Hypericum perforatum
Perforate St John's-wort
Hypericum pulchrum
Slender St John's-wort
Hypericum tetrapterum
Square-stalked St John's-wort
Hypochaeris maculata
Spotted Cat's-ear
Hypochaeris radicata
Cat's-ear
Hypopitys monotropa
Yellow Bird's-nest
Ilex aquifolium
Holly
Inula conyzae
Ploughman's-spikenard
Inula helenium
Elecampane
Iris foetidissima
Stinking Iris
Iris pseudacorus
Yellow Iris
Isoetes echinospora
Spring Quillwort
Isoetes lacustris
Quillwort
Jacobaea vulgaris
Common Ragwort
Juglans regia
Walnut
Juncus acutiflorus
Sharp-flowered Rush
Juncus acutus
Sharp Rush
Juncus articulatus
Jointed Rush
Juncus bulbosus
Bulbous Rush
Juncus compressus
Round-fruited Rush
Juncus effusus
Soft-rush
Juncus gerardii
Saltmarsh Rush
Juncus inflexus
Hard Rush
Juncus squarrosus
Heath Rush