11a. Leaves ovate, with a heart-shape base =Stinging Nettle, Urtica dioica.= 11b. Leaves lanceolate or ovate-lanceolate, not heart-shape at base =Slender Nettle, Urtica gracilis.= 12a. Stems glabrous, pellucid =Clearweed, Pilea pumila.= 12b. Stems rough, opaque =False Nettle, Boehmeria cylindrica.= SANTALACEAE, the Sandalwood Family Low herbs with alternate entire leaves and terminal clusters of small greenish-white bell-shape flowers without petals in spring and early summer. 1a. Inflorescence of several-flowered clusters terminating the stem and in the upper axils =Toad-flax, Comandra umbellata.= 1b. Inflorescence of axillary clusters of 1-5 flowers =Toad-flax, Comandra livida.= LORANTHACEAE, the Mistletoe Family Parasitic plants, attached to the branches of trees. One species in Michigan, a dwarf brown plant 5-20 mm. long, with minute scale-like leaves, growing on the branches of Black Spruce =Dwarf Mistletoe, Arceuthobium pusillum.= ARISTOLOCHIACEAE, the Birthwort Family Flowers greenish-brown or reddish-brown, at or near the ground, with inferior 6-celled ovary. 1a. Leaves alternate, on the stem; flowers on a basal scaly branch (1-4 dm. high; summer) =Virginia Snakeroot, Aristolochia serpentaria.= 1b. Leaves a single basal pair, bearing 1 short-stalked flower between them (spring) (Wild Ginger) --2. 2a. Lobes of the perianth ending in a tubular portion 5-8 mm. long =Wild Ginger, Asarum canadense.= 2b. Lobes of the perianth ending in a tubular portion over 1 cm. long =Wild Ginger, Asarum canadense var. acuminatum.= 2c. Lobes of the perianth triangular, not tubular at the end =Wild Ginger, Asarum canadense var. reflexum.= POLYGONACEAE, the Buckwheat Family Herbs with alternate entire leaves, stipules surrounding the stem above the base of each leaf, and small green, white or pink flowers without petals. 1a. Erect or ascending or prostrate or floating plants --2. 1b. Scrambling or climbing plants, clinging by sharp recurved prickles on the 4-angled stems (flowers greenish or pink, summer) (Tear-thumb) --32. 1c. Twining vines (flowers white or greenish, summer) --33. 2a. Sepals 6, the 3 inner ones enlarging in fruit and surrounding the achenes; flowers in panicles --3. 2b. Sepals 4 or 5 (occasional flowers may be found with 6 sepals, but the flowers are not in panicles) (summer) --13. 3a. Leaves arrow-shape or halberd-shape, with 2 basal lobes (Sorrel) --4. 3b. Leaves without basal lobes (Dock) --5.