Specialist Bees

Doug Tallamy has done a great job efforts to make lists of native plant genera that show the number of different caterpillar species each genus supports. Great, so now we all know to plant native oaks, cherries, willows, goldenrod, etc. But there is a lot more to supporting biodiversity than caterpillars. Take bees, for example. Of the roughly 4,000 or so native bees in the US and CA, somewhere around 30% are pollen specialists that require pollen from just one or a few plant genera to provision their young. The specialists appear more threatened than the generalists according to common sense and several research papers. So what do we do to support pollen specialist bees? Where is the list of native plant genera that shows the number of specialist bees that use pollen from that genus? Jarrod Fowler has done extensive literature searches to generate lists of plant genera that support specialist bees for the Eastern, Central, and Western US. Also, the National Wildlife Federation has a list that covers the Eastern US (including Tennessee) but many of those listed genera aren’t native to TN and in other cases support specialist bees that aren’t native to Tennessee.

So, how do we get a list for Tennessee? If you  copy/paste Jarrod’s table into your favorite spreadsheet,  use spreadsheet functions to count the number of occurrences of  “TN” for each genus, and delete the genera that show a zero, you get a list for Tennessee shown below. So, let’s get some Helianthus, Rudbeckia, Solidago, Verbesina, etc. in the ground! Our pollen specialist bee friends in Tennessee will thank us.