Coefficient of Conservatism:
Coefficient of Wetness:
A. A. Reznicek
A native of Europe and adjacent Asia, long cultivated and considered to have medicinal properties. In dry or swampy, often ± shaded disturbed ground: roadsides, railroads, dumps and refuse heaps, around buildings, farmyards, parking lots; dry open forests (e.g., oak), weedy floodplains, river banks, thickets, sandy banks and fields. Collected in Michigan as early as the First Survey (1837) in St. Joseph Co.
This is a tall, hard-stemmed plant, with the spiny calyx lobes spreading to reflexed at maturity. The nutlets are strongly 3-angled, flat and pubescent at the apex. The upper lip of the corolla is long-pilose, the buds thus appearing like hairy plugs in the calyx. A few specimens collected in the fall bear leaves (late-formed?) with rather rounded lobes and short sinuses, resembling those of a Ribes, rather than the usual shape with 3 long sharp-pointed lobes.