Exhibit 23.5 PETROLEUM CONSULTANT'S CONSENT We consent to incorporation by reference in the Registration Statement on Form S-8 of Devon Energy Corporation, the reference to our appraisal report for Devon Energy Corporation as of December 31, 1998, which appears in the December 31, 1999 annual report on Form 10-K of Devon Energy Corporation. AMH GROUP LTD. ALLAN K. ASHTON Allan K. Ashton President October 3/00