 Kalmia latifolia (Mountain Laurel) - Pink Flowers |
 Kalmia latifolia (Mountain Laurel) - White Flowers |
 Krigia biflora (Two-Flowered Cynthia) |
 Lactuca canadense (Canada Lettuce) |
 Lactuca species (Blue Lettuce) |
 Lactuca species (Blue Lettuce) - Unopened Flower Heads |
 Laportea canadensis (Wood Nettle) |
 Lathyrus japonicus (Beach Pea) |
 Lathyrus palustris (Marsh Pea) |
 Leersia oryzoides (Rice Cut-Grass) |
 Leersia virginica (Virginia Cut-Grass) |
 Lepidium virginicum (Virginia Pepperweed) |
 Lespedeza capitata (Round-Headed Bush-Clover) |
 Lespedeza hirta (Hairy Bush-Clover) |
 Lespedeza repens (Creeping Bush-Clover) |
 Lespedeza violacea (Violet Bush-Clover) |
 Leucothoe fontanesiana (Mountain Dog-Hobble) |
 Leymus mollis (Dune Grass) |
 Liatris aspera (Rough Blazing-Star) |
 Liatris cylindracea (Cylindric Blazing-Star) |
 Liatris scariosa (Devil's-Bite Blazing-Star) |
 Liatris spicata (Dense Blazing-Star) |
 Liatris spicata (Dense Blazing-Star) - White Flowers |
 Liatris squarrosa (Scaly Blazing-Star) |
 Lilium canadense (Canada Lily) |
 Lilium superbum (Turk's-Cap Lily) |
 Lilium superbum (Turk's-Cap Lily) - Large Cluster |
 Lindera benzoin (Spicebush) |
 Lindernia dubia (Yellow-Seeded False Pimpernel) |
 Linnaea borealis (Twinflower) |
 Linum species (Yellow Flax) |
 Liparis liliifolia (Lily-Leaved Twayblade) |
 Liparis loeselii (Loesel’s Twayblade) |
 Lipocarpha micrantha (Small-Flowered Dwarf Bulrush) |
 Liriodendron tulipifera (Tulip-Tree) |
 Lithospermum canescens (Hoary Puccoon) |
 Lithospermum caroliniense (Hairy Puccoon) |
 Lobelia cardinalis (Cardinal-Flower) |
 Lobelia inflata (Indian-Tobacco) |
 Lobelia kalmii (Kalm's Lobelia) |
 Lobelia siphilitica (Great Lobelia) |
 Lobelia spicata (Spiked Lobelia) |
 Lonicera canadensis (Canada Honeysuckle) |
 Lonicera dioica (Mountain Honeysuckle) |
 Lonicera oblongifolia (Swamp Honeysuckle) |
 Ludwigia alternifolia (Smooth Seedbox) |
 Ludwigia palustris (Marsh Seedbox) |
 Ludwigia peploides (Primrose-Willow) |
 Lupinus perennis (Wild Lupine) |
 Lupinus perennis (Wild Lupine) - Pale Flowers |