So often I hear folks blaming goldenrod as the source of their allergy suffering, when they really mean to say ragweed. The three species of goldenrod that we most often see in our coastal north of Boston fields, meadows, woodland edges, and dunes are Seaside Goldenrod (Solidago sempervirens), Tall Goldenrod (Solidago altissima), and Canada Goldenrod (Solidago canadensis). All three have beautiful yellow flowers, Seaside blooming a bit after Canada and Tall, and all are fabulous pollinator plants, providing nectar for bees, butterflies, and migrating Monarchs.
In our region, we most often encounter Common Ragweed (Ambrosia artemisifolia), with Plain Jane tiny green flowers and raggedy looking foliage. Goldenrods and ragweeds both bloom at roughly the same time of year, in mid- to late-summer, but why is ragweed the culprit and goldenrods are not? The colorful showy flowers of goldenrods are attractive to pollinators and they are both insect and wind pollinated. The drops of goldenrod pollen are too large to fall far from the plant. Ragweed’s tiny flowers are not of interest to most pollinators and the plant has evolved to rely on the wind to disperse its pollen from plant to plant. Ragweed produces massive amounts of teeny, breathable pollen to travel widely on the wind.
Although many of us are fortunate not to be bothered by ragweed, I completely empathize with friends who are. If it is any consolation, I recently learned two good uses for Common Ragweed. Shetland sheep love to eat it and it is good for their wool. And I have been following a flock of Cedar Waxwings for over a month. I often see in the morning the Waxwings descend on patches of mixed weeds, mostly Common Ragweed. Waxwings change their diet in summer to include insects and I think the birds are attracted to the plant for the host of insects it supports. So next time you are ragging on ragweed remember, it is a native plant and it does support a community of insects and birds.