Leathery knotweed. If you Google this weedy little plant, that is just about all you can find about it. For a plant that has many useful relatives, it's unusual to find one that's flown this much under human radar. It pops up in disturbed sites and other areas with depleted soil, so it has some value in that early stage of reclamation. Leathery knotweed is an American native, now found in AK, CO, CT, IA, ID, IL, IN, KS, ME, MI, MN, MO, MT, ND, NE, MT, ND, NE, NY, OH, OR, PA, SD, VT, WI, WV, WY, AB, BC, MB, NB, NS, NT, ON, PE, QC, and SK. Lenawee Co MI, 8/4/11. Knotweed family, Polygonaceae.