In my garden. I believe it is a herb. Comes back every year. Does any one know? Its about 1.5-2 feet tall.
It looks like some kind of Artemesia but a picture of the whole plant would help.
Doesn't look like tarragon to me. I've been growing tarragon for years. I'm thinking some kind of Artemisia, too. Does it have a fragrance/odor?
It looks very similar to Artemesia "Silver King", a variety of A. ludoviciana.
It is often dried and used in wreaths and dry flower arrangements.
Also very similar to Mugwort Artemisia vulgaris (a common weed).