Continuity mistake: A mooring rope breaks and sends a hot-air balloon rising into the air. No one is in the gondola. Stock footage shows a hot-air balloon in the sky but a man is visible in the gondola.
Continuity mistake: Red Twilight, believing his brother's death was caused by Hoss Cartwright, gets revenge by shooting Hoss in the back. When he learns Hoss is still alive, he goes to the Ponderosa to finish the job. Red shoots and kills a ranch hand, then enters the home. Little Joe gets into a fight with Red and both men run out into the yard. The ranch hand's body has disappeared.
Audio problem: Apparently there was a problem with the sound recording during a scene of Ben Cartwright speaking to his son Adam while standing by the chuck wagon. One of Ben's lines was dubbed in by someone else whose voice was higher-pitched and less gruff than that of actor Lorne Greene.
Other mistake: An Army friend of Ben's uses Ponderosa land to test his hot-air balloon. There are very few clouds in the sky. A balloon in flight is shown but it is obviously stock footage. The sky is filled with clouds and the film contains several black spots and scratches.
The Secret - S2-E31
Continuity mistake: At the Ponderosa, Jake Parson is telling Ben Cartwright of his suspicion that his daughter eloped with Little Joe. The grandfather clock shows the time as 8:53. Both men turn as they hear the door open. As Little Joe walks in, the time has suddenly jumped to 8:59.
Character mistake: "Bonanza" is set in the 1860s but this episode uses three phrases which, according to the Merriam-Webster Dictionary, did not enter our vocabulary until much later: "Trouble-shooter" dates from 1905, "mother hen" dates from 1934 and "sitting duck" dates from 1942.
The Rescue - S2-E23
Revealing mistake: The mountains outside the dining room window of the Ponderosa house are obviously part of a painted backdrop. As Ben walks past the window and sits at the table, he casts a shadow on the mountains.
Revealing mistake: When Gunnar lifts Vaca over his head during the fight, in the closeup he's holding up a barrel over his head instead of Vaca and throws the barrel. (00:35:05)
Factual error: "Bonanza" is set in the 1880s. In this episode, Little Joe and a friend discover a site where a man and his wife and daughters were attacked by Apaches. A Raggedy Ann doll is among the rubble. Johnny Gruelle did not create the Raggedy Ann character until 1915.
The Rescue - S2-E23
Continuity mistake: When Ben is shot at he falls on his right side. When the shooter goes to check it out he's on his left.
Continuity mistake: A flashback episode set in the 1840s opens with Ben Cartwright as a first mate aboard a clipper ship. Rear-screen projection shows an ocean and a grey overcast sky. In a shot of the crew on the rigging and in the crow's nest, the sky is deep blue with a few white clouds.
Factual error: In a flashback episode set in the 1840s, Ben Cartwright and his former Captain are operating a ship's chandler business. A competitor accuses them of running a "flea market." That term is a translation of the French "marché aux puces" and did not enter the English language until 1922.
Factual error: Joe Cartwright gives a Raggedy Ann doll to a young woman named Annie. "Bonanza" is set in the late 1860s. The Raggedy Ann character was created by Johnny Gruelle in 1915.
Other mistake: A windstorm in the opening scene was obviously created by a wind machine. The branches of the trees in front of the Ponderosa are swaying, but no dust or leaves are blowing on the ground, and the trees in the background are motionless.