They're baaack!

What do you do about that ?

It's early days for that nest, Brian. If left to develop there would be hundreds of inch long caterpillers that would completely defoliate the tree. They lay eggs in the bark or in unmolested tents from the previous season. Last summer was a bad year. They are prevalent in seven year cycles which should mean that this will be a scarce year for them.
I have used fire to cook the nests but find the best, but most disagreeable method is crushing them with my hands or removing the branch/twig and using a spray bottle of sudsy water on the twigs and branches surrounding and beneath the nest. The caterpillars travel by silk so it's not unusual to experience a "drop in" when walking in the forest in bad infestations.

Let's hope you can keep them at bay Lori

Could you just brush them off the tree? A modified broom?

Or a bird feeder put there...and then you can remove it when the pillars are done for.

Sometimes, on rainy days they leave the nest and congregate on the trunk of the tree. Then it's easiest to squish them. Checked them out and got rid of two batches today. They're still flying on their silk and it's common to find them in the bathroom and on the rug, etc... creepy crawllies...