| Silphium integrifolium Michx. | | a | | Silphium integrifolium Michx. | | 33946 | |
| Silphium laciniatum L. | | a | | Silphium laciniatum L. | | 33947 | |
| Silphium perfoliatum L. | | a | | Silphium perfoliatum L. | | 33948 | |
| Silphium trifoliatum L. | | a | | Silphium trifoliatum L. | | 33949 | |
| Silphium trilobatum L. | Sphagneticola trilobata (L.) Pruski | | | Silphium trilobatum L. | Sphagneticola trilobata (L.) Pruski | 33950 | 409995 |
| Silphium spp. | | a | | Silphium spp. | | 405619 | |
| Silphium peristenium Raf. | Engelmannia peristenia (Raf.) Goodman & C. A. Lawson | | | Silphium peristenium Raf. | Engelmannia peristenia (Raf.) Goodman & C. A. Lawson | 418965 | 418964 |
| Silphium terebinthinaceum Jacq. | | a | | Silphium terebinthinaceum Jacq. | | 449883 | |
| Silphium compositum Michx. | | a | | Silphium compositum Michx. | | 449884 | |
| Silphium pumilum Michx. | Berlandiera pumila (Michx.) Nutt. | | | Silphium pumilum Michx. | Berlandiera pumila (Michx.) Nutt. | 458984 | 458983 |
| Silphium betonicifolia Hook. | Berlandiera ×betonicifolia (Hook.) Small | | | Silphium betonicifolia Hook. | Berlandiera betonicifolia (Hook.) Small | 458985 | 413042 |
| Silphium albiflorum A. Gray | | a | | Silphium albiflorum A. Gray | | 463822 | |
| Silphium radula Nutt. | | a | | Silphium radula Nutt. | | 465619 | |
| Silphium radula Nutt. var. radula | | a | i | Silphium radula Nutt. var.radula | | 465620 | |
| Silphium radula Nutt. var. gracile (A. Gray) Clevinger | | a | i | Silphium radula Nutt. var.gracile (A. Gray) Clevinger | | 465621 | |
| Silphium wasiotense Medley | | a | | Silphium wasiotense Medley | | 486332 | |