FORM 10-K405

                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C.  20549

               Annual Report Pursuant to Section 13 or 15(d) of
                      the Securities Exchange Act of 1934

For the fiscal year ended December 31, 1998

Commission File Number 0-16331

                        DYCO OIL AND GAS PROGRAM 1986-X
                            (A LIMITED PARTNERSHIP)
            (Exact name of registrant as specified in its charter)

           Minnesota                       41-1565819
(State or other jurisdiction of          (I.R.S. Employer
incorporation or organization)        Identification Number)

         Samson Plaza
   Two West Second Street
        Tulsa, Oklahoma                       74103
     (Address of principal                  (Zip Code)
      executive offices)

Registrant's telephone number, including area code: (918) 583-1791

Securities registered pursuant to Section 12(b) of the Act:  None.

Securities registered pursuant to Section 12(g) of the Act:
      Units of limited partnership interest

      Indicate by check mark  whether the  registrant  (1) has filed all reports
required to be filed by Section 13 or 15(d) of the  Securities  Exchange  Act of
1934  during  the  preceding  12 months  (or for such  shorter  period  that the
registrant was required to file such  reports),  and (2) has been subject to the
filing requirements for the past 90 days. Yes [X] No [ ]

     Indicate by check mark if disclosure of delinquent  filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's  knowledge,  in definitive proxy or information  statements
incorporated  by reference in Part III of this Form 10-K405 or any  amendment to
this Form 10-K405. [X]

      The units of  limited  partnership  are not  publicly  traded,  therefore,
registrant cannot compute the aggregate market value of the voting units held by
non-affiliates of the registrant.

      DOCUMENTS INCORPORATED BY REFERENCE:  None.



                                      -1-
<PAGE>



                                 FORM 10-K405

                        DYCO OIL AND GAS PROGRAM 1986-X
                       (a Minnesota limited partnership)


                               TABLE OF CONTENTS


PART I.......................................................................3
      ITEM 1.     BUSINESS...................................................3
      ITEM 2.     PROPERTIES.................................................7
      ITEM 3.     LEGAL PROCEEDINGS.........................................11
      ITEM 4.     SUBMISSION OF MATTERS TO A VOTE OF LIMITED PARTNERS.......11
PART II.....................................................................11
      ITEM 5.     MARKET FOR THE REGISTRANT'S LIMITED PARTNERSHIP UNITS 
                  AND RELATED LIMITED PARTNER MATTERS.......................11
      ITEM 6.     SELECTED FINANCIAL DATA...................................12
      ITEM 7.     MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL 
                  CONDITION AND RESULTS OF OPERATIONS.......................13
      ITEM 7A.    QUANTITATIVE AND QUALITATIVE DISCLOSURES
                  ABOUT MARKET RISK.........................................21
      ITEM 8.     FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA...............22
      ITEM 9.     CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON 
                  ACCOUNTING AND FINANCIAL DISCLOSURE.......................33
PART III....................................................................33
      ITEM 10.    DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT........33
      ITEM 11.    EXECUTIVE COMPENSATION....................................34
      ITEM 12.    SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND 
                  MANAGEMENT ...............................................38
      ITEM 13.    CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS............38
PART IV.....................................................................40
      ITEM 14.    EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON 
                  FORM 8-K .................................................40
      SIGNATURES............................................................42





                                      -2-
<PAGE>



                                     PART I


ITEM 1.     BUSINESS

      General

      The Dyco Oil and Gas Program 1986-X Limited Partnership (the "Program") is
a Minnesota  limited  partnership  engaged in the production of oil and gas. The
Program  commenced  operations  on December 12, 1986 with the primary  financial
objective of investing its limited  partners'  subscriptions  in the drilling of
oil  and gas  prospects  and  then  distributing  to its  limited  partners  all
available  cash flow from the Program's  on-going  production  operations.  Dyco
Petroleum Corporation ("Dyco") serves as the General Partner of the Program. See
"Item 2. Properties" for a description of the Program's reserves and properties.

      The  limited   partnership   agreement   for  the  Program  (the  "Program
Agreement")  provides  that limited  partners are  allocated  99% of all Program
costs and revenues and Dyco, as General Partner,  is allocated 1% of all Program
costs and  revenues.  Included in such costs is the Program's  reimbursement  to
Dyco of the Program's proportionate share of Dyco's geological, engineering, and
general and administrative expenses.

      Dyco  currently  serves as General  Partner  of 31  limited  partnerships,
including the Program.  Dyco is a wholly-owned  subsidiary of Samson  Investment
Company.  Samson  Investment  Company  and its various  corporate  subsidiaries,
including Dyco, (collectively, "Samson") are primarily engaged in the production
and  development of and exploration for oil and gas reserves and the acquisition
and  operation  of  producing  properties.  At January 31,  1999,  Samson  owned
interests in approximately  10,500 oil and gas wells located in 19 states of the
United States and the countries of Canada, Venezuela, and Russia. At January 31,
1999, Samson operated approximately 2,900 oil and gas wells located in 15 states
of the United States, as well as Canada, Venezuela, and Russia.

      As a limited  partnership,  the Program  has no  officers,  directors,  or
employees. It relies instead on the personnel of Dyco and Samson. As of March 1,
1999,  Samson employed  approximately  900 persons.  No employees are covered by
collective bargaining agreements, and management believes that Samson provides a
sound employee relations  environment.  For information  regarding the executive
officers  of Dyco,  see  "Item  10.  Directors  and  Executive  Officers  of the
Registrant."

      Dyco's and the Program's  principal place of business is located at Samson
Plaza, Two West Second Street, Tulsa, Oklahoma 74103, and their telephone number
is (918) 583-1791 or (800) 283-1791.



                                      -3-
<PAGE>



      Funding

      Although the Program  Agreement  permits the Program to incur  borrowings,
the Program's  operations and expenses are currently funded out of the Program's
revenues from oil and gas sales. Dyco may, but is not required to, advance funds
to  the  Program  for  the  same  purposes  for  which  Program  borrowings  are
authorized.


      Principal Products Produced and Services Rendered

      The Program's sole business is the  development  and production of oil and
gas with a  concentration  on gas.  The  Program  does  not  hold  any  patents,
trademarks,  licenses,  or  concessions  and is not a  party  to any  government
contracts.  The  Program  has no backlog of orders and does not  participate  in
research and development  activities.  The Program is not presently encountering
shortages of oilfield tubular goods, compressors,  production material, or other
equipment.


      Oil, Gas, and Environmental Control Regulations

      Regulation  of Production  Operations -- The  production of oil and gas is
subject to  extensive  federal and state laws and  regulations  governing a wide
variety of matters, including the drilling and spacing of wells, allowable rates
of  production,  prevention  of  waste  and  pollution,  and  protection  of the
environment.  In  addition  to the direct  costs  borne in  complying  with such
regulations,  operations and revenues may be impacted to the extent that certain
regulations limit oil and gas production to below economic levels.

      Regulation  of Sales and  Transportation  of Oil and Gas -- Sales of crude
oil and  condensate are made by the Program at market prices and are not subject
to price controls. The sale of gas may be subject to both federal and state laws
and  regulations.  The provisions of these laws and  regulations are complex and
affect all who  produce,  resell,  transport,  or purchase  gas,  including  the
Program.  Although  virtually all of the Program's gas production is not subject
to  price  regulation,   other  regulations   affect  the  availability  of  gas
transportation services and the ability of gas consumers to continue to purchase
or use gas at current levels. Accordingly,  such regulations may have a material
effect  on the  Program's  operations  and  projections  of  future  oil and gas
production and revenues.

      Future  Legislation --  Legislation  affecting the oil and gas industry is
under  constant  review  for  amendment  or  expansion.  Because  such  laws and
regulations  are frequently  amended or  reinterpreted,  management is unable to
predict what additional



                                      -4-
<PAGE>



energy  legislation  may be proposed or enacted or the future cost and impact of
complying with existing or future regulations.

      Regulation of the  Environment -- The Program's  operations are subject to
numerous laws and  regulations  governing  the  discharge of materials  into the
environment or otherwise relating to environmental  protection.  Compliance with
such  laws  and  regulations,   together  with  any  penalties   resulting  from
noncompliance,  may increase the cost of the Program's  operations or may affect
the  Program's  ability  to  timely  complete  existing  or  future  activities.
Management  anticipates  that various local,  state,  and federal  environmental
control agencies will have an increasing impact on oil and gas operations.


      Significant Customers

      Purchases  of gas by El Paso  Energy  Marketing  Company  ("El  Paso") and
Transok, Inc. accounted for approximately 86.9% and 10.5%, respectively,  of the
Program's oil and gas revenues  during the year ended  December 31, 1998. In the
event of  interruption  of  purchases  by  these  significant  customers  or the
cessation or material change in availability  of open-access  transportation  by
the Program's  pipeline  transporters,  the Program may encounter  difficulty in
marketing  its  gas  and  in  maintaining  historic  sales  levels.  Alternative
purchasers or transporters may not be readily available.

      The Program's  principal  customers for crude oil  production are refiners
and other companies which have pipeline facilities near the producing properties
of the Program. In the event pipeline facilities are not conveniently  available
to  production  areas,  crude oil is usually  trucked by  purchasers  to storage
facilities.


      Competition and Marketing

      The  domestic  oil and gas  industry is highly  competitive,  with a large
number of companies and  individuals  engaged in the exploration and development
of oil and gas properties.  The ability of the Program to produce and market oil
and gas profitably depends on a number of factors that are beyond the control of
the Program.  These factors include worldwide political instability  (especially
in oil-producing regions), United Nations export embargoes, the supply and price
of foreign  imports of oil and gas, the level of consumer  product demand (which
can be heavily  influenced  by weather  patterns),  government  regulations  and
taxes,  the price and  availability of alternative  fuels,  the overall economic
environment,  and the availability and capacity of transportation and processing
facilities.  In addition,  on March 12, 1999 several major oil producing nations
agreed to curtail oil exports in an effort to increase worldwide



                                      -5-
<PAGE>



oil prices.  The effect of these  factors on future oil and gas industry  trends
cannot be accurately predicted or anticipated.

