OR Rev Stat § 201.230 (2021)
2021 Oregon Revised Statutes|Volume : 06 - Local Government, Public Employees, Elections|Chapter 201 - Boundaries of Counties|Section 201.230 - Malheur County.

The boundary of Malheur County is as follows: Beginning at the intersection of the south boundary of the state and the range line between ranges 38 and 39, E. W. M.; thence north along the range line to a point where the range line intersects the south boundary of township 37 south; thence west along the township line to the range line between ranges 36 and 37 east; thence north along the range line to the northwest corner of section 19, township 15 south, range 37 east; thence east along the section line to the southwest corner of section 16; thence north along the section line to the northwest corner of the section; thence east along the section line to the southwest corner of section 11; thence north along the section line to the northwest corner of section 2; thence east along the township line to the southwest corner of section 36, township 14 south, range 37 east; thence north along the section line to the northwest corner of the section; thence east along the section line to the southwest corner of section 30, township 14 south, range 38 east; thence north along the range line to the northwest corner of section 30; thence east along the section line to the southwest corner of section 20; thence north to the northwest corner of the section; thence east along the section line to the southwest corner of the southeast quarter of the southwest quarter of section 17; thence north to the northwest corner of the northeast quarter of the northwest quarter of the section; thence east along the section line to the southwest corner of section 9; thence north along the section line to the northwest corner of the section; thence east along the section line to the southwest corner of section 3; thence north along the section line to the northwest corner of the southwest quarter of the southwest quarter of section 34, township 13 south, range 38 east; thence east to the northwest corner of the southwest quarter of the southwest quarter of section 35; thence north along the section line to the northwest corner of section 26; thence east along the section line to the southwest corner of section 24; thence north along the section line to the northwest corner of the section; thence east along the section line to the southwest corner of section 17, township 13 south, range 39 east; thence north along the section line to the northwest corner of the section; thence east along the section line to the northeast corner of section 17, township 13 south, range 42 east; thence south along the section line to the southeast corner of the section; thence east along the section line to the northeast corner of section 21; thence south along the section line to the southeast corner of the section; thence east along the section line to the northeast corner of section 26; thence south along the section line to the southeast corner of the section; thence east along the section line to the northeast corner of section 36; thence south along the range line to the southeast corner of the section; thence east along the township line to the northeast corner of section 6, township 14 south, range 43 east; thence south along the section line to the intersection of the south boundary line of township 14 south, range 43 east; thence east on the south boundary line of township 14 south, to the middle channel of the Snake River between Oregon and Idaho; thence up the meanderings of Snake River on the line between Oregon and Idaho to the mouth of the Owyhee River on such line; thence south on the line between Oregon and Idaho to the north line of Nevada; thence west on the north line of Nevada to the place of beginning.