In natural communities, plants of different species frequently exchange pollen. This heterospecific pollen transfer (HPT) is well-known to decrease seedset in the maternal species, though the mechanism of seedset reduction remains elusive. Although there is significant data on both heterospecific pollen deposition and seedset reduction following HPT in a variety of systems, to date, we have a limited understanding of the fate of heterospecific pollen following deposition, especially with regard to whether heterospecific pollen will germinate and grow pollen tubes into a stigma and style. I investigated the fate of heterospecific pollen tubes in an alpine plant community, where pollen is frequently exchanged due to geography and short growing seasons, meaning many angiosperms flower close to each other at the same time, creating high potential for pollinator sharing. I conducted experimental crosses using semi-in vivo pollination assays using 9 species that span a spectrum of genetic distance. I show that pollen tubes germinate and grow through styles in 93.6% of cases, even when crosses are phylogenetically distant (more than 60my divergent). I additionally collected RNA from conspecific and heterospecific crosses, and show that there is a quantitatively and qualitatively distinct stylar response to con- and heterospecific pollen. These results suggest that heterospecific pollen tube growth constitutes a potentially ecologically and evolutionary significant plant-plant interaction occurring in natural plant communities, and may be of especially high importance in systems where pollinator sharing and pollinator exchange are relatively high, like in alpine meadows.