      The most important variable affecting the Program's revenues is the prices
received for the sale of oil and gas.  Predicting future prices is not possible.
Concerning past trends,  average yearly wellhead gas prices in the United States
have been volatile for a number of years.  For the past ten years,  such average
prices have generally been in the $1.40 to $2.40 per Mcf range.

      Substantially  all of the  Program's  gas  reserves  are being sold on the
"spot  market."  Prices on the spot  market  are  subject to wide  seasonal  and
regional pricing  fluctuations due to the highly  competitive nature of the spot
market. In addition,  such spot market sales are generally  short-term in nature
and are dependent  upon the  obtaining of  transportation  services  provided by
pipelines.  Spot prices for the Program's gas decreased from approximately $2.32
per Mcf at December  31,  1997 to  approximately  $1.93 per Mcf at December  31,
1998.  Such prices  were on an MMBTU  basis and differ from the prices  actually
received  by  the  Program  due  to  transportation  and  marketing  costs,  BTU
adjustments, and regional price and quality differences.  Continued very low oil
prices as discussed below may cause downward  pressure on gas prices due to some
users of gas converting to oil as a cheaper fuel alternative.

      For the past ten years,  average  oil prices  have  generally  been in the
$16.00 to $24.00 per barrel range.  Due to global  consumption and supply trends
over the last year as well as at least a  short-term  slowdown  in Asian  energy
demand,  oil prices  over the past year have  reached  historically  low levels,
dropping to as low as  approximately  $9.00 per barrel.  It is not known whether
this  trend  will  continue.   Prices  for  the  Program's  oil  decreased  from
approximately  $16.25 per barrel at December 31, 1997 to approximately $9.50 per
barrel at December 31, 1998.

      As of February  28, 1999 oil and gas prices were  approximately  $9.50 per
barrel and $1.55 per Mcf, respectively.  Future prices for both oil and gas will
likely  be  different  from  (and may be lower  than)  the  prices  in effect on
December 31, 1998 and February 28, 1999.  As of the date of this Annual  Report,
oil prices have increased  slightly over the February 28, 1999 price,  primarily
due to the March 1999  announcement that several oil producing nations intend to
curtail oil exports.  Management is unable to predict whether future oil and gas
prices will (i) stabilize, (ii) increase, or (iii) decrease.


      Insurance Coverage

     The Program is subject to all of the risks inherent in the  exploration for
and production of oil and gas, including blowouts,  pollution,  fires, and other
casualties. The Program



                                      -6-
<PAGE>



maintains  insurance  coverage as is  customary  for  entities of a similar size
engaged in operations similar to that of the Program,  but losses can occur from
uninsurable risks or in amounts in excess of existing  insurance  coverage.  The
occurrence  of an event  which is not fully  covered by  insurance  could have a
material  adverse  effect on the  Program's  financial  condition and results of
operations.


ITEM 2.     PROPERTIES

      Well Statistics

      The  following  table sets forth the  numbers of gross and net  productive
wells of the Program as of December 31, 1998.

                              Well Statistics(1)

                            As of December 31, 1998

                  Gross productive wells(2):
                     Oil                                 -
                     Gas                                 8
                                                      ----
                        Total                            8

                  Net productive wells(3):
                     Oil                                 -
                     Gas                              1.21
                                                      ----
                        Total                         1.21

----------
(1)   The designation of a well as an oil well or gas well is made by Dyco based
      on the relative amount of oil and gas reserves for the well. Regardless of
      a well's oil or gas designation,  it may produce oil, gas, or both oil and
      gas.
(2)   As used  throughout  this Annual  Report on Form 10-K  ("Annual  Report"),
      "Gross  Well" refers to a well in which a working  interest is owned.  The
      number  of gross  wells is the  total  number  of wells in which a working
      interest is owned.
(3)   As used throughout this Annual Report, "Net Well" refers to the sum of the
      fractional  working  interests  owned in gross wells.  For example,  a 15%
      working interest in a well represents one Gross Well, but 0.15 Net Well.


      Drilling Activities

      The  Program  participated  in no drilling  activities  for the year ended
December 31, 1998.





                                      -7-
<PAGE>



      Oil and Gas Production, Revenue, and Price History

      The following table sets forth certain historical  information  concerning
the oil  (including  condensates)  and  gas  production,  net of all  royalties,
overriding royalties, and other third party interests, of the Program,  revenues
attributable to such production, and certain price and cost information.

                              Net Production Data

                                                Year Ended December 31,
                                          ----------------------------------
                                            1998          1997        1996
                                          --------      --------    --------

Production:
   Oil (Bbls)(1)                               264           305         307
   Gas (Mcf)(2)                             67,903        80,262      87,534

Oil and gas sales:
   Oil                                    $  3,428      $  6,060    $  5,915
   Gas                                     131,652       186,238     185,703
                                           -------       -------     -------
      Total                               $135,080      $192,298    $191,618
                                           =======       =======     =======

Total direct operating expenses(3)        $ 43,514      $ 57,433    $ 64,580
                                           =======       =======     =======

Direct operating expenses as a
   percentage of oil and gas
   sales                                     32.2%         29.9%       33.7%

Average sales price:
   Per barrel of oil                        $12.98        $19.87      $19.27
   Per Mcf of gas                             1.94          2.32        2.12

Direct operating expenses per
   equivalent Mcf of gas(4)                 $  .63        $  .70      $  .72

----------

(1)  As  used throughout this Annual Report, "Bbls" refers to barrels of 42 U.S.
     gallons and  represents  the basic unit for  measuring  the  production of
     crude oil and condensate oil.
(2)  As  used  throughout  this Annual  Report,  "Mcf" refers to volume of 1,000
     cubic feet under  prescribed  conditions of pressure and  temperature  and
     represents the basic unit for measuring the production of gas.
(3)  Includes lease operating expenses and production taxes.
(4)  Oil  production is converted to gas  equivalents at the rate of six Mcf per
     barrel,  representing the estimated relative energy content of gas and oil,
     which rate is not necessarily indicative of the relationship of oil and gas
     prices. The



                                      -8-
<PAGE>



      respective  prices of oil and gas are affected by market and other factors
      in addition to relative energy content.


      Proved Reserves and Net Present Value

      The following table sets forth the Program's  estimated proved oil and gas
reserves and net present value  therefrom as of December 31, 1998.  The schedule
of  quantities of proved oil and gas reserves was prepared by Dyco in accordance
with the rules prescribed by the Securities and Exchange Commission (the "SEC").
As used  throughout  this  Annual  Report,  "proved  reserves"  refers  to those
estimated  quantities of crude oil, gas, and gas liquids  which  geological  and
engineering  data  demonstrate  with  reasonable  certainty to be recoverable in
future  years from known oil and gas  reservoirs  under  existing  economic  and
operating conditions.

      Net present  value  represents  estimated  future gross cash flow from the
production and sale of proved reserves,  net of estimated oil and gas production
costs (including  production  taxes, ad valorem taxes, and operating  expenses),
and estimated future development costs, discounted at 10% per annum. Net present
value  attributable to the Program's proved reserves was calculated on the basis
of current costs and prices at December 31, 1998. Such prices were not escalated
except in  certain  circumstances  where  escalations  were  fixed  and  readily
determinable in accordance with applicable contract provisions.  The prices used
by Dyco in  calculating  the net present  value  attributable  to the  Program's
proved  reserves  do not  necessarily  reflect  market  prices  for  oil and gas
production  subsequent to December 31, 1998.  There can be no assurance that the
prices  used in  calculating  the net  present  value  of the  Program's  proved
reserves at December 31, 1998 will actually be realized for such production.

      The process of  estimating  oil and gas  reserves  is  complex,  requiring
significant  subjective  decisions in the  evaluation  of available  geological,
engineering,  and  economic  data  for  each  reservoir.  The  data  for a given
reservoir may change substantially over time as a result of, among other things,
additional development activity, production history, and viability of production
under varying economic conditions;  consequently, it is reasonably possible that
material  revisions to existing reserve  estimates may occur in the near future.
Although  every  reasonable  effort has been made to ensure  that these  reserve
estimates represent the most accurate assessment  possible,  the significance of
the  subjective  decisions  required and variances in available data for various
reservoirs  make these  estimates  generally  less precise than other  estimates
presented in connection with financial statement disclosures.




                                      -9-
<PAGE>



                               Proved Reserves and
                                Net Present Value
                              From Proved Reserves

                             As of December 31, 1998

            Estimated proved reserves:
               Gas (Mcf)                                  580,740
               Oil and liquids (Bbls)                         905

            Net present value
               (discounted at 10% per annum)             $606,507


      No estimates  of the proved  reserves of the Program  comparable  to those
included  herein have been included in reports to any federal  agency other than
the SEC.  Additional  information  relating to the Program's  proved reserves is
contained in Note 4 to the Program's financial statements, included in Item 8 of
this Annual Report.


      Significant Properties

      As of December 31, 1998,  the  Program's  properties  consisted of 8 gross
(1.21 net)  productive  wells.  The Program  owns an interest in one  additional
well.  Affiliates  of the  Program  operate  8 (89%)  of its  wells.  All of the
Program's reserves are located in the Anadarko Basin of western Oklahoma and the
Texas panhandle, which is an established oil and gas producing basin.


      Title to Oil and Gas Properties

      Management believes that the Program has satisfactory title to its oil and
gas properties. Record title to substantially all of the Program's properties is
held by Dyco as nominee.

      Title  to the  Program's  properties  is  subject  to  customary  royalty,
overriding  royalty,   carried,   working,   and  other  similar  interests  and
contractual  arrangements  customary in the oil and gas  industry,  to liens for
current taxes not yet due, and to other  encumbrances.  Management believes that
such burdens do not materially detract from the value of such properties or from
the Program's  interest  therein or materially  interfere  with their use in the
operation of the Program's business.




                                      -10-
<PAGE>




ITEM 3.     LEGAL PROCEEDINGS

      To the knowledge of the management of Dyco and the Program,  neither Dyco,
the Program,  nor the Program's  properties are subject to any  litigation,  the
results  of which  would  have a  material  effect  on the  Program's  or Dyco's
financial condition or operations.


