Early aster

The first of the wild asters have started to bloom. There are many different species around here, the premier blooms of which always have white flowers with yellow centers. In the yard, they're something of an invasive pest, but along my walking route, their unassuming and pretty blooms are a small joy. They're also a species of small sadness, since their arrival signals the beginning of the end of summer, which, give the chill this morning—it was nudging the upper 40s—never really got started. That said, my guess is that we still have at least a month of warmth ahead, so what the aster season augurs is simply the advent of the transition. So, begone melancholy, and in its place, insert taxonomy. I need to figure out the identities of the various asters, and if I kick in the goldenrods, which are equally numerous and tricky to ID, that should keep me from untoward thoughts. As to this one, Peterson proclaims that "many [species] can be recognized with certainty only by technical characters not given [in the field guide]." Time to start collecting.