| 1991 : Hitachi, Ibaraki Pref. | |||
| TWTwNo | Family | Scientific Name | |
| 4279 | Pinaceae | Pinus densiflora Sieb. et Zucc. | |
| 4280 | Fagaceae | Quercus serrata Thunb. ex Murray | |
| 4281 | Betulaceae | Carpinus laxiflora (Sieb. et Zucc.) Bl. | |
| 4282 | Ericaceae | Pieris japonica (Thunb.) D. Don | |
| 4283 | Theaceae | Eurya japonica Thunb. | |
| 4284 | Rosaceae | Prunus jamasakura Sieb. ex Koidz. | |
| 4285 | Rosaceae | Prunus jamasakura Sieb. ex Koidz. | |
| 4286 | Betulaceae | Alnus firma Sieb. et Zucc. | |
| 4287 | Rosaceae | Prunus grayana Maxim. | |
| 4288 | Cornaceae | Aucuba japonica Thunb. | |
| 4289 | Leguminosae | Wisteria floribunda (Willd.) DC. | |
| 4290 | Clethraceae | Clethra barvinervis Sieb. et Zucc. | |
| 4291 | Ericaceae | Rhododendron kempferi Planch. | |
| 4292 | Cupressaceae | Chamaecyparis obtusa (Sieb. et Zucc.) Endl. | |
| 4293 | Caprifoliaceae | Weigela decora (Nakai) Nakai | |
| 4294 | Cornaceae | Cornus controversa Hemsl. | |
| 4295 | Taxodiaceae | Cryptomeria japonica D. Don | |
| 4296 | Caprifoliaceae | Sambucus sieboldiana Bl. | |
| 4297 | Euphorbiaceae | Mallotus japonicus (Thunb.) Muell. Arg. | |
| 4298 | Stachyuraceae | Stachyurus praecox Sieb. et Zucc. | |
| donated from the Ibaraki Nature Musem. 19 Dec. 2003 | |||
| Takahara, Juou Machi, Taga Gun, Ibaraki Pref. | |||
| 20763 | Rutaceae | Zanthoxylum schinifolium Sieb. et Zucc. | |
| 20768 | Saxifragaceae | Deutzia crenata Sieb. et Zucc. | |
| 20796 | Scrophulariaceae | Paulownia tomentosa (Thunb.) Steud. | |
| 20831 | Araliaceae | Aralia elata (Miq.) Seemann | |
| 20851 | Araliaceae | Kalopanax pictus (Thunb.) Nakai | |
| 20852 | Ulmaceae | Ulmus davidiana Planch. var. japonica (Rehder) Nakai | |