ITEM 4.     SUBMISSION OF MATTERS TO A VOTE OF LIMITED PARTNERS

      There were no matters  submitted to a vote of the limited  partners during
1998.

                                    PART II

ITEM 5.     MARKET FOR THE REGISTRANT'S LIMITED PARTNERSHIP UNITS AND RELATED
            LIMITED PARTNER MATTERS

      The Program does not have an  established  trading market for its units of
limited  partnership  interest  ("Units").  Pursuant to the terms of the Program
Agreement, Dyco, as General Partner, is obligated to annually issue a repurchase
offer which is based on the  estimated  future net revenues  from the  Program's
reserves and is calculated pursuant to the terms of the Program Agreement.  Such
repurchase offer is recalculated  monthly in order to reflect cash distributions
made to the limited partners and extraordinary  events. The following table sets
forth,  for the  periods  indicated,  Dyco's  repurchase  offer per Unit and the
amount of the Program's  cash  distributions  per Unit for the same period.  For
purposes of this Annual Report,  a Unit  represents an initial  subscription  of
$5,000 to the Program.

                                    Repurchase            Cash
                                       Price          Distributions
                                    ----------        -------------
      1997:
         First Quarter                 $ 50                $ -
         Second Quarter                  50                  -
         Third Quarter                  162                  -
         Fourth Quarter                 162                 25

      1998:
         First Quarter                 $137                $20
         Second Quarter                 117                  -
         Third Quarter                  160                 20
         Fourth Quarter                 140                  -

      1999:
         First Quarter                 $140                $ -

     The Program  has 2,000  Units  outstanding  and  approximately  600 Limited
Partners of record.




                                      -11-
<PAGE>




ITEM 6.     SELECTED FINANCIAL DATA

      Selected Financial Data

     The following table presents selected financial data for the Program.  This
data should be read in conjunction with the financial statements of the Program,
and the respective notes thereto,  included elsewhere in this Annual Report. See
"Item 8. Financial Statements and Supplementary Data."
<TABLE>
<CAPTION>

                                                                   December 31,
                                          --------------------------------------------------------------
                                            1998          1997         1996          1995         1994
                                          --------      --------     --------      --------     --------

<S>                                       <C>           <C>          <C>           <C>          <C>     
Summary of Operations:
   Oil and gas sales                      $135,080      $192,298     $191,618      $134,485     $179,004
   Total revenues                          135,998       193,485      192,842       135,166      180,070

   Lease operating expenses                 33,635        43,348       50,808        58,323       48,015
   Production taxes                          9,879        14,085       13,772         9,521       13,061
   General and administrative
      expenses                              20,576        22,280       21,766        21,713       20,194
   Depreciation, depletion, and
      amortization of oil and gas
      properties                             8,379        16,518        6,950        17,395       32,455

   Net income                               63,529        97,254       99,546        28,214       66,345
      per Unit                               31.43         48.12        49.26         13.96        32.83
   Cash distributions                       80,840        50,525      131,365        40,420      111,155
      per Unit                                  40            25           65            20           55

Summary Balance Sheet Data:
   Total assets                            128,068       149,325      133,084       140,704      142,576
   Partners' capital                       123,962       141,273       94,544       126,363      138,569

</TABLE>


                                      -12-
<PAGE>



ITEM 7.     MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND 
            RESULTS OF OPERATIONS

      Use of Forward-Looking Statements and Estimates

      This Annual Report contains certain forward-looking  statements. The words
"anticipate,"  "believe,"  "expect,"  "plan," "intend,"  "estimate,"  "project,"
"could," "may," and similar expressions are intended to identify forward-looking
statements.  Such statements reflect  management's current views with respect to
future  events and  financial  performance.  This Annual  Report  also  includes
certain information which is, or is based upon, estimates and assumptions.  Such
estimates and assumptions  are  management's  efforts to accurately  reflect the
condition and operation of the Program.

      Use of  forward-looking  statements and estimates and assumptions  involve
risks and uncertainties which include, but are not limited to, the volatility of
oil and gas prices, the uncertainty of reserve  information,  the operating risk
associated with oil and gas properties  (including the risk of personal  injury,
death, property damage, damage to the well or producing reservoir, environmental
contamination,  and other  operating  risks),  the  prospect of changing tax and
regulatory laws, the availability and capacity of processing and  transportation
facilities,  the  general  economic  climate,  the  supply  and price of foreign
imports of oil and gas, the level of consumer product demand,  and the price and
availability  of  alternative  fuels.  Should  one or more  of  these  risks  or
uncertainties  occur  or  should  estimates  or  underlying   assumptions  prove
incorrect,  actual  conditions or results may vary materially and adversely from
those stated, anticipated, believed, estimated, or otherwise indicated.


      General Discussion

      The following  general  discussion  should be read in conjunction with the
analysis of results of operations  provided below.  The most important  variable
affecting the Program's  revenues is the prices received for the sale of oil and
gas. Predicting future prices is not possible.  Concerning past trends,  average
yearly  wellhead gas prices in the United States have been volatile for a number
of years. For the past ten years, such average prices have generally been in the
$1.40 to $2.40 per Mcf range.

      Substantially  all of the  Program's  gas  reserves  are being sold on the
"spot  market."  Prices on the spot  market  are  subject to wide  seasonal  and
regional pricing  fluctuations due to the highly  competitive nature of the spot
market. In addition,  such spot market sales are generally  short-term in nature
and are dependent  upon the  obtaining of  transportation  services  provided by
pipelines. Spot prices for the Program's gas decreased from



                                      -13-
<PAGE>



approximately  $2.32 per Mcf at December 31, 1997 to approximately $1.93 per Mcf
at  December  31,  1998.  Such prices were on an MMBTU basis and differ from the
prices  actually  received by the Program due to  transportation  and  marketing
costs, BTU adjustments,  and regional price and quality  differences.  Continued
very low oil prices as discussed below may cause downward pressure on gas prices
due to some users of gas converting to oil as a cheaper fuel alternative.

      For the past ten years,  average  oil prices  have  generally  been in the
$16.00 to $24.00 per barrel range.  Due to global  consumption and supply trends
over the last year as well as at least a  short-term  slowdown  in Asian  energy
demand,  oil prices  over the past year have  reached  historically  low levels,
dropping to as low as  approximately  $9.00 per barrel.  It is not known whether
this  trend  will  continue.   Prices  for  the  Program's  oil  decreased  from
approximately  $16.25 per barrel at December 31, 1997 to approximately $9.50 per
barrel at December 31, 1998.

      As of February  28, 1999 oil and gas prices were  approximately  $9.50 per
barrel and $1.55 per Mcf, respectively.  Future prices for both oil and gas will
likely  be  different  from  (and may be lower  than)  the  prices  in effect on
December 31, 1998 and February 28, 1999.  As of the date of this Annual  Report,
oil prices have increased  slightly over the February 28, 1999 price,  primarily
due to the March 1999  announcement that several oil producing nations intend to
curtail oil exports.  Management is unable to predict whether future oil and gas
prices will (i) stabilize, (ii) increase, or (iii) decrease.


      Results of Operations


                     Year Ended December 31, 1998 Compared
                        to Year Ended December 31, 1997
                     -------------------------------------

      Total oil and gas sales  decreased  $57,218 (29.8%) in 1998 as compared to
1997.  Of this  decrease,  approximately  $29,000  was  related to a decrease in
volumes of gas sold and  approximately  $26,000 was related to a decrease in the
average price of gas sold.  Volumes of oil and gas sold decreased 41 barrels and
12,359 Mcf,  respectively,  in 1998 as compared to 1997. The decrease in volumes
of gas sold resulted  primarily from a negative  prior period volume  adjustment
made during 1998 by the operator on one well which was sold during 1997. Average
oil  and  gas  prices  decreased  to  $12.98  per  barrel  and  $1.94  per  Mcf,
respectively, in 1998 from $19.87 per barrel and $2.32 per Mcf, respectively, in
1997.

      Oil and gas production  expenses  (including lease operating  expenses and
production  taxes)  decreased  $13,919 (24.2%) in 1998 as compared to 1997. This
decrease resulted primarily from (i) a



                                      -14-
<PAGE>



decrease in production  taxes  associated with the decrease in oil and gas sales
and (ii) workover  expenses incurred in 1997 on one well in order to improve the
recovery of  reserves.  As a  percentage  of oil and gas sales,  these  expenses
increased  to 32.2% in 1998 from 29.9% in 1997.  This  percentage  increase  was
primarily due to the decreases in the average prices of oil and gas sold.

      Depreciation,  depletion,  and  amortization  of oil  and  gas  properties
decreased  $8,139  (49.3%) in 1998 as compared to 1997.  This decrease  resulted
primarily from (i) an upward  revision in the estimate of remaining gas reserves
at  December  31,  1998 and (ii) the  decrease  in  volumes  of gas  sold.  As a
percentage  of oil and gas sales,  this  expense  decreased to 6.2% in 1998 from
8.6% in 1997. This percentage  decrease was primarily due to the dollar decrease
in depreciation, depletion, and amortization.

      General and  administrative  expenses  decreased  $1,704 (7.6%) in 1998 as
compared to 1997. As a percentage of oil and gas sales, these expenses increased
to 15.2% in 1998 from 11.6% in 1997. This percentage  increase was primarily due
to the decrease in oil and gas sales.


                     Year Ended December 31, 1997 Compared
                        to Year Ended December 31, 1996
                     -------------------------------------

      Total oil and gas sales remained  relatively  constant in 1997 as compared
to 1996.  An increase  of  approximately  $16,000  related to an increase in the
average  price  of  gas  sold  was   substantially   offset  by  a  decrease  of
approximately  $15,000 related to a decrease in volumes of gas sold.  Volumes of
oil and gas sold  decreased  2 barrels and 7,272 Mcf,  respectively,  in 1997 as
compared to 1996.  Average oil and gas prices increased to $19.87 per barrel and
$2.32 per Mcf,  respectively,  in 1997 from $19.27 per barrel and $2.12 per Mcf,
respectively, in 1996.

