I remember that day! such a glorious spring for the bees and a lucky shot,
@chalyse, that there is a bulb--some kind of species crocus--wonderful little early spring cheer for all in places with winter, and I don't think they would be very perennial without it. But there is such a vast variety of flowering plants to feed the bees, I'm sure you could find one or two that would be pleasing to you, a magnet for them, and closer to the ground than the trees
and a lucky shot, 
