I've owned 8 cats in my life, plus countless fosterlings, and not one of them has had the faintest interest in Christmas trees. Until our youngest, 1.5 yrs, who despite ignoring it last year when he was a kitten now cannot be kept out of it. Our living room is a carpet of chewed pine needles, and the soundtrack is of jingling ornaments and scrabbling claws.
Doesn't help that he's a chunky boy, and I fear even my compression-strapping the base to four breeze blocks may not get us safely through the season.