| Veronica agrestis | GB, VC6 North Somerset, Hallatrow | Ida Mary Roper | Botanical Exchange Club of The British Isles Ida Mary Roper George Claridge Druce | 25/6/1930 | K |
| Veronica agrestis | GB, VC6 North Somerset, Hallatrow | Ida Mary Roper | Isaac A Helsby | 25/6/1930 | SLBI |
| Verbascum chaixii subsp. chaixii | GB, VC34 West Gloucestershire, Ashton Gate | Ida Mary Roper | Ida Mary Roper | 26/7/1909 | K |
| Verbascum blattaria | GB, VC34 West Gloucestershire, Henbury | Ida Mary Roper | Watson Botanical Exchange Club Ida Mary Roper | 16/8/1913 | SLBI |
| Verbascum blattaria | GB, VC34 West Gloucestershire, Henbury | Ida Mary Roper | Watson Botanical Exchange Club Arthur George Gregor Ida Mary Roper | 16/8/1913 | K |
| Verbascum blattaria | GB | Ida Mary Roper | | 16/8/1913 | SLBI |
| Verbascum | GB, VC6 North Somerset, Ashton Gate | Ida Mary Roper | Watson Botanical Exchange Club Ida Mary Roper William Robert Sherrin | 26/7/1909 | SLBI |
| Ulmus minor subsp. angustifolia | GB, VC6 North Somerset, Wraxall | Ida Mary Roper | Watson Botanical Exchange Club Ida Mary Roper | 3/3/1926 13/4/1926 26/7/1926 | SLBI |
| Trifolium hybridum | GB, VC34 West Gloucestershire, Avonmouth Docks, Bristol | Ida Mary Roper | Watson Botanical Exchange Club | 11/8/1920 | SLBI |
| Trifolium dubium | GB, VC6 North Somerset, Bristol | Ida Mary Roper | Watson Botanical Exchange Club William Robert Sherrin | 28/5/1915 | SLBI |
| Tragopogon pratensis subsp. minor | GB, VC6 North Somerset, Cleeve | Harold Stuart Thompson Ida Mary Roper | Harold Stuart Thompson | 6/8/1930 | BIRM |
| Torilis nodosa | GB, VC34 West Gloucestershire, Avonmouth | Ida Mary Roper | Watson Botanical Exchange Club Harold Stuart Thompson Ida Mary Roper | 26/9/1927 | BIRM |
| Thymus serpyllum | GB, VC6 North Somerset, Weston-super-Mare | Ida Mary Roper | William Robert Sherrin | 5/8/1915 | SLBI |
| Thymus chamaedrys | GB, VC6 North Somerset, Tickenham Hill | Ida Mary Roper | Botanical Exchange Club of The British Isles Ida Mary Roper Lester Vallis Lester-Garland | 1/9/1922 | K |
| Teucrium scorodonia | IE, VCH21 Co. Dublin, Howth | Ida Mary Roper | Ida Mary Roper | 23/9/1925 | K |
| Taraxacum | GB, VC34 West Gloucestershire, Avonmouth | Ida Mary Roper | Botanical Exchange Club of The British Isles Ida Mary Roper Job Edward Lousley | 28/4/1927 | SLBI |
| Taraxacum | GB, VC34 West Gloucestershire, Westbury on Trym | Ida Mary Roper | Botanical Exchange Club of The British Isles Ida Mary Roper Job Edward Lousley | 5/5/1927 | SLBI |
| Symphytum tuberosum | GB, VC34 West Gloucestershire, Compton Greenfield | Ida Mary Roper | Watson Botanical Exchange Club Ida Mary Roper | 11/5/1921 | SLBI |
| Symphytum tuberosum | GB, VC34 West Gloucestershire, Compton Greenfield | Ida Mary Roper | Harold Stuart Thompson | 11/5/1921 | BIRM |
| Symphytum officinale x asperum = S. x uplandicum | GB, VC6 North Somerset, Gatcombe | Ida Mary Roper | Botanical Society & Exchange Club of The British Isles Charles Bailey James Walter White | 23/5/1918 | MANCH |
