My bee group talks about the 'June gap'. This is is the period where the spring flowers end and forage becomes scarce.
Many of the bee group are in rural areas of Oxfordshire where Oil Seed Rape is the primary crop. There are gardens and some hedgerows left, but their pickings are slim. In the city this is mostly not the case.
In central Oxford there are numerous gardens which are planted to bloom throughout the summer. There are the many rivers where the Elder has been flowering through June and the Iris (Flag) has been blooming. These areas are prone to flooding and so are less likely to be built on or put to single-use agriculture. The city must be beautiful if you're a bee.
All the gardens and green spaces won't completely compensate for the end of the blossom on the big trees like Horse Chestnut. The evidence on the base board of my city hives shows this. The lumps of pollen which drop off the bees' legs are much smaller -- perhaps half the diameter of the lumps which fall in peak time. There is a greater variation in colour at this time -- bright oranges; occasional deep reds; a purple and even blue.
There are lots of flights too. This indicates that there's something to do. I don't know whether they're returning full of nectar or with just enough to make it worth the trip. They might be bringing water or propolis. Whichever it is they're busy.
As June wears on I see that the Blackberry is in flower. This provides good forage for a while. The pale grey pollen is already dominating the base board. The plants grow prolifically around Oxford. Their seeds are distributed by birds and the plants will suffer any soil type. They'll flower during June and some of July and produce fruit during August and into September. With the arrival of the Blackberry flowers I call an end to any June gap.