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                                                                   EXHIBIT 10.1


                    FIRST AMENDMENT TO AMENDED AND RESTATED
                            ASSET PURCHASE AGREEMENT

          This First Amendment to Amended and Restated Asset Purchase
Agreement (the "Amendment") is entered into as of June 9, 2000 by and among
Eco Soil Systems, Inc., a Nebraska corporation ("Parent"), Turf Partners,
Inc., a Delaware corporation ("Seller"), and J.R. Simplot Company, a Nevada
corporation ("Buyer"). Parent, Seller and Buyer are hereinafter referred to
as the "Parties."

          WHEREAS, the Parties entered into an Asset Purchase Agreement dated
as of March 27, 2000; and

          WHEREAS, the Parties later agreed to certain amendments to the
Asset Purchase Agreement which were reflected in an Amended and Restated
Asset Purchase Agreement dated as of April 5, 2000 (as amended, the
"Agreement"); and

          WHEREAS, the Parties now wish to amend the provisions of the
Agreement regarding, among other things, (i) the purchase price and (ii)
termination of the Agreement; and

          WHEREAS, the board of directors of Parent has unanimously approved
this Amendment and has resolved to recommend to Parent's shareholders that
they approve the transactions contemplated by the Agreement as amended
hereby; and

          WHEREAS, concurrently with the execution and delivery of this
Amendment, (i) Buyer has arranged a $2 million letter of credit to secure
Parent's obligations under a Term Loan and Security Agreement with Coast
Business Credit; (ii) Buyer is prepared to lend Parent and Seller $3 million
pursuant to that certain Term Loan Agreement dated as of April 12, 2000 among
Buyer, Parent and Seller; (iii) Parent and Buyer have agreed upon the final
terms of each of the Ancillary Agreements (as defined in the Agreement); (iv)
the Parties have entered into a corporate governance agreement pursuant to
which Buyer will manage the operations of Seller pending the Closing (as
defined in the Agreement); and (v) each member of Parent's board of directors
has entered into a Shareholder Voting Agreement pursuant to which such
directors have agreed to vote their shares of Parent common stock in favor of
the transactions contemplated by the Agreement as amended hereby; and

          WHEREAS, the Parties believe this Amendment will benefit each of
them.

          NOW, THEREFORE, for good and valuable consideration, receipt of
which is hereby acknowledged, the Parties hereto agree as follows:

          1. The following defined terms shall be deleted from Section 1.1:
"EBITDA" and "Net Tangible Assets."

          2. The term "Closing Date" as defined in Section 1.1 shall be
revised to state in its entirety as follows:

                 "CLOSING DATE" shall mean a date two business days following
             the satisfaction or waiver of all conditions to the obligations of
             Buyer and Seller to consummate the transactions contemplated hereby
             (other than conditions with respect to actions Buyer and Seller
             will take at the Closing itself) to be agreed upon by Buyer and
             Seller or such other date as Buyer and Seller shall mutually agree
             upon."

          3. The following defined terms and the corresponding section
references shall be deleted from the table contained in Section 1.2:
"Adjustment Amount," "June 30, 2000 Balance Sheet" and "Net Book Value."

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          4. Section 2.4 of the Agreement shall be revised to state in its
entirety as follows:

                 "2.4 PURCHASE PRICE. The purchase price for the Assets (the
             "Purchase Price") shall be Twenty-Three Million Dollars
             ($23,000,000). On the Closing Date, Buyer will pay (i) Twenty-One
             Million Nine Hundred Seventy-Five Thousand Dollars ($21,975,000)
             to Seller by wire transfer to an account designated by Seller prior
             to the Closing and (ii) One Million Twenty-Five Thousand Dollars
             ($1,025,000), on behalf of Seller, by wire transfer to an account
             provided to Buyer prior to the Closing in respect of certain
             expenses incurred by Seller in connection with the transactions
             contemplated hereby, as specified on Schedule 2.4 hereto."

