A Matter of Circumstance - S11-E28
Continuity mistake: It is obvious that a wind machine was used in the opening scene. Dust, straw and leaves are blowing across the Ponderosa and trees in the foreground are swaying but the trees in the background are motionless. Two minutes later, a shot of a cloud-filled sky and a flash of lightning is shown and rain starts falling. In the next shot, Joe is inside the barn and sunlight is streaming through the windows even though rain is falling. Joe's horse then gets spooked by a lightning bolt and knocks Joe to the ground. The horse tramples him several times but when Joe is finally able to get up, the back of his shirt and pants are completely clean.