      Oil and gas production  expenses  (including lease operating  expenses and
production  taxes)  decreased  $7,147 (11.1%) in 1997 as compared to 1996.  This
decrease resulted primarily from (i) the decrease in volumes of gas sold in 1997
and (ii) the sale of one high-cost  well in 1997. As a percentage of oil and gas
sales,  these  expenses  decreased  to 29.9% in 1997  from  33.7% in 1996.  This
percentage  decrease was primarily due to the decrease in oil and gas production
expenses.

      Depreciation,  depletion,  and  amortization  of oil  and  gas  properties
increased  $9,568 (137.7%) in 1997 as compared to 1996.  This increase  resulted
primarily from (i) a decrease in the oil and gas prices used in the valuation of
reserves  at December  31,  1997 as  compared  to  December  31, 1996 and (ii) a
$28,000  recompletion  in 1997 which  increased  the  capital  costs  subject to
amortization. As a percentage of oil and gas sales, this expense



                                      -15-
<PAGE>



increased to 8.6% in 1997 as compared to 3.6% in 1996. This percentage  increase
was  primarily  due to the  dollar  increase  in  depreciation,  depletion,  and
amortization.

      General  and  administrative  expenses  increased  $514  (2.4%) in 1997 as
compared to 1996.  As a percentage of oil and gas sales,  this expense  remained
relatively constant at 11.6% in 1997 as compared to 11.4% in 1996.


      Liquidity and Capital Resources

      Net  proceeds  from  operations  less  necessary   operating  capital  are
distributed to the limited  partners on a quarterly  basis.  See "Item 5. Market
for the  Registrant's  Limited  Partnership  Units and Related  Limited  Partner
Matters."  The net proceeds  from  production  are not  reinvested in productive
assets, except to the extent that producing wells are improved, or where methods
are employed to permit more efficient recovery of reserves, thereby resulting in
a positive  economic impact.  Assuming 1998 production  levels for future years,
the  Program's  proved  reserve  quantities  at  December  31,  1998  would have
remaining  lives of  approximately  8.6 years for gas reserves and 3.4 years for
oil reserves.  However,  since the Program's  reserve estimates are based on oil
and gas prices at December 31, 1998, it is possible that a significant  decrease
in oil and gas prices from  December  31, 1998 levels will reduce such  reserves
and their corresponding life-span.

      The Program's  available capital from the limited partners'  subscriptions
has been spent on oil and gas drilling activities and there should be no further
material capital resource commitments in the future.  Occasional expenditures by
the Program for well completions or workovers,  however, may reduce or eliminate
cash available for a particular  quarterly cash  distribution.  During 1997, the
Program invested approximately $28,000 in a recompletion on one well in order to
improve  the  recovery  of  reserves.   The   recompletion   was   unsuccessful.
Subsequently,  the well was sold for salvage value of approximately  $8,300. The
unsuccessful  recompletion  expenses incurred by the Program adversely  impacted
the Program's cash flows during 1997. The Program has no debt commitments.  Cash
for operational purposes will be provided by current oil and gas production.

      There can be no  assurance as to the amount of the  Program's  future cash
distributions.   The  Program's  ability  to  make  cash  distributions  depends
primarily  upon the level of  available  cash flow  generated  by the  Program's
operating  activities,  which will be affected (either positively or negatively)
by many factors  beyond the control of the Program,  including  the price of and
demand for oil and gas and other market and economic conditions.  Even if prices
and costs remain  stable,  the amount of cash available for  distributions  will
decline over time (as the volume



                                      -16-
<PAGE>



of  production  from  producing  properties  declines)  since the Program is not
replacing production through acquisitions of producing properties and drilling.


      Inflation and Changing Prices

      Prices obtained for oil and gas production  depend upon numerous  factors,
including the extent of domestic and foreign production, foreign imports of oil,
market  demand,  domestic  and  foreign  economic  conditions  in  general,  and
governmental  regulations  and tax laws.  The general  level of inflation in the
economy did not have a material effect on the operations of the Program in 1998.
Oil and gas prices have  fluctuated  during recent years and generally  have not
followed  the same pattern as  inflation.  See "Item 2.  Properties  Oil and Gas
Production, Revenue, and Price History."


      Year 2000 Computer Issues

                                   In General

      The Year 2000 Issue ("Y2K")  refers to the inability of computer and other
information  technology  systems to properly process date and time  information,
stemming from the earlier  programming  practice of using two digits rather than
four to  represent  the  year in a date.  For  example,  computer  programs  and
imbedded  chips that are date  sensitive  may recognize a date using (00) as the
year 1900 rather than the year 2000. The consequence of Y2K is that computer and
imbedded  processing  systems  may be at  risk of  malfunctioning,  particularly
during the transition from 1999 to 2000.

      The effects of Y2K are exacerbated by the  interdependence of computer and
telecommunication systems throughout the world. This interdependence also exists
among the Program, Samson, and their vendors,  customers, and business partners,
as well as with  regulators.  The potential risks associated with Y2K for an oil
and gas  production  company  fall into  three  general  areas:  (i)  financial,
leasehold and  administrative  computer systems,  (ii) imbedded systems in field
process control units, and (iii) third party exposures. As discussed below, Dyco
does not believe that these risks will be material to the Program's operations.

      The Program's business is producing oil and gas. The day-to-day production
of the  Program's  oil and gas is not  dependent on computers or equipment  with
imbedded chips. As further  discussed  below,  management  anticipates  that the
Program's daily business activities will not be materially affected by Y2K.

      The Program  relies  on  Samson  to  provide  all of its  operational  and
administrative services on either a direct or



                                      -17-
<PAGE>



indirect basis. Samson is addressing each of the three Y2K areas discussed above
through a readiness process that seeks to:

      1.    increase the awareness of the issue among key employees;
      2.    identify areas of potential risk;
      3.    assess the relative  impact of these  risks and Samson's  ability to
            manage them; and
      4.    remediate these risks on a priority basis wherever possible.

      Samson  Investment  Company's Chief  Financial  Officer is responsible for
communicating  to its  Board  of  Directors  Y2K  actions  and for the  ultimate
implementation of its Y2K plan. He has delegated to Samson Investment  Company's
Senior  Vice   President-Technology   and   Administrative   Services  principal
responsibility for ensuring Y2K compliance within Samson.

      Samson  has  been  planning  for  the  impact  of Y2K  on its  information
technology  systems  since  1993.  As of March 1,  1999,  Samson is in the final
stages of implementation of a Y2K plan, as summarized below:


                      Financial and Administrative Systems

      1. Awareness. Samson has alerted its officers, managers and supervisors of
Y2K  issues  and  asked  them  to  have  their  employees   participate  in  the
identification  of  potential  Y2K risks which might  otherwise  go unnoticed by
higher level  employees  and  officers.  As a result,  awareness of the issue is
considered high.

      2. Risk   Identification.   Samson's   most   significant   financial  and
administrative  systems  exposure is the Y2K status of the  accounting  and land
administration  system used to collect and manage data for  internal  management
decision making and for external  revenue and accounts payable  purposes.  Other
concerns include network hardware and software,  desktop computing  hardware and
software, telecommunications, and office space readiness.

      3. Risk  Assessment.  The failure to identify  and correct a material  Y2K
problem  could  result in  inaccurate  or  untimely  financial  information  for
management  decision-making  or  cash  flow  and  payment  purposes,   including
maintaining oil and gas leases.

      4.  Remediation.  Since 1993, Samson has been upgrading its accounting and
land  administration  software.  Substantially all of the Y2K upgrades have been
completed,  with the remainder  scheduled to be completed during the 2nd quarter
of 1999.  In  addition,  in 1997 and 1998 Samson  replaced  or applied  software
patches to substantially  all of its network and desktop  software  applications
and believes them to be generally Y2K compliant.  Additional patches or software
upgrades will be applied no later



                                      -18-
<PAGE>



than  May 15,  1999 to  complete  this  process.  The  costs  of all  such  risk
assessments and remediation are not expected to be material to the Program.

      5. Contingency  Planning.  Notwithstanding the foregoing,  should there be
significant  unanticipated  disruptions in Samson's financial and administrative
systems,  all of the accounting processes that are currently automated will need
to be performed  manually.  Samson will  consider in the second half of 1999 its
options with  respect to  contingency  arrangements  for  temporary  staffing to
accommodate such situations.


                                Imbedded Systems

      1. Awareness.  Samson's  Y2K  program  has  involved  all  levels of field
personnel  from  production  foremen and higher.  Employees at all levels of the
organization  have been asked to participate in the  identification of potential
Y2K risks,  which might  otherwise go unnoticed  by higher level  employees  and
officers of Samson, and as a result, awareness of the issue is considered high.

      2. Risk  Identification.  Samson has inventoried all possible exposures to
imbedded  chips and systems.  Such exposures can be classified as either (i) oil
and gas  production  and  processing  equipment or (ii) office  machines such as
faxes, copiers, phones, etc.

      With respect to oil and gas production and processing  equipment,  neither
Samson nor the Program operate offshore wells, significant processing plants, or
wells with older electronic monitoring systems. As a result,  Samson's inventory
identified less than 10 applications  using imbedded chips.  All of these are in
the process of being tested by the respective vendors and are expected to be Y2K
compliant or replaced no later than May 30, 1999. Oil and gas production related
to such equipment is very minor with respect to the entire Samson group, and, in
fact, the Program's production may not use such equipment at all.

      Office  machines are currently  being tested by Samson and vendors.  It is
expected that such machines will be made compliant or replaced no later than May
15, 1999.

      3. Risk Assessment and Remediation.  The failure to identify and correct a
material Y2K problem in an imbedded system could result in outcomes ranging from
errors in data reporting to  curtailments  or shutdowns in production.  As noted
above,  Samson has identified less than 10 imbedded system applications that may
have a Y2K problem.  None of these  applications  are believed to be material to
Samson or the Program. Once identified, assessed and prioritized, Samson intends
to test and upgrade  imbedded  components  and systems in field process  control
units deemed to pose the greatest risk of significant non-compliance and capable



                                      -19-
<PAGE>



of testing.  Samson believes that sufficient  manual  processes are available to
minimize any such field level risk and that there will be no material  impact on
the Program with respect to these applications.

