All 89 bee plants
Bramble pollen
Rubus fruticosus
Greenish grey, in the grey range.
FloweringJune to August
PollenGood
NectarYes
SeasonSummer
WhereHedgerow, Waste and verge, Woodland
Every hedge and waste corner, giving a long and steady flow.

Easy to mistake for these
Closest pollen colours in our set, measured the same way the pollen identifier scores a match. Colour alone will not settle it, so check the flowering months and what is actually growing near your hives.
Out at about the same time
Saw a load like this going in?
Sample the colour against all 89 plants, then keep a forage record per hive.