This year several plants seem to be flowering slightly ahead of schedule. In my garden (South Oxfordshire) we have had dry and hot weather for the last two weeks.
Suddenly all the tulips have come into flower at one time where normally a few open each day over a few weeks.
Right now the bees have a lot of choice as the hedgerows are still flowering, the fruit trees have started and the rape fields are just beginning to turn yellow. But still, quite a few of our bees had found this colourful display.
The pollen is mostly dark brown - almost black - and the bees were carrying such heavy loads that it was making their back legs dangle down with the weight.I was surprised they could even fly but they managed although I saw some who looked a bit wobbly. In this picture you can just see the black bulges on her legs hung low under her body.