Q.Is this vole damage to my young arborvitaes?
I’ve noticed significant shallow tunneling along all of my newly planted 2 beds of about 4’ tall arborvitaes. There are no tunnels in my yard or other beds. I amended the nasty soil in which I planted the trees, with soil conditioner and 2 hand fulls of compost before placing the trees into their new holes. I’ve planted many of these trees before, however they’ve always been 8’ arborvitaes not this young. Not sure what to do!? I want to stay away from anything that will poison anything. The beds are along a very busy dog walking street, with many other animals around that I don’t want to inadvertently poison….

The shallow tunneling is characteristic of vole activity. The browning foliage may be a result of vole feeding on roots or stem, but this is not conclusive as there could be other reasons.
The following guide from DoMyOwn.com has four sections, review them all to get some good overview of identification and possibilities for control. Don't overlook the 'prevent' section that discusses repellents with some examples of products.
Since poison baiting is out, you may consider trapping.
https://www.domyown.com/vole-identification-guide-a-617.html