Although he earlier had trained horses belonging to his father, Omer Jennings, who once owned the Pimlico Hotel, the younger Mr. Jennings began training other horses in 1954 at Maryland tracks. He kept horses at Maryland tracks until 1960, adding Monmouth Park in New Jersey as a racing venue in 1957.
He is survived by his wife, the former Glenna D. Kiser; six daughters, Katherine Aukerman of Lewisburg, Pa., Patricia Lee of Baltimore, Karen Gray of Millersville, Susan Hancock of Pasadena, Lorraine Martin of Severn and Carol Czumbil of Morrisville, Pa.; a brother, William R. Gray of Natrona Heights, Pa.; three sisters, Jeanne Wylie of Yukon, Okla., Kass Ellis of the Pittsburgh, Pa., area and Elizabeth Lukshin of Austin, Texas; and 12 grandchildren.
The Baltimore native was a graduate of Mount St. Joseph High School and the University of Maryland Baltimore County. He also had a master's degree from Frostburg State University. He served in the Army in the mid-1960s.