Convolvulus, 91, 92 Coptis, 39 Corallorhiza, 16 Coral Root, 16 Coreopsis, 123, 124 Corispermum, 28 Cork Elm, 24 Cornaceae, 83 Corn Cockle, 33 Corn Flower, 121 Corn Gromwell, 94 Corn Salad, 111 Cornus, 83, 84 Corydalis, 42 Corylus, 22 Costmary, 121 Cotton Grass, 8 Cotton Thistle, 118 Cottonwood, 19 Cowbane, 81 Cowherb, 34 Cow Parsnip, 82 Cowslip, 36 Cow Wheat, 104 Crab, 54 Crab Grass, 5 Crack Willow, 20 Cranberry, 85 Cranberry Tree, 111 Crane-fly Orchis, 16 Crane's-bill, 64, 65 Crassulaceae, 48 Creeping Cedar, 1 Creeping Wahoo, 69 Crepis, 117 Cress, 43-47 Cress, Bitter, 45, 47 Cress, Field, 46 Cress, Garden, 45, 46 Cress, Lake, 45, 46 Cress, Mouse-ear, 47 Cress, Penny, 46 Cress, Rock, 46, 47 Cress, Water, 45 Cress, Winter, 44 Cress, Yellow, 43 Crotalaria, 59 Crowberry, 68 Crowberry Family, 68 Crowfoot, 35 Crowfoot, Cursed, 37 Crowfoot Family, 35 Crowfoot, Sea-side, 36 Crowfoot, Small-flowered, 36 Crowfoot, Water, 35, 37 Cruciferae, 42 Cryptotaenia, 82 Cuckoo Flower, 45 Cucurbitaceae, 112 Cudweed, 120, 121 Culver's Root, 104 Cup Plant, 123 Currant, 49, 50 Currant, Indian, 110 Cursed Crowfoot, 37 Cuscuta, 92 Custard Apple Family, 40 Cut-grass, 5 Cycloloma, 29 Cynanchum, 90 Cynoglossum, 93, 94 Cynthia, 115 Cyperaceae, 7 Cyperus, 8 Cypress Spurge, 67 Cypripedium, 18 Dactylis, 6 Daisy, Ox-eye, 131 Dalibarda, 56 Dame's Rocket, 47 Dandelion, 115 Dandelion, Dwarf, 115 Datura, 100 Daucus, 82 Day-flower, 9 Day Lily, 11 Dead Nettle, 99 Decodon, 77 Deerberry, 86 Dentaria, 44 Deptford Pink, 34 Desmodium, 62, 63 Devil's Club, 80 Dewberry, 53 Dianthera, 107 Dianthus, 34 Dicentra, 41 Diervilla, 110 Digitaria, 5 Dioscorea, 14 Dioscoreaceae, 14 Diplotaxis, 42, 43 Dipsacaceae, 112 Dipsacus, 112 Dirca, 77 Ditch Stonecrop, 49 Dock, 26 Dock, Prairie, 122 Dodder, 92 Dodecatheon, 87 Dogbane, 90 Dogbane Family, 90 Dog Fennel, 130 Dog Rose, 52 Dog's-tooth Violet, 12 Dog Violet, 76 Dogwood, 83, 84 Dogwood Family, 83 Downy Mint, 78 Draba, 42, 46 Dracocephalum, 96 Dragon Head, 96 Dragon Head, False, 99 Dragon Root, 8 Drop-seed, 5 Drosera, 48 Droseraceae, 48 Duckweed, 9 Duckweed Family, 9 Dulichium, 7 Dutchman's Breeches, 41 Dwarf Birch, 22 Dwarf Dandelion, 115 Dwarf Dogwood, 83 Dwarf Ginseng, 80 Dwarf Iris, 15 Dwarf Mistletoe, 25 Dwarf Raspberry, 53 Dwarf Water Plantain, 3 Dwarf White Trillium, 12 Dyer's Greenweed, 58 Echinochloa, 5 Echinocystis, 112 Echinodorus, 3 Echinops, 117 Echium, 94 Eel Grass, 3 Elaeagnaceae, 77 Elatinaceae, 74 Elatine, 74 Elder, 109 Elder, Box, 70 Elder, Marsh, 114 Elecampane, 127 Eleocharis, 7 Eleusine, 6 Elm, 24 Elodea, 3 Elymus, 6 Empetraceae, 68 Empetrum, 68 Enchanter's Nightshade, 78 English Plantain, 107 Epifagus, 106 Epigaea, 85 Epilobium, 79 Epipactis, 17 Eragrostis, 7 Erechtites, 122 Ericaceae, 84 Erigenia, 81 Erigeron, 130-132 Eriocaulaceae, 9 Eriocaulon, 9