The unnamed squirrel in this short makes a cameo appearance at the end of Looney Tunes: Back in Action (2003).
Mid century Americans enjoyed nuts of all types. Many of those varieties are shown here, though hazelnuts (filberts), cashews and pecans were also popular. Specialty stores sold all types of nut based products. Today, retailer nuts dot com continues the tradition online
Brazil nuts do indeed come from South America, hence their name. The trees can grow quite large. The nut produced is considered a gourmet delicacy in many places and has also been made into a spreadable butter, too.
The setting for this nutty tale is, of course, central Manhattan, with cameos of Central Park and the Empire State Building making appearances.
The squirrel in this short might have helped inspire the character Scrat, the saber toothed squirrel from the Ice Age film franchise.