From the amusing Bonanza episode "Hoss and the Leprechauns" from 1963, which strangely enough did not air near St. Patrick's Day but on December 22! This is a little scene featuring Little Joe (the charming Michael Landon) teasing his older brother (the wonderful Dan Blocker) after Hoss thinks he spied some leprechauns burying a box of gold.
The whole episode is available on YouTube in several parts, beginning here. You can always tell it will be a fun Bonanza when it starts out with composer David Rose's theme music for Hoss, a sure sign you're in for some Ponderosa hijinks! (For more info on this great series, check out the Bonanza: Scenery of the Ponderosa website!)