I don't know the answer..my lot is wooded with minimal grass which has never been treated..but even though the hostas weren't growing that area didn't look like turf right?..so I don't think they should've sprayed it..you're nicer than me..if there's problems I would call them..would it help to water that area and dilute the herbicide?

Our back yard is so shaded there's not much turf at all. I know it was difficult to tell where the hostas are. However, some are marked....

and there was spray on those areas as well. :\

From what I know of preemergents, your Hosta will be fine. Preemergents can only burn little tiny root (hairs). Existing plants don't feel it, but freshly germinated seed have their little tiny root burned off and die.

I would rake all the leaves off as soon as possible. Steve is right, pre-emergents will burn off the tiny root hairs, and mature hostas have lots of those tiny root hairs. You don't see them because most hostas are sold and shipped bare root, having first been spray washed. That removes the tiny root hairs.

I believe this is responsible for the common belief that newly planted hostas sleep the first year, then they creep the second year, then they leap the third year. The reality is that hostas with nice clean white root systems are going to take 2 years to grow new tiny roots, which are necessary to the plant sending out new growth. Hostas that are dug and replanted with as much dirt as possible left on the roots put on normal growth the first year.

Gee, your lawn company sounds a lot like the "landscape workers" employed by my former co-op apartment management. A bunch of ignorant yahoos who probably couldn't read English given deadly poisons to spray about indiscriminately. I wish you the best of luck saving your hostas. They sprayed weed killer right up to the border fence separating my fully emerged hostas, killing a lot of leaves and leaving many other of my hostas disfigured for the rest of the season.