Do I have enough early nectar sources for pollinators?
Early blooming trees and shrubs provide most of the truly early nectar available. All those Maple trees, Salix, redbud, apple, crabapple, serviceberry, and fruit trees all provide abundant bloom very early. Many berry producing shrubs and canes also provide plentiful early blooms for pollinators emerging from hibernation and looking for an energy source. What blooms and how early in the year will depend on the climate in your area.
What about bulbs? Do any provide a real pollinator food source? Many do and like most plants the species rather than the hybrids will more likely serve this purpose. Galanthus nivalis, Crocus tommasinianus, Narcissus pseudonarcissus, chose those you have seen blooming where the stamens are readily visible and loaded with pollen.
This iris reticulata is blooming in our garden in Chicago now in March.
A native north eastern Dwarf iris that blooms early is iris cristata. Both are visited by bees stimulated to search for food on warm sunny days.
And we always grow a few dandelions...
Flowers for pollinators
Prairie plants A-H
Prairie plants I-Z