My dad, Dale Tussing, wrote a double parody of O Tannenbaum and The Worker's Flag, which I think is up there with Pogo's Deck Us All With Boston Charlie.

Our Christmas tree is painted green
It's manufactured by machine.
Ere its limbs grow stiff and cold,
The green paint's dyed on every fold
So raise the sylvan banner high
Our Christmas tree will never die.
Though cowards flinch and traitors sneer,
We'll keep our Christmas tree all year.