the date of the
most recent financial statements provided to Lender and no event has occurred
which may materially adversely affect Guarantor's financial condition; (H) no
litigation, claim, investigation, administrative proceeding or similar action
(including those for unpaid taxes) against Guarantor is pending or threatened;
(I) Lender has made no representation to Guarantor as to the creditworthiness
of Borrower; and (J) Guarantor has established adequate means of obtaining from
Borrower on a continuing basis information regarding Borrower's financial
condition. Guarantor agrees to keep adequately informed from such means of any
facts, events or circumstances which might in any way affect Guarantor's risks
under this Guaranty, and Guarantor further agrees that, absent a request for
information, Lender shall have no obligation to disclose to Guarantor any
information or documents acquired by Lender in the course of its relationship
with Borrower.

GUARANTOR'S WAIVERS. Except as prohibited by applicable law, Guarantor waives
any right to require Lender to (A) make any presentment, protest, demand, or
notice of any kind, including notice of change of any terms of repayment of the
Indebtedness, default by Borrower or any other guarantor or surety, any action
or nonaction taken by Borrower, Lender, or any other guarantor or surety of
Borrower, or the creation of new or additional Indebtedness; (B) proceed against
any person, including Borrower, before proceeding against Guarantor; (C) proceed
against any collateral for the Indebtedness, including Borrower's collateral,
before proceeding against Guarantor; (D) apply any payments or proceeds
received against the Indebtedness in any order; (E) give notice of the terms,
time, and place of any sale of the collateral pursuant to the Uniform Commercial
Code or any other law governing such sale; (F) disclose any information about
the Indebtedness, the Borrower, the collateral, or any other guarantor or
surety, or about any action or nonaction of Lender; or (G) pursue any remedy or
course of action in Lender's power whatsoever.

Guarantor also waives any and all rights or defenses arising by reason of (H)
any disability or other defense of Borrower, any other guarantor or surety or
any other person; (I) the cessation from any cause whatsoever, other than
payment in full, of the Indebtedness; (J) the application of proceeds of the
Indebtedness by Borrower for purposes other than the purposes understood and
intended by Guarantor and Lender; (K) any act of omission or commission by
Lender which directly or indirectly results in or contributes to the discharge
of Borrower or any other guarantor or surety, or the Indebtedness, or the loss
or release of any collateral by operation of law or otherwise; (L) any statute
of limitations in any action under this Guaranty or on the Indebtedness; or (M)
any modification or change in terms of the Indebtedness, whatsoever, including
without limitation, the renewal, extension, acceleration, or other change in
the time payment of the Indebtedness is due and any change in the interest
rate, and including any such modification or change in terms after revocation
of this Guaranty on Indebtedness incurred prior to such revocation.

Guarantor waives all rights and any defenses arising out of an election of
remedies by Lender even though that the election of remedies, such as a
non-judicial foreclosure with respect to security for a guaranteed obligation,
has destroyed Guarantor's rights of subrogation and reimbursement against
Borrower by operation of Section 580d of the California Code of Civil Procedure
or otherwise.

Guarantor waives all rights and defenses that Guarantor may have because
Borrower's obligation is secured by real property. This means among other
things: (1) Lender may collect from Guarantor without first foreclosing on any
real or personal property collateral pledged by Borrower. (2) If Lender
forecloses on any real property collateral pledged by Borrower: (a) the amount
of Borrower's obligation may be reduced only by the price for which the
collateral is sold at the foreclosure sale, even if the collateral is worth
more than the sale price. (b) Lender may collect from Guarantor even if Lender,
by foreclosing on the real property collateral, has destroyed any right
Guarantor may have to collect from Borrower. This is an unconditional waiver of
any rights and defenses Guarantor may have because Borrower's obligation is
secured by real property. These rights and defenses include, but are not
limited to, any rights and defenses based upon Section 580a, 580b, 580d, or 726
of the Code of Civil Procedure.

Guarantor understands and agrees that the foregoing waivers and waivers of
substantive rights and defenses to which Guarantor might otherwise be entitled
under state and federal law. The rights and defenses waived include, without
limitation, those provided by California laws of suretyship and guaranty,
anti-deficiency laws, and the Uniform Commercial Code. Guarantor acknowledges
that Guarantor has provided these waivers of rights and defenses with the
intention that they be fully relied upon by Lender. Until all Indebtedness is
paid in full, Guarantor waives any right to enforce any remedy Lender may have
against the Borrower or any other guarantor, surety, or other person, and
further, Guarantor waives any right to participate in any collateral for the
Indebtedness now or hereafter held by Lender.

In addition to the waivers set forth above, if now or hereafter Borrower is or
shall become insolvent and the Indebtedness shall not at all times until paid be
fully secured by collateral pledged by Borrower, Guarantor hereby forever waives
and gives up in favor of Lender and Borrower, and Lender's and Borrower's
respective successors, any claim or right to payment Guarantor may now have or
hereafter have or acquire against Borrower, by subrogation or otherwise, so that
at no time shall Guarantor be or become a "creditor" of Borrower within the
meaning of 11 U.S.C. section 547(b), or any successor provision of the Federal
bankruptcy laws.

