Great pics and healthy plant. It would be interesting to see it survive. Christmas lights for cold nights and cover with a large container weighed down. Is it in a sunny spot? My parents have a huge one in FL and its not unusual for bugs to like them. Ants don't hurt plants generally b/c they are using it as a source for one thing or another.

The presence of large numbers of ants is often associated with other problem insects--aphids and/or mealybugs. The ants actually use these insects for harvesting sweet secretions of honeydew (I believe it's called). Ants may also be a sign of some truck decay.--I had a large cycad specimen that had a rotted out cavity in the trunk and a colony of ants seems to move in--that plant eventually died. Definitely protect from winter snow, ice and rain.

brooklyngreg...it gets a lot of sun in that location. Not so much morning sun but lots of midday and late afternoon sun. The ants always seem to be all over the roots. I wasn't sure if they were eating the roots or not!

njoasis...could it be they're eating dead parts of the root?

I don't believe that ants do the damage directly. If there is a strong ant problem though, it may be an indication of a pre-existing problem (decay, other insect infestations, etc.)