| Salix viminalis x caprea = S. x smithiana | IE, VCH21 Co. Dublin, Balbriggan | M O'Leary | | 19/8/1934 | DBN |
| Mentha aquatica x spicata = M. x piperita | IE, VCH11 Co. Kilkenny, Castlecomer | Robert Albert Phillips | | 27/8/1933 | DBN |
| Salix cinerea subsp. oleifolia | IE, VCH39 Co. Antrim, Glendun Viaduct | Arthur Wilson Stelfox | | 30/7/1931 | DBN |
| Salix cinerea x myrsinifolia = S. x strepida | IE, VCH39 Co. Antrim, Glendun Viaduct | Arthur Wilson Stelfox | | 30/7/1931 | DBN |
| Salix cinerea x myrsinifolia = S. x strepida | IE, VCH39 Co. Antrim, Glendun Viaduct | Arthur Wilson Stelfox | | 30/7/1931 | DBN |
| Salix viminalis x caprea = S. x smithiana | IE, VCH27 West Mayo, Westport | Matilda Cullen Knowles | National Museum Ireland Matilda Cullen Knowles | 4/7/1909 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH8 Co. Limerick, West Ardagh | Matilda Cullen Knowles | Science & Art Museum Dublin | 9/1908 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH9 Co. Clare, Killadysart | Matilda Cullen Knowles | Dublin Museum Matilda Cullen Knowles | 8/1907 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH8 Co. Limerick, Foynes | Charlotte Grace O'Brien | Science & Art Museum Dublin | 8/1906 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH30 Co. Cavan, Annagh Lough | Robert Lloyd Praeger | | 9/8/1905 | DBN |
| Mentha arvensis x spicata = M. x gracilis | IE, VCH30 Co. Cavan, Cavan | Robert Lloyd Praeger | Science & Art Museum Dublin Robert Lloyd Praeger | 9/8/1905 | DBN |
| Mentha arvensis x spicata = M. x gracilis | IE, VCH30 Co. Cavan, Cavan | Robert Lloyd Praeger | Robert Lloyd Praeger | 9/8/1905 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH30 Co. Cavan, Annagh Lough | Robert Lloyd Praeger | Robert Lloyd Praeger | 8/1905 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH30 Co. Cavan, Lough Oughter | Robert Lloyd Praeger | National Museum Ireland Robert Lloyd Praeger | 8/1905 | DBN |
| Mentha aquatica x spicata = M. x piperita | IE, VCH36 Tyrone, Coalisland Canal | R W Bingham | Robert Lloyd Praeger | 8/1905 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH9 Co. Clare, Edenvale | Robert Donough O'Brien | Science & Art Museum Dublin | 26/8/1904 | DBN |
| Salix viminalis x cinerea = S. x holosericea | IE, VCH8 Co. Limerick, Loghill | Matilda Cullen Knowles | Science & Art Museum Dublin | 6/1904 | DBN |
| Salix viminalis x caprea = S. x smithiana | IE, VCH8 Co. Limerick, West Loghill | Matilda Cullen Knowles | Science & Art Museum Dublin | 6/1904 | DBN |
| Mentha arvensis x aquatica x spicata = M. x smithiana | IE, VCH21 Co. Dublin, Rathfarnham | Robert Lloyd Praeger | Robert Lloyd Praeger | 9/1903 | DBN |
| Mentha arvensis x aquatica x spicata = M. x smithiana | IE, VCH21 Co. Dublin, Rathfarnham | Robert Lloyd Praeger | Robert Lloyd Praeger | 9/1903 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, Kerry, Killarney | Reginald Wiliam Scully | Reginald Wiliam Scully | 27/8/1903 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH1 South Kerry, Home Park, Killarney | Reginald Wiliam Scully | Reginald Wiliam Scully | 24/7/1903 | DBN |
| Mentha aquatica x spicata = M. x piperita | IE, VCH8 Co. Limerick, White River | Matilda Cullen Knowles | Science & Art Museum Dublin | 6/1903 | DBN |
| Salix viminalis x caprea = S. x smithiana | IE, VCH36 Tyrone | Matilda Cullen Knowles | Science & Art Museum Dublin | 9/1900 | DBN |
| Salix viminalis x caprea = S. x smithiana | IE, VCH36 Tyrone, Foyle | Matilda Cullen Knowles | Science & Art Museum Dublin | 9/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH36 Tyrone, Strabane Canal | | Science & Art Museum Dublin | 9/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH29,VCH30, Garadice Lough | Robert Lloyd Praeger | Robert Lloyd Praeger | 21/8/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH25 Co. Roscommon, Lough Ree | Robert Lloyd Praeger | Robert Lloyd Praeger | 21/8/1900 | DBN |
| Mentha aquatica x spicata = M. x piperita | IE, VCH25 Co. Roscommon, Slieve Bawn | Robert Lloyd Praeger | Robert Lloyd Praeger | 21/8/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH25 Co. Roscommon, Slieve Bawn | Robert Lloyd Praeger | Science & Art Museum Dublin Robert Lloyd Praeger | 21/8/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH29 Co. Leitrim, Garadice Lough | Robert Lloyd Praeger | Science & Art Museum Dublin Robert Lloyd Praeger | 21/8/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH24 Co. Longford, Ballymahon | Robert Lloyd Praeger | Robert Lloyd Praeger | 19/8/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH24 Co. Longford, River Tang, mouth of | Robert Lloyd Praeger | Robert Lloyd Praeger | 19/8/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH24 Co. Longford, River Tang, mouth of | Robert Lloyd Praeger | Robert Lloyd Praeger | 19/8/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH24 Co. Longford, Ballymahon | Robert Lloyd Praeger | Robert Lloyd Praeger | 18/8/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH10 North Tipperary, Cloughjordan | Robert Lloyd Praeger | Robert Lloyd Praeger | 12/8/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH25 Co. Roscommon, Slieve Bawn | Robert Lloyd Praeger | Robert Lloyd Praeger | 2/8/1900 | DBN |
| Salix purpurea x viminalis x cinerea = S. x forbyana | IE, Mayo, Foxford | Robert Lloyd Praeger | Robert Lloyd Praeger | 30/7/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH27 West Mayo, Lough Conn | Robert Lloyd Praeger | Robert Lloyd Praeger | 27/7/1900 | DBN |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH27 West Mayo, Lough Conn | Robert Lloyd Praeger | | 27/7/1900 | DBN |