      4. Contingency Planning. Should material production disruptions occur as a
result of Y2K  failures in field  operations,  Samson will  utilize its existing
field  personnel  in an attempt to avoid any material  impact on operating  cash
flow.  Samson is not able to  quantify  any  potential  exposure in the event of
systems failure or inadequate manual alternatives.


                              Third Party Exposures

      1. Awareness.  Samson has advised  management to consider Y2K implications
with its outside vendors, customers, and business partners.  Management has been
asked to participate in the  identification  of potential  third party Y2K risks
and, as a result, awareness of the issue is considered high.

      2. Risk Identification. Samson's most significant third party Y2K exposure
is its  dependence on third parties for the receipt of revenues from oil and gas
sales.   However,   virtually  all  of  these  purchasers  are  very  large  and
sophisticated companies. Other Y2K concerns include the availability of electric
power to Samson's field operations,  the integrity of telecommunication systems,
and the readiness of commercial banks to execute electronic fund transfers.

      3. Risk  Assessment.  Because of the high  awareness of the Y2K problem in
the U.S.,  Samson has not  undertaken  and does not plan to  undertake  a formal
company  wide plan to make  inquiries  of third  parties  on the  subject of Y2K
readiness.  If it did so,  Samson has no ability  to require  responses  to such
inquiries  or to  independently  verify  their  accuracy.  Samson has,  however,
received oral  assurances  from its  significant  oil and gas  purchasers of Y2K
compliance.  If significant  disruptions  from major  purchasers  were to occur,
however,  there could be a material and adverse impact on the Program's  results
of operations, liquidity, and financial conditions.

      It is  important  to note that  third  party oil and gas  purchasers  have
significant  incentives  to avoid  disruptions  arising from a Y2K failure.  For
example, most of these parties are under contractual obligations to purchase oil
and gas or  disperse  revenues  to Samson.  The  failure to do so will result in
contractual  and  statutory  penalties.  Therefore,  Dyco  believes  that  it is
unlikely that there will be material  third party  non-compliance  with purchase
and remittance obligations as a result of Y2K issues.

      4.   Remediation.   Where  Samson   perceives   significant  risk  of  Y2K
non-compliance that may have a material impact on it, and



                                      -20-
<PAGE>



where the  relationship  between  Samson  and a vendor,  customer,  or  business
partner permits, joint testing may be undertaken during 1999 to further identify
these risks.

      5. Contingency  Planning.  In the unlikely event that material  production
disruptions  occur as a result of Y2K failures of third  parties,  the Program's
operating cash flow could be impacted.  This  contingency  will be factored into
deliberations on the level of quarterly cash  distributions  paid out during any
such period of cash flow disruption.


ITEM 7A.    QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET
            RISK.

      The Program does not hold any market risk sensitive instruments.





                                      -21-
<PAGE>



ITEM 8.     FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA



      REPORT OF INDEPENDENT ACCOUNTANTS



TO THE PARTNERS

DYCO OIL AND GAS PROGRAM 1986-X LIMITED PARTNERSHIP


      In our opinion, the accompanying balance sheets and the related statements
of operations,  changes in partners'  capital and cash flows present fairly,  in
all material  respects,  the financial  position of the Dyco Oil and Gas Program
1986-X Limited  Partnership,  a Minnesota limited  partnership,  at December 31,
1998 and 1997,  and the results of its operations and its cash flows for each of
the three years in the period  ended  December  31,  1998,  in  conformity  with
generally accepted  accounting  principles.  These financial  statements are the
responsibility of the Program's management;  our responsibility is to express an
opinion on these  financial  statements  based on our audits.  We conducted  our
audits of these  financial  statements in  accordance  with  generally  accepted
auditing  standards  which  require that we plan and perform the audit to obtain
reasonable assurance about whether the financial statements are free of material
misstatement.  An audit includes examining, on a test basis, evidence supporting
the  amounts  and  disclosures  in  the  financial  statements,   assessing  the
accounting  principles  used and significant  estimates made by management,  and
evaluating the overall  financial  statement  presentation.  We believe that our
audits provide a reasonable basis for the opinion expressed above.





                                    PricewaterhouseCoopers LLP








Tulsa, Oklahoma
March 22, 1999



                                      -22-
<PAGE>



                           DYCO OIL AND GAS PROGRAM
                          1986-X LIMITED PARTNERSHIP
                                Balance Sheets
                          December 31, 1998 and 1997

                                    ASSETS
                                    ------
                                                       1998           1997
                                                     --------       --------

CURRENT ASSETS:
   Cash and cash equivalents                         $ 29,249       $ 21,256
   Accrued oil and gas sales                           15,885         34,977
                                                      -------        -------

      Total current assets                           $ 45,134       $ 56,233

NET OIL AND GAS PROPERTIES, utilizing
   the full cost method                                71,519         79,898

DEFERRED CHARGE                                        11,415         13,194
                                                      -------        -------

                                                     $128,068       $149,325
                                                      =======        =======

                       LIABILITIES AND PARTNERS' CAPITAL
                       ---------------------------------

CURRENT LIABILITIES:
   Accounts payable                                  $  2,107       $  2,637
                                                      -------        -------
      Total current liabilities                      $  2,107       $  2,637

ACCRUED LIABILITY                                    $  1,999       $  5,415

PARTNERS' CAPITAL:
   General Partner, 21 general
       partner units                                 $  1,239       $  1,412
   Limited Partners, issued and
      outstanding, 2,000 Units                        122,723        139,861
                                                      -------        -------
      Total Partners' capital                        $123,962       $141,273
                                                      -------        -------

                                                     $128,068       $149,325
                                                      =======        =======



              The accompanying notes are an integral part of these
                              financial statements.




                                      -23-
<PAGE>




                           DYCO OIL AND GAS PROGRAM
                          1986-X LIMITED PARTNERSHIP
                           Statements of Operations
             For the Years Ended December 31, 1998, 1997, and 1996


                                              1998        1997        1996
                                            --------    --------    --------

REVENUES:
   Oil and gas sales                        $135,080    $192,298    $191,618
   Interest                                      918       1,187       1,224
                                             -------     -------     -------

                                            $135,998    $193,485    $192,842

COSTS AND EXPENSES:
   Lease operating                          $ 33,635    $ 43,348    $ 50,808
   Production taxes                            9,879      14,085      13,772
   Depreciation, depletion, and
      amortization of oil and gas
      properties                               8,379      16,518       6,950
   General and administrative                 20,576      22,280      21,766
                                             -------     -------     -------

                                            $ 72,469    $ 96,231    $ 93,296
                                             -------     -------     -------

NET INCOME                                  $ 63,529    $ 97,254    $ 99,546
                                             =======     =======     =======

GENERAL PARTNER (1%) - NET INCOME           $    635    $    973    $    995
                                             =======     =======     =======

LIMITED PARTNERS (99%) - NET INCOME         $ 62,894    $ 96,281    $ 98,551
                                             =======     =======     =======

NET INCOME per Unit                         $  31.43    $  48.12    $  49.26
                                             =======     =======     =======

UNITS OUTSTANDING                              2,021       2,021       2,021
                                             =======     =======     =======

              The accompanying notes are an integral part of these
                              financial statements.




                                      -24-
<PAGE>




                           DYCO OIL AND GAS PROGRAM
                          1986-X LIMITED PARTNERSHIP
                  Statements of Changes in Partners' Capital 
             For the Years Ended December 31, 1998, 1997, and 1996


                                       General      Limited
                                       Partner      Partners         Total
                                      --------     ----------     ----------

Balances at Dec. 31, 1995              $1,263       $125,100       $126,363
   Cash distributions                 ( 1,314)     ( 130,051)     ( 131,365)
   Net income                             995         98,551         99,546
                                        -----        -------        -------

Balances at Dec. 31, 1996              $  944       $ 93,600       $ 94,544
   Cash distributions                 (   505)     (  50,020)     (  50,525)
   Net income                             973         96,281         97,254
                                        -----        -------        -------

Balances at Dec. 31, 1997              $1,412       $139,861       $141,273
   Cash distributions                 (   808)     (  80,032)     (  80,840)
   Net income                             635         62,894         63,529
                                        -----        -------        -------

Balances at Dec. 31, 1998              $1,239       $122,723       $123,962
                                        =====        =======        =======


              The accompanying notes are an integral part of these
                              financial statements.




                                      -25-
<PAGE>




                            DYCO OIL AND GAS PROGRAM
                           1986-X LIMITED PARTNERSHIP
                            Statements of Cash Flows
              For the Years Ended December 31, 1998, 1997, and 1996

                                            1998          1997           1996
                                         ---------     ----------     ---------
CASH FLOWS FROM OPERATING ACTIVITIES:
   Net income                             $63,529       $97,254        $ 99,546
   Adjustments to reconcile net
      income to net cash provided
      by operating activities:
      Depreciation, depletion, and
         amortization of oil and gas
         properties                         8,379        16,518           6,950
      (Increase) decrease in accrued
         oil and gas sales                 19,092         5,828       (  15,120)
      (Increase) decrease in
         deferred charge                    1,779      (    172)            934
      Increase (decrease) in
         accounts payable                (    530)     ( 26,761)         24,776
      Decrease in accrued liability      (  3,416)     (  3,727)      (     577)
                                           ------        ------         -------
   Net cash provided by operating
      activities                          $88,833       $88,940        $116,509
                                           ------        ------         -------

CASH FLOWS FROM INVESTING ACTIVITIES:
   Proceeds from sale of oil and
      gas properties                      $  -          $ 8,846        $  4,991
   Additions to oil and gas properties       -         ( 34,801)           -
                                           ------        ------         -------

   Net cash provided (used) by
      investing activities                $  -         ($25,955)       $  4,991
                                           ------        ------         -------

CASH FLOWS FROM FINANCING ACTIVITIES:
   Cash distributions                    ($80,840)     ($50,525)      ($131,365)
                                           ------        ------         -------

   Net cash used by financing
      activities                         ($80,840)     ($50,525)      ($131,365)
                                           ------        ------         -------
NET INCREASE (DECREASE) IN CASH
   AND CASH EQUIVALENTS                   $ 7,993       $12,460       ($  9,865)

CASH AND CASH EQUIVALENTS AT
   BEGINNING OF PERIOD                     21,256         8,796          18,661
                                           ------        ------         -------
CASH AND CASH EQUIVALENTS AT
   END OF PERIOD                          $29,249       $21,256        $  8,796
                                           ======        ======         =======

                     The accompanying notes are an integral
                       part of these financial statements.