GUARANTOR'S UNDERSTANDING WITH RESPECT TO WAIVERS. Guarantor warrants and
agrees that each of the waivers set forth above is made with Guarantor's full
knowledge of its significance and consequences and that, under the
circumstances, the waivers are reasonable and not contrary to public policy or
law. If any such waiver is determined to be contrary to any applicable law or
public policy, such waiver shall be effective only to the extent permitted by
law or public policy.

SUBORDINATION OF BORROWER'S DEBTS TO GUARANTOR. Guarantor agrees that the
Indebtedness of Borrower to Lender, whether now existing or hereafter created,
shall be superior to any claim that Guarantor may now have or hereafter acquire
against Borrower, whether or not Borrower becomes insolvent. Guarantor hereby
expressly subordinates any claim Guarantor may have against Borrower, upon any
account whatsoever, to any claim that Lender may now or hereafter have against
Borrower. In the event of insolvency and consequent liquidation of the assets
of Borrower, through bankruptcy, by an assignment for the benefit of creditors,
by voluntary liquidation, or otherwise, the assets of Borrower applicable to
the payment of the claims of both Lender and Guarantor shall be paid to Lender
and shall be first applied by Lender to the Indebtedness of Borrower to Lender.
Guarantor does hereby assign to Lender all claims which it may have or acquire
against Borrower or against any assignee or trustee in bankruptcy of Borrower;
provided however, that such assignment shall be effective only for the purposes
of assuring to Lender full payment in legal tender of the Indebtedness. If
Lender so requests, any notes or credit agreements now or hereafter evidencing
any debts or obligations of Borrower to Guarantor shall be marked with a legend
that the same are subject to this Guaranty and shall be delivered to Lender.
Guarantor agrees, and Lender is herby authorized, in the name of Guarantor,
from time to time to execute and file financing statements and continuation
statements and to execute such other documents and to take such other actions
as Lender deems necessary or appropriate to perfect, preserve and enforce its
rights under this Guaranty.

MISCELLANEOUS PROVISIONS. The following miscellaneous provisions are a part of
this Guaranty:

     AMENDMENTS. This Guaranty, together with any Related Documents, constitutes
     the entire understanding and agreement of the parties as to the matters set
     forth in this Guaranty. No alteration of or amendment to this Guaranty
     shall be effective unless given in writing and signed by the party or
     parties sought to be charged or bound by the alteration or amendment.

     ATTORNEY'S FEES; EXPENSES. Guarantor agrees to pay upon demand all of
     Lender's costs and expenses, including Lender's attorney's fees and
     Lender's legal expenses, incurred in connection with the enforcement of
     this Guaranty. Lender may hire or pay someone else to help enforce this

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                              COMMERCIAL GUARANTY
                                  (CONTINUED)                             PAGE 3
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     Guaranty, and Guarantor shall pay the costs and expenses of such
     enforcement. Costs and expenses include Lender's attorneys' fees and legal
     expenses whether or not there is a lawsuit, including attorneys' fees and
     legal expenses for bankruptcy proceedings (including efforts to modify or
     vacate any automatic stay or injunction), appeals, and any anticipated
     post-judgment collection services. Guarantor also shall pay all court costs
     and such additional fees as may be directed by the court.

     CAPTION HEADINGS. Caption headings in this Guaranty are for convenience
     purposes only and are not to be used to interpret or define the provisions
     of this Guaranty.

     GOVERNING LAW. THIS GUARANTY WILL BE GOVERNED BY, CONSTRUED AND ENFORCED IN
     ACCORDANCE WITH FEDERAL LAW AND THE LAWS OF THE STATE OF CALIFORNIA. THIS
     GUARANTY HAS BEEN ACCEPTED BY LENDER IN THE STATE OF CALIFORNIA.

     CHOICE OF VENUE. If there is a lawsuit, Guarantor agrees upon Lender's
     request to submit to the jurisdiction of the courts of San Diego Country,
     State of California.

     INTEGRATION. Guarantor further agrees that Guarantor has read and fully
     understands the terms of this Guaranty; Guarantor has had the opportunity
     to be advised by Guarantor's attorney with respect to this Guaranty; the
     Guaranty fully reflects Guarantor's intentions and parol evidence is not
     required to interpret the terms of this Guaranty. Guarantor hereby
     indemnifies and holds Lender harmless from all losses, claims, damages, and
     costs (including Lender's attorneys' fees) suffered or incurred by Lender
     as a result of any breach by Guarantor of the warranties, representations
     and agreements of this paragraph.

