Juniperus horizontalis 'Youngstown' Bob Fincham, Coenosium Gardens, explained about this cultivar "Juniperus horizontalis 'Youngstown' (1973) is a selection of 'Plumosa Compacta'; but lower growing, very flat, bright green: originated by Plumfield Nurseries, Fremont, Nebraska".
Iseli list this plant as Zone 2 and I would not disagree. I live in zone 3a and even during a very bad winter some 3 years back I did not observe any damage to this plant.
I will add that this cultivar exhibits an outstanding plum-purple color beginning after the first fall frost. The color deepens as the winter progresses returning to a dark green in the spring.
I have purchased some plants that were labeled 'Youngstown' but are clearly either reversions to Juniperus horizontalis 'Andora Compacta' or they were mislabeled. I believe that such mislabeling is common with this cultivar. One big distinguisher is the fall plum color. My 'Youngstown' appear a more pleasant intense color than the 'Andora Compacta' which is a plum-gray color.
