Thanks for the response. I guess it's possibly the town you mentioned, but I'll have to do more research. I know I have very little to go on at this point. I think though that the Grudlitz/Gradlitz the Chyruska family was from may have been in an area with a large German population. I'm only guessing, but since they moved to German territory, and the wife's maiden name was listed as Frieblin (possibly Friebolin?) I think they may have had German ancestry.
Is it also possible that Hruska is an Americanized version of the surname, but again at this point I have very little information and know vertually nothing about Czech surnames/history. All I know is that apprently the name was spelled Chyruska when the family lived in Bohmen, but changed it to Shiruska when they settled in German. So Hruska certainly sounds like another possible variant. I'll have to find out more.