Campanulaceae, the bellflower family.
Plant: A slender, smooth stem bears light violet, bell-shaped flowers 1"-1.5" wide along an upright stem with sparse, narrow, toothed leaves. 1'-2' high overall. Perennial.
Flowers: Light violet, bell-shaped, with five shallow lobes, 1"-1.5", on short stems arising from leaf axils. Stigma divided into three parts (sometimes 4).
Leaves: Very narrowly ovate to linear, toothed, stemless, to 4" long.
Fruit: A dry capsule about 1/2" long.
Habitat: Disturbed fields, roadsides, waste ground.
The pictured flower is some species of non-native bellflower; it is
similar to the widely naturalized creeping bellflower (C. rapunculoides)
but does not seem to match exactly.
Possibly some other escaped European import.
Where to find it:
I have found this flower in only one location, a depression on the east
boundary of the park near the professional buildings.