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    Filed Pursuant to Rule 425
Filing Person: Evergreen Resources, Inc. (001-13171)
Subject Company: Carbon Energy Corporation (1-15639)

        Four slides included in a presentation by Mark Sexton, President and Chief Executive Officer of Evergreen Resources, Inc., to Hibernia Southcoast Capital on March 31, 2003 related to Evergreen's proposed acquisition of Carbon Energy Corporation. These slides may also be included in subsequent presentations by Mr. Sexton or other officers of Evergreen.

        The first slide graphically depicts the location of Carbon Energy's U. S. assets in the Uintah Basin of Colorado and Utah and the Piceance Basin in Colorado.

        The second slide graphically depicts the location of Carbon Energy's Canadian assets in three locations in the Western Canadian Sedimentary Basin (Rowley, Carbon and Hoffer).

        The third and fourth slides are set forth below:


Carbon Energy U.S. Assets                                EVERGREEN

         LOGO


Carbon Energy — Canada Assets                                EVERGREEN

         LOGO


Carbon Energy Acquisition                                EVERGREEN


Carbon Energy Acquisition                                EVERGREEN

Carbon Summary

 
  United States
  Canada
  Total
Gross acreage position   150,000   77,000   227,000

Current Daily Production (mmcfd)

 

5.0

 

8.3

 

13.3

Reserves (mmcfe)

 

 

 

 

 

 
 
Total Proved Developed

 

21,790

 

20,506

 

42,296
  Proved Undeveloped   34,805   10,618   45,423
   
 
 
 
Total Proved

 

56,595

 

31,124

 

87,719
   
 
 
 
Probable

 

20,493

 

7,964

 

28,457
  Possible   103,380   10,618   113,998
   
 
 
 
Total Probable & Possible

 

123,873

 

18,582

 

142,455
   
 
 
 
Total Proved, Probable and
Possible reserves

 

180.468

 

49.706

 

230.174
   
 
 



QuickLinks

Carbon Energy U.S. Assets EVERGREEN
Carbon Energy — Canada Assets EVERGREEN
Carbon Energy Acquisition EVERGREEN
Carbon Energy Acquisition EVERGREEN