I know the grasses can be a challenge to ID, but thought I'd give it a whirl. I photographed four variegated species over the weekend which were all approximately 12" or less in height and this is the second of them. All were on display at local public gardens so I presume they may be cultivars available in local nurseries in upstate NY area.

This particular grass was situated in full shade as an understory planting under pines in a very dry area and did not appear to be receiving any supplemental water.