If you gently brush away the foam, you will find a small pale colored grub inside. As kids we called them spittle bugs, but I don't know their scientific name. They create the foam for protection using the plant fluids.

Thanks nhbabs. Definitely spittlebugs after googling.

I keep reading to blast them out with the jet setting on your hose and then squish them. Since my plants are still to delicate to "blast" I may have to pry them out and then squish them.

Any other recommendations?

A minor annoyance not a serious damage to plants. Takes very little spray to remove them. Al

Should you begin finding more and more of the spittle bug 'nests' you might want to get after them with insecticidal soap. It's the nymphs that are in the foam, the adults are one of several species of leafhopper or planthoppers. Adults and nymphs alike suck plant juices from their host plant, and adults are infamous for spreading pathogens from plant to plant.

If you've been noticing only a few...don't worry. If the population seems troublesome, use a good commercial brand of insecticidal soap sprayed directly on the foam and onto the critter.

Asters and spittlebugs go hand in hand.

Here is a link that might be useful: Species of adult spittlebugs

We call it cuckoo spit here and the little green bug we call a froghopper. It has froggy bug eyes. A squirt from the hose will dislodge them.

Thanks again for everyone's input. Very happy to hear overall I shouldn't be too concerned since mine definitely is not wide spread. I will take everyones notes when I start moving some of them this weekend to new locations (crazy how 3 small plants bought from Bluestone turned to roughly 25+ this year...wayyyy over crowding the space...guess they like the location).