Thank you for the ideas! Scat spray might do the trick...
Not worried about the dogs at all...other than accounting for their tail wagging, their behaviour around Christmas trees is 100%. But Rupert...well...he'll be good for a month or so and then he's swinging from the rafters again, so to speak.
Chase (Friendly Resident Wigglebum) - Border Collie/Lab/Shepherd X
Kailey (Misunderstood Gentle Beauty) - GSD & foster failure #1
Rupert (Gold-Medal Winner of the 3 a.m. Kitty Destruction Olympics
Heidi - RIP my sweet baby girl