Aren't you wondering if it wasn't just the other day when we looked at cinquefoil? You are correct, my dear and astute reader. Only thing is that today it's the Rough-fruited Cinquefoil, Potentilla recta, making its debut. The leaves and flowers are similar but the stalk holds the uniqueness here--straight with subdued green coloring, not at all like the Common Cinquefoil's crimson vininess.
From a fine and familiar author:
"A similar stout plant with a characteristically rough horned seed vessel. The five rather narrow leaflets are deep green, very hairy beneath, and slightly so above. The flowers are pure yellow, and 3/4 inch broad; the petals are much larger than the lobes of the calyx(flower envelop ) which is the reverse of the case with the Norway cinquefoil. Erect 1-2 feet high. Adventive from Europe and in the vicinity of old gardens and waste grounds Me south to Va and west to Mich Found at Exeter Penobscot Co., Me."
Mathews, Ferdinand Schuyler. Field Book of American Wild Flowers. New York, 1902. 198. Web. Google Book Search. Web. 20 Jun 2009.