Bumble bees are sweet, gentle, and some people think they are the cutest of all bees.

A recently published academic paper authored by Cole, Jerry S and Siegel, Rodney B, pinpoints a few plants that are particularly popular with some of the many bumble bee species (Bombus Latreille).

The study did not differentiate whether the flowers were chosen by bumblebees for pollen or nectar or both, so caution is advised in drawing too many conclusions.

Plant diversity in a rich and diverse landscape of wildflowers in meadows is essential for healthy bumble bees.

In small private gardens and cityscapes, where there isn't much room for those that want to help bumblebees, planting a few of these flowers can be beneficial. There are many qualifiers involved in why these flowers were chosen. Just know that these are not the only flowers for bumble bees. 

This 2:41-minute video shows bumblebees enjoying luscious lupine flowers.

The subject of this study by Cole, Jerry S and Siegel, Rodney B was the bumble bee (Hymenoptera: Apidae) in the florally diverse meadows of the montane Riparian Habitat of California. Bumble bees were surveyed between May and August of 2015 and 2016 on Plumas National Forest in the northern Sierra Nevada in California, mostly between 9 am and 5 pm, at 413 bumble bee sampling plots.

The assessment was made over two summers, one with normal rainfall and the other with low precipitation. The first year followed the winter with the lowest snow pack in 120 years following a multi-year drought. The second year followed a more average winter.

The five most captured bumble bee species each selected at least one unique plant species, but there were overlaps. The study finds that maintaining, seeding, or planting these plants may benefit these bumble bees.

The two most popular plant species were Oregon checker-mallow (Sidalcea oregana) and mountain pennyroyal (Monardella odoratissima) flowers.

Bombus vosnesenskii is called the yellow-faced bumble bee and favored large-leafed lupine (Lupinus polyphyllus). The species stayed loyal to this plant even when other flowers were more prevalent. 

Nettleleaf sage or horsemint (A. urticifolia) was favored by bumble bee species B. flavifrons. In addition, B. bifarius and B. melanopygus strongly selected thick stemmed asters (Eurybia integrifolia) and long stalk clover (Trifolium longipes) and Ryderberg's penstemon (P. rydbergii) from the snapdragon family.

The study resulted in 1243 bumble bees of 13 species being captured and identified during 807 surveys on 413 plots in 2015. The 3 most frequently captured species were B. bifarius (367 captures), B. flavifrons (301 captures), and B. vandykei (156 captures).

In 2016, there were 3612 bumble bees of 13 species captured and identified in 818 surveys on 410 plots, dominated by B. vosnesenskii (2641 captures) then B. flavifrons (349 captures) and B. melanopygus (268 captures).

Bumble bees, like honeybees, are challenged in so many ways these days. Adding a few of these flowers to your garden may make the lives of some local bumblebees easier and more enjoyable.