     INTERPRETATION. In all cases where there is more than one Borrower or
     Guarantor, then all words used in this Guaranty in the singular shall be
     deemed to have been used in the plural where the context and construction
     so require; and where there is more than one Borrower named in this
     Guaranty or when this Guaranty is executed by more than one Guarantor, the
     words "Borrower" and "Guarantor" respectively shall mean all and any one or
     more of them. The words "Guarantor," "Borrower," and "Lender" include the
     heirs, successors,  assigns and transferees of each of them. If a court
     finds that any provision of this Guaranty is not valid or should not be
     enforced, that fact by itself will not mean that the rest of this Guaranty
     will not be valid or enforced. Therefore, a court will enforce the rest of
     the provisions of this Guaranty even if a provision of this Guaranty may be
     found to be invalid or enforceable. If any one or more of Borrower or
     Guarantor are corporations, partnerships, limited liability companies, or
     similar entities, it is not necessary for Lender to inquire into the powers
     of Borrower or Guarantor or of the officers, directors, partners, managers,
     or other agents acting or purporting to act on their behalf, and any Loan
     indebtedness made or created in reliance upon the professed exercise of
     such powers shall be guaranteed under this Guaranty.

     NOTICES. Any notice required to be given under this Guaranty shall be given
     in writing, and, except for revocation notices by Guarantor, shall be
     effective when actually delivered, when actually received by telefacsimile
     (unless otherwise required by law), when deposited with a nationally
     recognized overnight courier, or, if mailed, when deposited in the United
     States mail, as first class, certified or registered mail postage prepaid,
     directed to the addresses shown near the beginning of this Guaranty. All
     revocation notices by Guarantor shall be in writing and shall be effective
     upon delivery to Lender as provided in the section of this Guaranty
     entitled "DURATION OF GUARANTY." Any party may change its address for
     notices under this Guaranty by giving formal written notice to the other
     parties, specifying that the purpose of the notice is to change the party's
     address. For notice purposes, Guarantor agrees to keep Lender informed at
     all times of Guarantor's current address. Unless otherwise provided or
     required by law, if there is more than one Guarantor, any notice given by
     Lender to any Guarantor is deemed to be notice given to all Guarantors.

     NO WAIVER BY LENDER. Lender shall not be deemed to have waived any rights
     under this Guaranty unless such waiver is given in writing and signed by
     Lender. No delay or omission on the part of Lender in exercising any right
     shall operate as a waiver of such right or any other right. A waiver by
     Lender of a provision of this Guaranty shall not prejudice or constitute a
     waiver of Lender's right otherwise to demand strict compliance with that
     provision or any other provision of this Guaranty. No prior waiver by
     Lender, nor any course of dealing between Lender and Guarantor, shall
     constitute a waiver of any of Lender's rights or of any of Guarantor's
     obligations as to any future transactions. Whenever the consent of Lender
     is required under this Guaranty, the granting of such consent by Lender in
     any instance shall not constitute continuing consent to subsequent
     instances where such consent is required and in all cases such consent may
     be granted or withheld in the sole discretion of Lender.

     SUCCESSORS AND ASSIGNS. Subject to any limitations stated in this Guaranty
     on transfer of Guarantor's interest, this Guaranty shall be binding upon
     and inure to the benefit of the parties, their successors and assigns.

     WAIVE JURY. Lender and Guarantor hereby waive right to any jury trial in
     any action, proceeding, or counterclaim brought by either Lender or
     Borrower against the other.

DEFINITIONS. The following capitalized words and terms shall have the following
meanings when used in this Guaranty. Unless specifically stated to the contrary,
all references to dollar amounts shall mean amounts in lawful money of the
United States of America. Words and terms used in the singular shall include the
plural, and the plural shall include the singular, as the context may require.
Words and terms not otherwise defined in this Guaranty shall have the meanings
attributed to such terms in the Uniform Commercial Code:

     BORROWER. The word "Borrower" means Agricultural Supply, Inc., a Delaware
     corporation, and all other persons and entities signing the Note in
     whatever capacity.

     GUARANTOR. The word "Guarantor" means each and every person or entity
     signing this Guaranty, including without limitation Max Gelwix and William
     B. Adams.

     GUARANTY. The word "Guaranty" means the guaranty from Guarantor to
     Lender, including without limitation a guaranty of all or part of the Note.

     INDEBTEDNESS. The word "Indebtedness" means Borrower's indebtedness to
     Lender as more particularly described in this Guaranty.

     LENDER. The word "Lender" means First National Bank, its successors and
     assigns.

     RELATED DOCUMENTS. The words "Related Documents" means all promissory
     notes, credit agreements, loan agreements, environmental agreements,
     guaranties, security agreements, mortgages, deeds of trust, security
     deeds, collateral mortgages, and all other instruments, agreements and
     documents, whether now or hereafter existing, executed in connection with
     the indebtedness.


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GUARANTOR ACKNOWLEDGES HAVING READ ALL THE PROVISIONS OF THIS COMMERCIAL
GUARANTY AND GUARANTOR AGREES TO ITS TERMS. THIS COMMERCIAL GUARANTY IS DATED
JUNE 1, 2000.

X  /s/ MAX GELWIX                       X  /s/ WILLIAM B. ADAMS
 ----------------------------------      --------------------------------------
 Max Gelwix, Individually                William B. Adams, Individually

Signed, acknowledged and delivered
in the presence of:

X  /S/ DAVID S. WALTERS
 ----------------------------------
 Witness

X
 ----------------------------------
 Witness