Doug Tallamy has done a great job making 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 Canada, somewhere around 30% are pollen specialists that require pollen from just one or a few plant genera to provision their young (USGS). 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 create 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 Central US 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 find there are 76 species of native specialist bees that utilize pollen from plants native to Tennessee, and here are their favorite genera.
Plant Genera and the Number of Specialist Bee Species Supported
| Genus | Common Name | Family | Number |
| Helianthus L. | Sunflowers | Asteraceae | 19 |
| Rudbeckia L. | Coneflowers (Susans) | Asteraceae | 16 |
| Solidago L. | Goldenrods | Asteraceae | 14 |
| Symphyotrichum Nees | American Asters | Asteraceae | 11 |
| Coreopsis L. | Tickseeds | Asteraceae | 10 |
| Grindelia Willd. | Gumweeds | Asteraceae | 9 |
| Verbesina L. | Crownbeards | Asteraceae | 9 |
| Bidens L. | Beggarticks | Asteraceae | 8 |
| Erigeron L. | Fleabanes | Asteraceae | 7 |
| Vaccinium L. | Blueberries | Ericaceae | 7 |
| Salix L. | Willows | Salicaceae | 6 |
| Silphium L. | Rosinweeds | Asteraceae | 6 |
| Vernonia Schreb. | Ironweeds | Asteraceae | 6 |
| Cirsium Mill. | Thistles | Asteraceae | 5 |
| Eurybia (Cass.) Cass. | Wood Asters | Asteraceae | 5 |
| Ratibida Raf. | Prairie Coneflowers | Asteraceae | 5 |
| Chrysopsis (Nutt.) Elliot | Golden Asters | Asteraceae | 4 |
| Heterotheca Cass. | Golden Asters | Asteraceae | 4 |
| Baccharis L. | Salt Bushes | Asteraceae | 3 |
| Gaillardia Foug. | Blanket Flowers | Asteraceae | 3 |
| Phacelia Juss. | Scorpionweeds | Boraginaceae | 3 |
| Potentilla L. | Cinquefoils | Rosaceae | 3 |
| Senecio L. | Ragworts | Asteraceae | 3 |
| Cornus (Swida) L. | Dogwoods | Cornaceae | 2 |
| Echinacea Moench | Coneflowers | Asteraceae | 2 |
| Euthamia Nutt. ex Cass. | Goldentops | Asteraceae | 2 |
| Fragaria L. | Strawberries | Rosaceae | 2 |
| Helenium L. | Sneezeweeds | Asteraceae | 2 |
| Heliopsis Pers. | Early Sunflowers | Asteraceae | 2 |
| Lyonia Nutt. | Staggerbushes | Ericaceae | 2 |
| Pyrrhopappus DC. | Desert Chicories | Asteraceae | 2 |
| Arabis L. | Rockcresses | Brassicaceae | 1 |
| Calystegia R. Br. | Bindweeds | Convolvulaceae | 1 |
| Cardamine L. | Toothworts | Brassicaceae | 1 |
| Ceanothus L. | New Jersey Teas | Rhamnaceae | 1 |
| Cercis L. | Redbuds | Fabaceae | 1 |
| Claytonia L. | Spring Beauties | Montiaceae | 1 |
| Cucurbita L. | Squashes | Cucurbiteae | 1 |
| Erythronium L. | Trout Lilies | Liliaceae | 1 |
| Gaylussacia Kunth | Huckleberries | Ericaceae | 1 |
| Geranium L. | Cranesbills | Geraniaceae | 1 |
| Heuchera L. | Alumroots | Sacifragaceae | 1 |
| Hibiscus L. | Mallows | Malvaceae | 1 |
| Hieracium L. | Hawkweeds | Asteraceae | 1 |
| Hydrophyllum L. | Waterleafs | Boraginaceae | 1 |
| Ilex L. | Hollies | Aquifoliaceae | 1 |
| Ipomoea L. | Morning Glories | Convolvulaceae | 1 |
| Krigia Schreb. | Dwarf Dandelions | Asteraceae | 1 |
| Lupinus L. | Lupines | Fabaceae | 1 |
| Lysimachia L. | Loosestrifes | Primulaceae | 1 |
| Monarda L. | Bee Balms | Lamiaceae | 1 |
| Nemophila Nutt. | Baby Blue Eyes | Boraginaceae | 1 |
| Oenothera L. | Evening Primroses | Onagraceae | 1 |
| Packera Á. Löve & D. Löve | Groundsels | Asteraceae | 1 |
| Penstemon Schmidel | Beardtongues | Plantagiinaceae | 1 |
| Physalis L. | Groundcherries | Solanaceae | 1 |
| Pityopsis Nutt. | Silkgrasses | Asteraceae | 1 |
| Rhododendron L. | Rhododendrons | Ericaceae | 1 |
| Rubus L. | Blackberries | Rosaceae | 1 |
| Viola L. | Violets | Violaceae | 1 |
| Waldsteinia Willd. | Barren Strawberries | Rosaceae | 1 |
| Zizia W.D.J. Koch | Alexanders | Apiaceae | 1 |