[4] Jenson was a lumberjack and a construction worker before he joined the United States Navy in World War II.

He also appeared in 1967 as “Dace Edwards” (a ranch hand) in S3E6's “Ladykiller” on the TV Western Series The Big Valley.

A prolific character actor, Jenson appeared in such films as The Missouri Traveler, Warlock, 13 Ghosts, How the West Was Won, Waterhole No.

3, Our Man Flint, Big Jake, Harper, Bustin' Loose, Soylent Green, The Getaway, The Way We Were, The Outfit and Chinatown.

He also worked frequently with directors John Milius (Dillinger, The Wind and the Lion, Red Dawn) and Clint Eastwood (Thunderbolt and Lightfoot, The Gauntlet, Every Which Way but Loose, Any Which Way You Can, Honkytonk Man), as well as actor Geoffrey Lewis.