Goldenrod is a native perennial that’s gaining popularity ... The true culprit that causes allergies in the autumn is ragweed (Ambrosia artemisiifolia), which blooms around the same time as ...

Western ragweed (Ambrosia psilostachya), on the other hand, is a perennial, so it could take years of mowing before it is eradicated. Because of this, herbicides are often a necessary evil when it ...