| Wahlenbergia marginata (Thunb.) A.DC. | map | images (1) (2) |
| Waldsteinia fragarioides (Michx.) Tratt. | map | |
| Waldsteinia lobata (Baldw.) Torr. & Gray | map | |
| Warea cuneifolia (Muhl. ex Nutt.) Nutt. | map | images (1) (2) (3) (4) |
| Wisteria floribunda (Willd.) DC. | map | |
| Wisteria frutescens (L.) Poir. | map | images (1) (2) (3) (4) |
| Wisteria sinensis (Sims) DC. | map | images (1) (2) |
| Wolffia brasiliensis Weddell | map | |
| Wolffia columbiana Karst. | map | |
| Wolffiella gladiata (Hegelm.) Hegelm. | map | |
| Woodsia obtusa (Spreng.) Torr. | map | |
| Woodwardia areolata (L.) T. Moore | map | images (1) (2) |
| Woodwardia virginica (L.) Sm. | map | |