Wildflowers, particularly members of the aster family, are still decorating the roadsides in our area in September.
Asters (genus Symphyotrichum and Eurybia)
Asters are very prevalent along the roadsides here in mid-September. Minnesota has many species of Aster, within the genus Symphyotrichum the Minnesota Wildflower website lists 19! The first two asters shown in the slideshow below have white petals. I believe the first of these shows the Panicle Aster and the second is the Calico Aster. The following four slides are blue/violet asters and there are many species these could be: Lindley’s Aster, Smooth Blue Aster, Large-Leaved Aster, Sky Blue Aster… maybe others too.
Tall Goldenrod (Solidago altissima)
Goldenrod is another very common roadside wildflower here in September. It is actually in the same family as asters (Asteraceae). Like the asters, there are numerous species of Goldenrod, I believe Tall Goldenrod is the one most often seen locally.
Goldenrod is widely believed to cause seasonal allergies, but this is not true. Goldenrod pollen is too heavy to be wind-borne. Ragweed produces wind-blown pollen at the same time that Goldenrod blooms; it is likely responsible for the bad reputation of Goldenrod.
While Goldenrod is generally considered a weed in North America, it is regarded as a desirable garden plant in Europe.
Common Ragweed (Ambrosia artemisiifolia)
Ragweed was mentioned as the true culprit largely responsible for seasonal allergies (not Goldenrod). So, it seems appropriate to show what it looks like.
This picture of Ragweed was taken in July, before it produced its characteristically non-showy flowers. It is very common alongside our gravel roads, but I confess that I did not realize its identity until using the Picture This app…