If it was ornamental, as you say, with narrow leaves, and I'll add finely dissected leaves I agree with Worth that it probably was Silvery Fir Tree , which some grow for the foliage and not the fruits, as well as the reverse,
It's referred to as having carrot top foliage and is also know in some circles as Carrot Top although Andrey and I think Tania suggest that the two aren't exactly the same:
http://t.tatianastomatobase.com:88/w...lvery_Fir_Tree
Lots of seed sources for it, as noted in the link above, so more pictures at those sites as well as Google IMAGES if you want to see more.