Changes in flora by the encroachment of non-native plants are widespread. However, little is known about how bees respond to the increase in non-native flora. Understanding the role non-native plants play in the diets of native bees could be important to conserving plants and bees as well as predicting how the continual spread of non-native plants could impact bee demographics.  In order to assess how generalist native bees use native and non-native plants pollen loads were removed from native Bombus vosnesenskii and analyzed to determine composition.  We also determined the overall prevalence of each flowering plant species and recorded morpological characteristics of plants known to be used by Bombus.  The prevalence data and pollen load data are used to estimate preference of pollen types. Additional data on pollinator visitation, breeding system and pollen protein and load were recorded. Results/Conclusions

While all pollen loads contain some non-native pollen, B. vosnesenskii show a strong preference for native pollens. This strong preference is particularly remarkable given that native flowers are outnumbered by invasive flowers in all sites by at least 2:1.Thus as non-native plants continue to spread this species could suffer demographic consequences. Comparisons of the plants chosen by B.vosnesenskii also allowed us to better understand the mechanisms behind the choice to incorporate non-native plants. This study allowed us to determine native plants that B.vosnesenskii use and that can be incorporated in pollinator specific restoration efforts. In the future we hope to look into how incorporating our finding into hedgerow establishment improves Bombus abundance in agricultural land.