One of our favorite plants blooming this fall is goldenrod AKA Solidago. There is a goldenrod species for every situation: Dry. Moist. Sun. Shade. Tall. Short. You name it there is a goldenrod for your yard. However many folks fear goldenrod as they think they are allergic to it.
The likely culprit for the sneezes and watery eyes is ragweed. Blooming at the same time and with yellow flowers it is easy to mistake one for the other.
With a genus name like Ambrosia you would think Ragweed would be more attractive. It is attractive to bees, but not humans. Dispersing over 1 million grains of pollen into the wind ragweed is a constant source of misery for allergy sufferers. There are 4 species of ragweed native to Virginia with a wide range and a long bloom time(A. artemesifolia, A. bidentata, A. psilostachia & A. trifida), so likely ragweed is to blame for seasonal allergies.
With too many goldenrod species to list, it is a very common plant and blooming all over the commonwealth during Sept/Oct/Nov. Goldenrod however has very heavy pollen grains which are too big to be airborne and fall to the ground when dispersed. This means that allergies to goldenrod are likely non-existent.
SO, How to tell them apart?
LEAVES
Ragweed leaves are generally deeply cut while goldenrod leaves are slender and toothed. Ragweed left, goldenrod right.
FLOWERS
Goldenrod flowers range from lemony to golden yellow and are very showy while ragweed flowers are barely yellow and not showy at all. Ragweed on Left Goldenrod on right.
Knowing which is which can help us all appreciate goldenrod which often gets a bad wrap. It is also the host for numerous pollinators and habitat for many of our native bees.