          5. Section 2.5 of the Agreement shall be revised to state in its
entirety as follows:

                 "2.5 REPAYMENT OF TERM LOAN. On the Closing Date, Seller shall
             repay all amounts outstanding, together with any interest thereon,
             on the $3 million term loan made by Buyer to Parent and Seller
             under that certain Term Loan Agreement dated as of April 12, 2000
             among Buyer, Parent and Seller."

          6. Section 2.6 shall be revised to state in its entirety as follows:

                 "2.6 CLOSING BALANCE SHEET. On or before August 15, 2000,
             Seller shall prepare and deliver to Buyer, an audited balance sheet
             as of June 30, 2000 (the "Closing Balance Sheet"). The Closing
             Balance Sheet shall be prepared by Seller's personnel in accordance
             with generally accepted accounting principles, as applied in
             preparation of the Balance Sheet, and shall fairly and accurately
             present the Assets, Liabilities (including reserves) and financial
             position of the Business, with respect to the Assets, as of
             June 30, 2000."

          7. Section 2.8 shall be revised to state in its entirety as follows:

                 "2.8 PRORATIONS. All rent, utilities and other lease charges
             with respect to Leases assumed by Buyer shall be prorated between
             Buyer and Seller as of June 30, 2000. Such prorations shall,
             insofar as feasible, be determined and paid at the Closing, with
             best efforts to achieve final settlement of such prorations within
             30 days after the Closing. Seller shall be responsible for payment
             of all unpaid rent, common area maintenance expenses and real
             property taxes through June 30, 2000."

          8. The third sentence of Section 6.1 shall be revised to state in
its entirety as follows:

                 "As soon as practical after the execution and delivery of this
             Agreement, but no later than June 13, 2000, Buyer and Seller shall
             make all filings required under the HSR Act, and Buyer and Seller
             will promptly file any supplemental or additional information which
             may reasonably be requested in connection therewith pursuant to the
             HSR Act, and will comply in all material respects with the
             requirements of the HSR Act."

          9. Sections 6.11, 8.6 and 10.7 of the Agreement shall be deleted in
their entirety.

         10. Clause (vi) of Section 11.1(a) of the Agreement shall be deleted
in its entirety.

         11. The effectiveness of this Amendment is subject to the approval
of the boards of directors of Seller and Parent on or before June 9, 2000.
Prior to such approvals, this Amendment shall have no force or effect. Seller
and Parent will deliver certified copies of their board resolutions to Buyer
on or prior to June 13, 2000.

         12. This Amendment may be executed in one or more counterparts, and
by different parties hereto in separate counterparts, each of which when
executed shall be deemed to be an original, including counterparts
transmitted by facsimile, but all of which taken together shall constitute
one and the same agreement.

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         13. On and after the date hereof, each reference in the Agreement to
the "Agreement" shall mean the Agreement as amended hereby. Except as
specifically amended above, the Agreement shall remain in full force and
effect and is hereby ratified and confirmed. The execution, delivery and
effectiveness of this Amendment shall not, except as expressly provided
herein, operate as a waiver of any right, power or remedy of any party
hereto, nor constitute a waiver of any provision of the Agreement.

                            [Signature page follows]

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    IN WITNESS HEREOF, the Parties have entered into this Amendment as of the
date first written above.

<TABLE>

<S>                                                     <C>
PARENT:                                                 BUYER:

ECO SOIL SYSTEMS, INC.                                  J.R. SIMPLOT COMPANY

By: /s/ William B. Adams                                By: /s/ Stephen A. Beebe
   ---------------------------------------              ------------------------------------------
Name: William B. Adams                                  Name: Stephen A. Beebe
      ------------------------------------              ------------------------------------------
Its: Chairman/CEO                                       Its: President and CEO
   ---------------------------------------              ------------------------------------------

SELLER:

TURF PARTNERS, INC.

By: /s/ William B. Adams
   ---------------------------------------
Name: William B. Adams
      ------------------------------------
Its: Chairman/CEO
   ---------------------------------------

</TABLE>


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                                  SCHEDULE 2.4

         On the Closing Date, the amount of $1,025,000 shall be paid by Buyer
to CIBC World Markets Corp. ("CIBC World Markets") in respect of certain fees
owed by Seller to CIBC World Markets.


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