Annual Burnet, Prairie Burnet, Western Burnet: Poteridium annuum (Synonyms: Poteridium occidentale, Sanguisorba annua, Sanguisorba occidentalis ) - Note: This taxon is recognized as Poteridium occidentale in Oregon. Annual or biennial herb with strong taproot and freely branched. Leafy stems from 20-60 cm high. Leaves pinnately compound and 3-8 cm long with up to 17 leaflets or segments which are narrowly linear. Inflorescence an ovoid to cylindrical spike up to 30 mm long and 5-7 mm thick.
Burnet Bloodwort, Fodder Burnet, Garden Burnet, Small Burnet: Poterium sanguisorba var. polygamum (Synonyms: Poterium balearicum, Poterium polygamum, Poterium sanguisorba ssp. muricatum, Sanguisorba minor, Sanguisorba minor ssp. balearicum, Sanguisorba minor ssp. muricata) - Native of Europe. Perennial herb with simple to branched stems from 20-60 cm high. Leaves basal and on stem, the latter almost as large as the former. Leaves pinnately compound with 9-17 oval to ovate-oblong leaflets, each 1-2 cm long. Leaflet margins coarsely toothed. Inflorescence a spherical to ovoid spike from 8-20 mm long and 10 mm thick.
Garden Burnet, Great Burnet, Marsh Burnet, Official Burnet: Sanguisorba officinalis (Synonyms: Poterium officinale, Sanguisorba microcephala, Sanguisorba officinalis ssp. microcephala) - Perennial herb of wet meadows and marshes at medium to high altitudes. Many basal leaves which are pinnately compound with 9-13 ovate to elliptical leaflets, each measuring1.5-3 cm long with serrate margins.