al. (2011) described first fossils for the prunoid genus Oemleria along with the oldest Prunus flowers. The Prunus flowers are complemented by leaf fossils representing five to six distinct morphotypes. Spiraea is known from an inflorescence with multiple flowers and leaves that are either from the genus or a closely related extinct type. The leaves frequently are preserved with a persistent stipule, a feature not found in modern Spiraea species. The firethorn genus Pyracantha and the South American genus Hesperomeles have been tentatively identified from leaves while Maloidea leaves belonging to either Malus or Pyrus have been found. Two distinct species of the Asian endemic genus Photinia are known, however only on of them Photinia pagae had been described as of 2007. The rosaceous genus Physocarpus had been reported by Hopkins and Wehr (1994) as also occurring in the formation, however subsequent examination of the fossils by Oh & Potter (2005) failed to find stellate trichomes which are a distinct feature of the genus. They noted the fossils might be stem Neillieae, the rose tribe containing both Physocarpus and Neillia, or possibly Rubus, Crataegus, or Ribes. Fossils of both Sorbus and Rhus species leaves showing evidence of being interspecies hybrids have been noted from the formation and Flynn, DeVore and Pigg (2019) described four species of sumac which formed multiple hybrids. Between three and four Trochodendraceae species that have been described from the Klondike Mountain Formation. Broadly circumscribed four species in three genera have been identified at Republic, Paraconcavistylon wehrii, Pentacentron sternhartae, Tetracentron hopkinsii, and Trochodendron nastae. Additionally the species Trochodendron drachukii is known from related Kamloops group shales at the McAbee Fossil Beds near Cache Creek, British Columbia. Manchester et al. 2018 noted that Tr. drachukii is likely the fruits of Tr. nastae, while Pe. sternhartae are likely the fruits of Te. hopkinsii. If fossils of the fruits and foliage in attachment are found, that would bring the species count down to three whole plant taxa. Additionally, the extinct genus Nordenskioldia is also known from the formation. The placement of Nordenskioldia is debated, with some treatments placing it into Trochodendraceae, while a 2020 analysis placed it outside of the crown-group Trochodendaceae. Wesley Wehr in 1994 reported Bignoniaceae seeds along with a single Rubiaceae fruit and an isolated Fabaceae leaf. An update of the floral list by Wehr and Manchester published in 1996 added an additional fifteen taxa identified from