Pyrrosia piloselloides
Dragon Scale Fern
Pyrus cordata
Plymouth Pear
Radermachera yunnanensis
Ramalina fastigiata
Raphanus raphanistrum
Wild Radish
Rhinanthus alectorolophus
European Yellow-rattle
Rhodiola rosea
Roseroot
Ricinus communis
Castor-oil-plant
Rivini humilis
Bloodberry
Rosa rubiginosa
Sweet-briar
Rubia peregrina
Wild Madder
Ruella simplex
Mexican Petunia
Ruellia tuberosa
Minnieroot
Rumex confertus
Russian Dock
Sabulina verna
Spring Sandwort
Sagina procumbens
Procumbent Pearlwort
Sagittaria sagittifolia
Arrowhead
Salix herbacea
Dwarf Willow
Salpichroa origanifolia
Cock's-eggs
Salvia involucrata
Rosy-leaf sage
Salvia leucanthe
Mexican Bush Sage
Salvia pratensis
Meadow Clary
Salvia splendens
Bonfire Salvia
Sambucus canadensis
American Elderberry