Ethel Evelyn Oatman Peters, 71, Who taught horticulture, landscape gardening and flower arranging, died of cancer Sunday at Georgetown University Hospital.

She was a master flower show judge, a nationally accredited landscape critic and instructor of horticulture in flow show schools.

Mrs. Peters, who had taught in eight states, had received citations from the National Council of State Garden Clubs for her work in design education.

She was a member of the board of trustees of the National Capital Arca Federation of Garden Clubs and had been active in annual flower and garden shows.

Born in Lawrence, Kan., Mrs. Peters received a degree in home economics from Kansas State University. She taught home economics in Mississippi and Florida.

She came to this area in 1941, and during World War II was active in the Girl Scouts, serving as president of the Girl Scout Leaders Association.Mrs. Peters left this area in 1945, but returned four years later and had lived here since then.

She had been a member of the Council of Accredited Flower Show Judges, the Landscape Critics Council, the Washington Daffodil Society and the Wesley Heights-Spring Valley Garden Club, and had been a guide at the National Arboretum.

Mrs. Peters had belonged to the Christian Women's Fellowship of the National City Christian Church, the PEO, a philantropic group, and the Twentieth Century Club.

She is survived by her husband, Kenneth, of the home in Gaithersburg; a daughter, Kennetta Russ, of Springfield, Mo.; a son, Merz Kenton, of New York City, and six grandchildren.