Plant ID help

I took Oji's advice to Manumuskin, about photographing three plants and identifying each, to become acquainted with the species growing in the Pinelands. Two of the the random photos today, were difficult, but not impossible to identify with the help of Hough's book New Jersey Wild Plants and Google images. The third has me stumped. I believe it to be Desmodium. Thanks for any help.

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