                                      -26-
<PAGE>




              DYCO OIL AND GAS PROGRAM 1986-X LIMITED PARTNERSHIP
                         Notes to Financial Statements
             For the Years Ended December 31, 1998, 1997, and 1996


1.    ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      Organization and Nature of Operations

            The  Dyco  Oil and  Gas  Program  1986-X  Limited  Partnership  (the
      "Program"),  a Minnesota  limited  partnership,  commenced  operations  on
      December  12, 1986.  Dyco  Petroleum  Corporation  ("Dyco") is the General
      Partner  of the  Program.  Affiliates  of Dyco  owned 676  (33.8%)  of the
      Program's Units at December 31, 1998.

            The Program's sole business is the development and production of oil
      and gas with a concentration  on gas.  Substantially  all of the Program's
      gas reserves are being sold  regionally  in the "spot  market." Due to the
      highly  competitive  nature of the spot market,  prices on the spot market
      are  subject  to wide  seasonal  and  regional  pricing  fluctuations.  In
      addition,  such spot market sales are  generally  short-term in nature and
      are dependent upon the obtaining of  transportation  services  provided by
      pipelines.  The prices  received for the Program's oil and gas are subject
      to influences such as global consumption and supply trends.


      Cash and Cash Equivalents

            The Program considers all highly liquid  investments with a maturity
      of three  months  or less  when  purchased  to be cash  equivalents.  Cash
      equivalents  are not  insured,  which  cause the  Program to be subject to
      risk.


      Credit Risk

            Accrued  oil and gas sales  which are due from a variety  of oil and
      gas purchasers subject the Program to a concentration of credit risk. Some
      of these purchasers are discussed in Note 3 - Major Customers.


      Oil and Gas Properties

            Oil and gas  operations are accounted for using the full cost method
      of accounting. All productive and non-productive costs associated with the
      acquisition,  exploration,  and  development  of oil and gas  reserves are
      capitalized.  During 1997, the Program invested approximately $28,000 in a
      recompletion on one well in order



                                      -27-
<PAGE>



      to improve the recovery of reserves.  The recompletion  was  unsuccessful.
      Subsequently, the well was sold for salvage value of approximately $8,300.
      Capitalized costs are depleted on the gross revenue method using estimates
      of proved reserves. The full cost amortization rates per equivalent Mcf of
      gas produced during the years ended December 31, 1998, 1997, and 1996 were
      $0.12,  $0.20,  and $0.08,  respectively.  The  Program's  calculation  of
      depreciation,   depletion,  and  amortization  includes  estimated  future
      expenditures  to be incurred in developing  proved  reserves and estimated
      dismantlement  and abandonment  costs, net of estimated salvage values. In
      the event the unamortized  cost of oil and gas properties  being amortized
      exceeds the full cost ceiling (as defined by the  Securities  and Exchange
      Commission  ("SEC"))  the excess is charged to expense in the year  during
      which  such  excess  occurs.  Sales and  abandonments  of  properties  are
      accounted for as  adjustments  of  capitalized  costs with no gain or loss
      recognized,   unless  such  adjustments  would   significantly  alter  the
      relationship between capitalized costs and proved oil and gas reserves.


      Deferred Charge

            The Deferred Charge at December 31, 1998 and 1997  represents  costs
      deferred for lease  operating  expenses  incurred in  connection  with the
      Program's  underproduced  gas  imbalance  positions.   The  rate  used  in
      calculating  the deferred  charge is the average of the annual  production
      costs per Mcf. At December 31, 1998,  cumulative  total gas sales  volumes
      for  underproduced  wells were less than the Program's  pro-rata  share of
      total gas production from these wells by 22,631 Mcf,  resulting in prepaid
      lease  operating  expenses of $11,415.  At December 31,  1997,  cumulative
      total  gas  sales  volumes  for  underproduced  wells  were  less than the
      Program's  pro-rata  share of total gas  production  from  these  wells by
      22,748 Mcf, resulting in prepaid lease operating expenses of $13,194.


      Accrued Liability

            The  Accrued  Liability  at December  31,  1998 and 1997  represents
      charges accrued for lease operating  expenses  incurred in connection with
      the  Program's  overproduced  gas  imbalance  positions.  The rate used in
      calculating the accrued  liability is the average of the annual production
      costs per Mcf. At December 31, 1998,  cumulative  total gas sales  volumes
      for overproduced  wells exceeded the Program's pro-rata share of total gas
      production  from these  wells by 3,964  Mcf,  resulting  in accrued  lease
      operating  expenses of $1,999. At December 31, 1997,  cumulative total gas
      sales volumes for overproduced wells exceeded the Program's pro-



                                      -28-
<PAGE>



      rata  share  of total  gas  production  from  these  wells  by 9,336  Mcf,
      resulting in accrued lease operating expenses of $5,415.


      Oil and Gas Sales

            The Program's oil and condensate  production is sold,  title passed,
      and revenue  recognized  at or near the Program's  wells under  short-term
      purchase  contracts at prevailing  prices in accordance with  arrangements
      which are  customary in the oil industry.  Sales of gas  applicable to the
      Program's  interest in producing oil and gas leases are recorded as income
      when the gas is metered  and title  transferred  pursuant to the gas sales
      contracts  covering the Program's  interest in gas  reserves.  During such
      times as the  Program's  sales of gas exceed its pro rata  ownership  in a
      well,  such sales are recorded as income  unless total sales from the well
      have  exceeded  the  Program's  share  of  estimated  total  gas  reserves
      underlying  the  property  at which  time  such  excess is  recorded  as a
      liability. At December 31, 1998 and 1997, no such liability was recorded.


      Use of Estimates in Financial Statements

            The preparation of financial statements in conformity with generally
      accepted  accounting  principles requires management to make estimates and
      assumptions that affect the reported amounts of assets and liabilities and
      disclosure  of  contingent  assets  and  liabilities  at the  date  of the
      financial  statements  and the  reported  amounts of revenues and expenses
      during the  reporting  period.  Actual  results  could  differ  from those
      estimates.  Further, the deferred charge and the accrued liability involve
      estimates which could materially differ from the actual amounts ultimately
      realized or incurred in the near term.  Oil and gas reserves  (see Note 4)
      also involve significant  estimates which could materially differ from the
      actual amounts ultimately realized.


      Income Taxes

            Income or loss for income tax purposes is  includable  in the income
      tax returns of the partners. Accordingly, no recognition has been given to
      income taxes in the accompanying financial statements.




                                      -29-
<PAGE>



2.    TRANSACTIONS WITH RELATED PARTIES

            Under  the  terms of the  Program  Agreement,  Dyco is  entitled  to
      receive  a   reimbursement   for  all  direct  expenses  and  general  and
      administrative,  geological,  and engineering expenses it incurs on behalf
      of the Program.  During the years ended December 31, 1998, 1997, and 1996,
      such expenses  totaled $20,576,  $22,280,  and $21,766,  respectively,  of
      which $16,080 was paid each year to Dyco and its affiliates.

            Affiliates  of  the  Program   operate   certain  of  the  Program's
      properties.  Their policy is to bill the Program for all customary charges
      and cost  reimbursements  associated with these activities,  together with
      any  compressor  rentals,  consulting,  or other services  provided.  Such
      charges are  comparable to third party charges in the area where the wells
      are located and are the same as charged to other working  interest  owners
      in the wells.


3.    MAJOR CUSTOMERS

            The following  purchaser  individually  accounted for 10% or more of
      the  combined  oil and gas  revenues  of the  Program  for the years ended
      December 31, 1998, 1997, and 1996:

            Purchaser               1998        1997        1996
            -------------           -----       -----       -----

            El Paso Energy
              Marketing Company     86.9%       85.4%       85.8%
            Transok, Inc.           10.5%       11.9%         - %

            In the  event of  interruption  of  purchases  by these  significant
       customers  or  the  cessation  or  material  change  in  availability  of
       open-access  transportation by the Program's pipeline  transporters,  the
       Program may encounter  difficulty in marketing its gas and in maintaining
       historic sales levels.  Alternative purchasers or transporters may not be
       readily available.




                                      -30-
<PAGE>




4.    SUPPLEMENTAL OIL AND GAS INFORMATION

            The  following  supplemental  information  regarding the oil and gas
      activities  of  the  Program  is  presented  pursuant  to  the  disclosure
      requirements promulgated by the SEC.


      Capitalized Costs

            The  Program's  capitalized  costs  and  accumulated   depreciation,
      depletion,  amortization, and valuation allowance at December 31, 1998 and
      1997 were as follows:


                                                       December 31,
                                               ---------------------------
                                                  1998             1997
                                               ----------       ----------

      Proved properties                        $9,214,142       $9,214,142

      Less accumulated depreciation,
         depletion, amortization, and
         valuation allowance                  ( 9,142,623)     ( 9,134,244)
                                                ---------        ---------

      Net oil and gas properties               $   71,519       $   79,898
                                                =========        =========


      Costs Incurred

            The  Program  incurred  no  oil  and  gas  property  acquisition  or
      exploration  costs  during 1998,  1997,  and 1996.  Costs  incurred by the
      Program in connection with its oil and gas property development activities
      during 1998, 1997, and 1996 were as follows:


                                                   December 31,
                                           -----------------------------
                                           1998         1997        1996
                                           ----       -------       ----

      Development costs                    $ -        $34,801       $ -
                                            ===        ======        ===



                                      -31-
<PAGE>



Quantities of Proved Oil and Gas Reserves - Unaudited

      Set forth below is a summary of the changes in the net  quantities  of the
Program's  proved oil and gas  reserves  for the years ended  December 31, 1998,
1997, and 1996. Proved reserves were estimated by petroleum  engineers  employed
by affiliates of Dyco.  All of the Program's  reserves are located in the United
States and there are no proved undeveloped  reserves.  The following information
includes certain gas balancing adjustments which cause the gas volumes to differ
from the reserve information prepared by Dyco.