| Symphytum officinale x asperum = S. x uplandicum | GB, VC6 North Somerset, Gatcombe Mill | Ida Mary Roper | Botanical Society & Exchange Club of The British Isles Charles Bailey Ida Mary Roper | 28/5/1915 | MANCH |
| Symphytum | GB, VC6 North Somerset, Gatcombe Mill | Ida Mary Roper James Walter White | Watson Botanical Exchange Club | 23/5/1918 | SLBI |
| Symphytum | GB, VC6 North Somerset, Wraxall | James Walter White | Ida Mary Roper | 11/6/1932 | SLBI |
| Sorbus minima | GB, VC42 Breconshire, Craig Cille | Ida Mary Roper | Ida Mary Roper | 7/6/1927 24/8/1927 | BIRM |
| Sonchus asper | GB, VC34 West Gloucestershire, Wickwar | Ida Mary Roper | Watson Botanical Exchange Club Job Edward Lousley | 20/7/1927 | SLBI |
| Sonchus asper | GB, VC34 West Gloucestershire, Wickwar | | Watson Botanical Exchange Club Ida Mary Roper Isaac A Helsby | 20/7/1927 | SLBI |
| Sisymbrium hispanicum | GB, VC34 West Gloucestershire, Bristol, Saint Philip's Marsh | Ida Mary Roper | Watson Botanical Exchange Club Augustin Ley Ida Mary Roper | 30/6/1909 | BIRM |
| Silene dioica | GB, VC34 West Gloucestershire, Hallen | Ida Mary Roper | Watson Botanical Exchange Club Ida Mary Roper | 15/5/1922 | SLBI |
| Silene conica | GB, VC26 West Suffolk, Thetford | Ida Mary Roper | Harold Stuart Thompson | 6/6/1922 | BIRM |
| Senecio vulgaris | GB, VC6 North Somerset, Kewstoke | Ida Mary Roper | Watson Botanical Exchange Club Ida Mary Roper | 29/4/1918 | SLBI |
| Senecio vulgaris var. radiatus | GB, VC6 North Somerset, Portishead | Ida Mary Roper | Watson Botanical Exchange Club Augustin Ley | 22/5/1909 | BIRM |
| Scutellaria altissima | GB, VC6 North Somerset, Mells | Ida Mary Roper | Watson Botanical Exchange Club Ida Mary Roper Job Edward Lousley | 9/7/1932 | SLBI |
| Schoenus nigricans | GB, VC6 North Somerset, Churchill | Ida Mary Roper | | 24/7/1919 | BIRM |
| Sambucus nigra | GB, VC6 North Somerset, Weston in Gordano | Ida Mary Roper | Watson Botanical Exchange Club Ida Mary Roper | 28/9/1918 | SLBI |
| Sambucus nigra | GB, VC6 North Somerset, Weston in Gordano | Ida Mary Roper | Watson Botanical Exchange Club Harold Stuart Thompson | 28/9/1918 | BIRM |
| Salix viminalis x caprea = S. x smithiana | GB, VC6 North Somerset, Pensford | Ida Mary Roper | Botanical Exchange Club of The British Isles Ida Mary Roper J Fraser Spencer Henry Bickham | 30/3/1927 to 22/6/1927 | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC6 North Somerset, Walton-in-Gordano | Ida Mary Roper | Joseph Edward Little | 9/4/1913 7/8/1913 | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC34 West Gloucestershire, Westerleigh | Ida Mary Roper | Watson Botanical Exchange Club Ida Mary Roper | 20/4/1921 17/8/1921 | SLBI |
| Salix viminalis x caprea = S. x smithiana | GB, VC34 West Gloucestershire, Westerleigh | Ida Mary Roper | Watson Botanical Exchange Club Ida Mary Roper | 20/4/1921 17/8/1921 | CGE |
| Salix triandra x viminalis = S. x mollissima | GB, VC6 North Somerset, Corston | Ida Mary Roper | Ida Mary Roper | 24/4/1915 | CGE |