Hormidium, 58
Horned Pondweed, 19
Horned Pondweed Family, 19
Horned-rush, 43
Horsetail Family, 11
Horsetails, 11
Huguenot Fern, 15
Hurricane-grass, 42
Hydrilla, 21
Hydrocharitaceae, 21
Hydrochloa, 28
Hymenachne, 28
Hymenocallis, 54
Hymenophyllaceae, 12
Hyparrhenia, 28
Hypolepis, 14
Hypoxis, 54

Ibidium, 61, 62
Illinois Pondweed, 19
Imperata, 28
Indian Cucumber-root, 52
Indian Grass, 35
Indian Lovegrass, 26
Indian Shot, 57
Ionopsis, 60
Iridaceae, 55
Iris, 56
Iris Family, 55
Isoetaceae, 10
Isoetes, 10
Isotria, 60
Italian Ryegrass, 29

Jack-in-the-pulpit, 46
Japanese Brome, 23
Japanese Climbing Fern, 12
Japanese Lawngrass, 37
Johnson Grass, 35
Joint Grasses, 29
Juncaceae, 50
Juncaginaceae, 20
Juncoides, 51
Juncus, 50
Junegrass, 28
Jungle-rice, 26
Juniperus, 18

Kangaroo Grass, 36
Kentucky Bluegrass, 33
Key Grass, 29
Knotgrass, 32


Knotroot Foxtail, 35
Koeleria, 28
Kyllinga, 39, 40

Lachnanthes, 53
Lachnocaulon, 48
Ladder Brake, 15
Ladies' Tresses, 61
Lady Fern, 13
Languas, 57
Large Crabgrass, 25
Lasiacis, 28
Leafless Vanilla, 62
Leafy Vanilla, 62
Leather Ferns, 12
Leersia, 28
Leiandra, 49
Lemna, 46
Lemnaceae, 46
Lepanthopsis, 60
Leptochloa, 28
Leptoloma, 29
Liliaceae, 51
Lilies, 51
Lilium, 51
Lily Family, 51
Limnobium, 21
Limnodea, 29
Limodorum, 58
Liparis, 60
Lip Ferns, 13
Lipocarpha, 42
Listera, 60
Litobrochia, 15
Little Barley, 28
Little Bluestem, 34
Little Quaking Grass, 23
Loblolly Pine, 18
Lolium, 29
Lomariopsis, 14
Longleaf Pine, 18
Lophiola, 53
Lorinseria, 14
Lovegrasses, 26
Luziola, 29
Luzula, 51
Lycopodiaceae, 10
Lycopodium, 10
Lycopsida, 10
Lygodium, 12

Macradenia, 60