<TABLE>
<CAPTION>

                                       1998                       1997                     1996
                                ---------------------    ---------------------      ---------------------
                                  Oil          Gas         Oil          Gas           Oil         Gas
                                (Bbls)        (Mcf)      (Bbls)        (Mcf)        (Bbls)       (Mcf)
                                -------     ---------    -------     ---------      -------     ---------
<S>                             <C>         <C>          <C>         <C>            <C>        <C>    
Proved reserves,
   beginning of year             1,294       405,846      1,333       526,455        1,114      316,119

Revisions of previous
   Estimates                    (  125)      242,797        266      ( 40,347)         526      290,838

Sales of reserves                 -           -            -             -            -           7,032

Production                      (  264)     ( 67,903)    (  305)     ( 80,262)      (  307)    ( 87,534)
                                 -----       -------      -----       -------        -----      -------

Proved reserves,
   end of year                     905       580,740      1,294       405,846        1,333      526,455
                                 =====       =======      =====       =======        =====      =======

Proved developed reserves:
   Beginning of year             1,294       405,846      1,333       526,455        1,114      316,119
                                 -----       -------      -----       -------        -----      -------
   End of year                     905       580,740      1,294       405,846        1,333      526,455
                                 =====       =======      =====       =======        =====      =======
</TABLE>




                                      -32-
<PAGE>




            The process of estimating oil and gas reserves is complex, requiring
      significant   subjective   decisions  in  the   evaluation   of  available
      geological,  engineering,  and economic data for each reservoir.  The data
      for a given reservoir may change  substantially  over time as a result of,
      among other things,  additional development activity,  production history,
      and  viability  of   production   under   varying   economic   conditions;
      consequently,  it  is  reasonably  possible  that  material  revisions  to
      existing  reserve  estimates may occur in the near future.  Although every
      reasonable  effort  has been made to  ensure  that the  reserve  estimates
      reported  herein  represent the most  accurate  assessment  possible,  the
      significance  of  the  subjective  decisions  required  and  variances  in
      available data for various reservoirs make these estimates  generally less
      precise  than other  estimates  presented  in  connection  with  financial
      statement disclosures.  The Program's reserves were determined at December
      31,  1998  using oil and gas prices of $9.50 per barrel and $2.03 per Mcf,
      respectively.


ITEM 9.     CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING  
            AND FINANCIAL DISCLOSURE

      None.

                                    PART III

ITEM 10.    DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

      The Program is a limited  partnership  and has no  directors  or executive
officers.  The following  individuals  are  directors and executive  officers of
Dyco, the General Partner.  The business address of such directors and executive
officers is Two West Second Street, Tulsa, Oklahoma 74103.

            NAME              AGE            POSITION WITH DYCO
      ----------------        ---     --------------------------------

      Dennis R. Neill          47     President and Director

      Patrick M. Hall          40     Chief Financial Officer

      Judy K. Fox              48     Secretary

      The  director   will  hold  office  until  the  next  annual   meeting  of
shareholders  of Dyco  and  until  his  successor  has  been  duly  elected  and
qualified.  All  executive  officers  serve at the  discretion  of the  Board of
Directors.

      Dennis R. Neill joined Samson in 1981, was named Senior Vice President and
Director of Dyco on June 18, 1991,  and was named  President of Dyco on June 30,
1996. Prior to joining Samson,  he was associated with a Tulsa law firm,  Conner
and Winters, where



                                      -33-
<PAGE>



his  principal  practice was in the  securities  area. He received a Bachelor of
Arts degree in political  science from  Oklahoma  State  University  and a Juris
Doctorate  degree from the University of Texas.  Mr. Neill also serves as Senior
Vice  President of Samson  Investment  Company and as President  and Director of
Samson Properties Incorporated,  Samson Hydrocarbons Company, Berry Gas Company,
Circle L Drilling Company,  Compression,  Inc., and Geodyne Resources,  Inc. and
its subsidiaries.

      Patrick M. Hall joined Samson in 1983,  was named a Vice President of Dyco
on June 18,  1991,  and was named  Chief  Financial  Officer of Dyco on June 30,
1996. Prior to joining Samson he was a senior  accountant with Peat Marwick Main
& Co. in Tulsa.  He holds a  Bachelor  of  Science  degree  in  accounting  from
Oklahoma State  University and is a Certified Public  Accountant.  Mr. Hall also
serves as Senior Vice President - Controller of Samson Investment Company.

      Judy K. Fox joined Samson in 1990 and was named  Secretary of Dyco on June
30, 1996.  Prior to joining Samson,  she served as Gas Contract  Manager for Ely
Energy  Company.  Ms.  Fox is also  Secretary  of Berry  Gas  Company,  Circle L
Drilling  Company,  Compression,   Inc.,  Samson  Hydrocarbons  Company,  Samson
Properties Incorporated, and Geodyne Resources, Inc.
and its subsidiaries.

      Section 16(a) Beneficial Ownership Reporting Compliance

      To the best  knowledge  of the Program and Dyco,  there were no  officers,
directors,  or ten  percent  owners who were  delinquent  filers  during 1998 of
reports required under Section 16(a) of the Securities and Exchange Act of 1934.


ITEM 11.    EXECUTIVE COMPENSATION

      The Program is a limited  partnership and,  therefore,  has no officers or
directors.  The following  table  summarizes  the amounts paid by the Program as
compensation and  reimbursements  to Dyco and its affiliates for the three years
ended December 31, 1998:



                                      -34-
<PAGE>



              Compensation/Reimbursement to Dyco and its affiliates
                       Three Years Ended December 31, 1998

Type of Compensation/Reimbursement (1)                    Expense
--------------------------------------          ----------------------------
                                                 1998       1997      1996
                                                -------    -------   -------
Compensation:
   Operations                                     (2)        (2)       (2)

Reimbursements:
   General and Administrative,
      Geological, and Engineering
      Expenses and Direct
      Expenses(3)                               $16,080    $16,080   $16,080

----------
(1)   The  authority  for  all of such  compensation  and  reimbursement  is the
      Program Agreement.  With respect to the Operations activities noted in the
      table, management believes that such compensation is equal to or less than
      that  charged by  unaffiliated  persons in the same  geographic  areas and
      under the same conditions.
(2)   Affiliates of the Program  serve as operator of a substantial  majority of
      the  Program's  wells.  Dyco,  as  General  Partner,  contracts  with such
      affiliates  for  services  as  operator of the wells.  As  operator,  such
      affiliates are  compensated at rates provided in the operating  agreements
      in effect and charged to all parties to such agreement.  The dollar amount
      of such  compensation paid by the Program to such affiliates is impossible
      to quantify as of the date of this Annual Report.
(3)   The  Program  reimburses  Dyco  and  its  affiliates  for  reasonable  and
      necessary general and administrative, geological, and engineering expenses
      and direct  expenses  incurred in  connection  with their  management  and
      operation of the Program. The directors,  officers,  and employees of Dyco
      and its  affiliates  receive no direct  remuneration  from the Program for
      their services to the Program. See "Salary Reimbursement Table" below. The
      allocable general and administrative, geological, and engineering expenses
      are apportioned on a reasonable  basis between the Program's  business and
      all other oil and gas  activities  of Dyco and its  affiliates,  including
      Dyco's  management  and  operation  of  affiliated  oil  and  gas  limited
      partnerships. The allocation to the Program of these costs is made by Dyco
      as General Partner.


      As noted in the  Compensation/Reimbursement  Table above,  the  directors,
officers,  and  employees  of  Dyco  and  their  affiliates  receive  no  direct
remuneration  from the Program for their services.  However,  to the extent such
services  represent direct  involvement with the Program,  as opposed to general
corporate




                                      -35-
<PAGE>




functions,  such  persons'  salaries  are  allocated  to and  reimbursed  by the
Program.   Such  allocation  to  the  Program's   general  and   administrative,
geological, and engineering expenses of the salaries of directors, officers, and
employees of Dyco and its affiliates is based on internal records  maintained by
Dyco and its affiliates,  and represents investor relations,  legal, accounting,
data  processing,   management,  gas  marketing  and  other  functions  directly
attributable  to the Program's  operations.  The following  table  indicates the
approximate   amount  of  general  and  administrative   expense   reimbursement
attributable to the salaries of the directors,  officers,  and employees of Dyco
and its affiliates for the three years ended December 31, 1998:



                                      -36-
<PAGE>
<TABLE>
<CAPTION>



                                                  Salary Reimbursement

                                           Three Years Ended December 31, 1998

                                                                         Long Term Compensation                   
                                                                     ------------------------------               
                                      Annual Compensation                   Awards          Payouts               
                               ---------------------------------     ---------------------  -------               
                                                                                                                
                                                                                   Securi-                        
                                                         Other                       ties                All      
    Name                                                 Annual      Restricted     Under-              Other     
    and                                                  Compen-       Stock        lying     LTIP      Compen-   
 Principal                     Salary         Bonus      sation       Award(s)     Options/  Payouts    sation    
  Position            Year       ($)           ($)         ($)          ($)        SARs(#)     ($)        ($)     
---------------       ----     -------       -------     -------     ----------    --------  -------    -------   
<S>                  <C>       <C>              <C>        <C>           <C>          <C>       <C>        <C>      

C. Philip
Tholen,
President,
Chief Executive
Officer(1)(2)        1996        -               -         -             -            -         -          - 
                                                                                                             
Dennis R. Neill,                                                                                             
President(2)(3)      1996        -               -         -             -            -         -          - 
                     1997        -               -         -             -            -         -          - 
                     1998        -               -         -             -            -         -          - 
All Executive                                                                                                
Officers,                                                                                                    
Directors,                                                                                                   
and Employees                                                                                                
as a group(4)        1996      $9,407            -         -             -            -         -          - 
                     1997      $9,606            -         -             -            -         -          - 
                     1998      $9,516            -         -             -            -         -          - 
----------                                                                                                 
(1)   Mr. Tholen served as President and Chief  Executive  Officer of Dyco until
      June 30, 1996.
(2)   The general and  administrative  expenses  paid by the  Program  and  attributable  to
      salary reimbursements do not include any salary or other compensation  attributable to
      Mr. Tholen or Mr. Neill.
(3)   Mr. Neill became President of Dyco on June 30, 1996.
(4)   No  officer  or  director  of Dyco or its  affiliates  provides  full-time
      services to the Program and no individual's  salary or other  compensation
      reimbursement from the Program equals or exceeds $100,000 per annum.

