This is either Daisy fleabane (Erigeron strigosus) or Annual Fleabane (Erigeron Annuus), and it is not a weed. I keep wanting to think that it is, but it is not. It is actually a member of the daisy family. "Erigeron" comes from the Greek for "early old man," having to do with its bloom-time and the appearance of many tiny white hairs on the stem. There are 173 species of fleabane in N. America. Plants with the word "bane" included, as said to be the spoiler of the associated object or condition - the
"bane of fleas."
People looking for alternatives to buckthorn have wonderful native shrubs to consider. One of my favorites is Ninebark (Physocarpus opulifolius). Called ninebark because the bark on mature branches peels off to expose layers of reddish brown inner bark. This specimen is in the marsh area of the bog in the Garden and is quite tall, in excess of 6 feet, but may be pruned if a shorter profile is desired.
At the Garden, the prairie is blushing with Foxglove penstemon (Penstemon digitalis). This is not the digitalis employed as a heart medicine, but a look-alike. Penstemon are so popular that there is an Americian Penstemon Society.
I love this flower (Geum triflorum) - it is called a lot of things - my favorite name for it is Prairie smoke,
but I actually think it looks a lot like Beaker, the Muppet. It is also called Pasque flower (an anemone), although that name seems to properly belong to Pulsatilla vulgaris but it is only fair, as that plant is sometimes called Prairie smoke. The two plants are very distinguishable, with the smokey aspect of the geum being in its inflorescence and in the other, an anemone, in its leaves. Around here, the anemone blooms around Easter time, hence the name Pasque flower. I can imagine either plant blanketing a prairie ridge, giving the appearance of a smoldering fire. In the setting sun, this little bloom appeared to be spangled with mica, but my camera could not capture it.