''Petrophytum'' ( orth. var. ''Petrophyton'') is a small genus of plants in the

rose family Rosaceae (), the rose family, is a family of flowering plants that includes 4,828 known species in 91 genera. The name is derived from the type genus ''Rosa''. The family includes herbs, shrubs, and trees. Most species are deciduous, but some ...

known as the rock spiraeas or rockmats. These are low mat-forming shrubs which send up erect stems bearing spike inflorescences of flowers. The brushy flowers are white and have many

stamen The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...

s and hairy, thready

pistil Gynoecium (; ; : gynoecia) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl (botany), whorl of a flower; it consists ...

s. Rockmats are native to western North America. Species: *'' Petrophytum caespitosum'' — mat rock spiraea *'' Petrophytum cinerascens'' — halfshrub rockmat, Chelan rockmat *'' Petrophytum hendersonii'' — Olympic Mountain rockmat

References

External links

Jepson Manual TreatmentUSDA Plants ProfileThe Plant List: A Working List of All Plant Species
Spiraeeae Rosaceae genera {{amygdaloideae-stub