</TABLE>


                                      -37-
<PAGE>



      Samson  maintains  necessary  inventories of new and used field equipment.
Samson may have provided  some of this  equipment for wells in which the Program
has an interest. This equipment was provided at prices or rates equal to or less
than  those  normally  charged  in the  same or  comparable  geographic  area by
unaffiliated  persons or companies  dealing at arm's  length.  The  operators of
these  wells  bill the  Program  for a  portion  of such  costs  based  upon the
Program's interest in the well.


ITEM 12.    SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

      The following table provides information as to the beneficial ownership of
the Program's Units as of March 1, 1999 by each beneficial owner of more than 5%
of  the  issued  and  outstanding  Units  and by the  directors,  officers,  and
affiliates  of Dyco.  The address of each of such persons is Samson  Plaza,  Two
West Second Street, Tulsa, Oklahoma 74103.


                                                Number of Units
                                                 Beneficially
                                                Owned (Percent
             Beneficial Owner                   of Outstanding)
      -------------------------------           ---------------

      Samson Resources Company                  676      (33.8%)

      All directors, officers, and
         affiliates of Dyco as a group
         and Dyco (5 persons)                   676      (33.8%)


ITEM 13.    CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

      Certain affiliates of Dyco engage in oil and gas activities  independently
of the Program  which  result in  conflicts  of interest  that cannot be totally
eliminated.  The allocation of acquisition  and drilling  opportunities  and the
nature of the compensation  arrangements between the Program and such affiliates
also create potential conflicts of interest.  An affiliate of the Program owns a
significant  amount of the  Program's  Units and  therefore  has an  identity of
interest  with other  limited  partners  with respect to the  operations  of the
Program.

      In order to attempt to assure  limited  liability for limited  partners as
well as an orderly  conduct of business,  management of the Program is exercised
solely by Dyco. The Program Agreement grants Dyco broad discretionary  authority
with  respect  to  the  Program's   participation  in  drilling   prospects  and
expenditure and control of funds,  including  borrowings.  These  provisions are
similar to those contained in prospectuses and partnership  agreements for other
public oil and gas partnerships. Broad



                                      -38-
<PAGE>



discretion as to general management of the Program involves  circumstances where
Dyco has conflicts of interest and where it must allocate costs and expenses, or
opportunities, among the Program and other competing interests.

      Dyco does not devote all of its time, efforts,  and personnel  exclusively
to the  Program.  Furthermore,  the  Program  does not have any  employees,  but
instead relies on the personnel of Samson. The Program thus competes with Samson
(including  other  oil and gas  programs)  for the  time and  resources  of such
personnel.  Samson  devotes  such time and  personnel to the  management  of the
Program as are indicated by the  circumstances and as are consistent with Dyco's
fiduciary duties.

      Affiliates  of the Program  are solely  responsible  for the  negotiation,
administration,  and  enforcement of oil and gas sales  agreements  covering the
Program's  leasehold  interests.  Because  affiliates of the Program who provide
services to the  Program  have  fiduciary  or other  duties to other  members of
Samson,  contract  amendments and  negotiating  positions taken by them in their
effort to enforce  contracts with purchasers may not  necessarily  represent the
positions that the Program would take if it were to administer its own contracts
without involvement with other members of Samson. On the other hand,  management
believes that the Program's  negotiating strength and contractual positions have
been enhanced by virtue of its affiliation with Samson.

      Samson  Resources  Company,  an  affiliate  of  Dyco,  ("Resources")  owns
approximately  34% of the Program's  outstanding  Units as of March 1, 1999. The
Program Agreement permits Resources to independently vote its Units.  Resources'
significant  Unit ownership will therefore  likely  determine the outcome of any
matter submitted for a vote of the Limited Partners.




                                      -39-
<PAGE>






                                    PART IV


ITEM 14.    EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K

      (a)   Financial Statements, Financial Statement Schedules, and Exhibits.

            (1)   Financial  Statements:  The following financial statements for
                  the Program as of December 31, 1998 and 1997 and for the years
                  ended  December 31, 1998,  1997, and 1996 are filed as part of
                  this report:

                        Report of Independent Accountants
                        Balance Sheets
                        Statements of Operations
                        Statements of Changes in Partners' Capital
                        Statements of Cash Flows
                        Notes to Financial Statements

            (2)   Financial Statement Schedules:

                        None.

            (3) Exhibits:

                  4.1   Drilling  Agreement  dated  November  25,  1986 for Dyco
                        Drilling Program 1986-X, a Limited  Partnership,  by and
                        between  Dyco  Oil  and  Gas  Program  1986-X  and  Dyco
                        Petroleum  Corporation  filed as  Exhibit  4.1 to Annual
                        Report on Form 10-K for the year ended December 31, 1991
                        on  April  1,  1992  and  is  hereby   incorporated   by
                        reference.

                  4.2   Program  Agreement  dated November 25, 1986 for Dyco Oil
                        and Gas  Program  1986-X by and between  Dyco  Petroleum
                        Corporation and the Participants filed as Exhibit 4.2 to
                        Annual  Report on Form 10-K for the year ended  December
                        31, 1991 on April 1, 1992 and is hereby  incorporated by
                        reference.

                  4.3   Amendment  to  Program  Agreement  for  Dyco Oil and Gas
                        Program  1986-X dated December 31, 1989 filed as Exhibit
                        4.3 to Annual  Report  on Form  10-K for the year  ended
                        December  31,  1991  on  April  1,  1992  and is  hereby
                        incorporated by reference.




                                      -40-
<PAGE>





                  4.4   Certificate of Limited Partnership, as amended, for Dyco
                        Oil and Gas Program 1986-X Limited  Partnership filed as
                        Exhibit  4.4 to Annual  Report on Form 10-K for the year
                        ended  December  31, 1991 on April 1, 1992 and is hereby
                        incorporated by reference.

                *27.1   Financial  Data Schedule  containing  summary  financial
                        information  extracted from the Dyco Oil and Gas Program
                        1986-X Limited Partnership's  financial statements as of
                        December  31, 1998 and for the year ended  December  31,
                        1998.

                  All other Exhibits are omitted as inapplicable.


                  ------------------
                  *  Filed herewith.


      (b) Reports on Form 8-K filed during the fourth quarter of 1998.

                  None.




                                      -41-
<PAGE>



                                   SIGNATURES

Pursuant to the requirements of Sections 13 or 15(d) of the Securities  Exchange
Act of 1934,  the  registrant  has duly  caused  this report to be signed on its
behalf by the undersigned, thereunto duly organized.

                                    DYCO OIL AND GAS PROGRAM 1986-X
                                    LIMITED PARTNERSHIP

                                    By:   DYCO PETROLEUM CORPORATION
                                          General Partner

                                          March 26, 1999


                                    By:   /s/Dennis R. Neill
                                          ------------------------------
                                          Dennis R. Neill
                                          President

Pursuant to the requirements of the Securities Exchange Act of 1934, this report
has been signed below by the following  persons on behalf of the  registrant and
in the capacities on the dates indicated.

By:  /s/Dennis R. Neill         President and               March 26, 1999
     -------------------        Director (Principal
        Dennis R. Neill         Executive Officer)

     /s/Patrick M. Hall         Chief Financial             March 26, 1999
     -------------------        Officer (Principal
        Patrick M. Hall         Financial and
                                Accounting Officer)

     /s/Judy K. Fox             Secretary                   March 26, 1999
     -------------------
        Judy K. Fox



                                      -42-
<PAGE>



                               INDEX TO EXHIBITS


Exhibit
Number      Description
-------     -----------

4.1         Drilling Agreement dated November 25, 1986 for Dyco Drilling Program
            1986-X,  a  Limited  Partnership,  by and  between  Dyco Oil and Gas
            Program 1986-X and Dyco Petroleum  Corporation  filed as Exhibit 4.1
            to Annual  Report on Form 10-K for the year ended  December 31, 1991
            on April 1, 1992 and is hereby incorporated by reference.

4.2         Program  Agreement  dated  November  25,  1986  for Dyco Oil and Gas
            Program  1986-X by and between Dyco  Petroleum  Corporation  and the
            Participants  filed as Exhibit 4.2 to Annual Report on Form 10-K for
            the year  ended  December  31,  1991 on April 1,  1992 and is hereby
            incorporated by reference.

4.3         Amendment to Program  Agreement for Dyco Oil and Gas Program  1986-X
            dated  December  31, 1989 filed as Exhibit  4.3 to Annual  Report on
            Form 10-K for the year ended  December 31, 1991 on April 1, 1992 and
            is hereby incorporated by reference.

4.4         Certificate of Limited Partnership, as amended, for Dyco Oil and Gas
            Program  1986-X Limited  Partnership  filed as Exhibit 4.4 to Annual
            Report on Form 10-K for the year ended December 31, 1991 on April 1,
            1992 and is hereby incorporated by reference.

*27.1       Financial Data Schedule  containing  summary  financial  information
            extracted   from  the  Dyco  Oil  and  Gas  Program  1986-X  Limited
            Partnership's  financial  statements as of December 31, 1998 and for
            the year ended December 31, 1998.


------------------
*  Filed herewith.
                                      -43-