Pollen is produced by the male seed plants, with the oldest pollen-producers being conifers and grasses and the youngest being the flowering plants we have in our gardens and allotments.
Honey bees collect pollen, carefully pack it onto their pollen baskets and carry it back to their nest where it is taken and pushed firmly into the cells closest to the eggs and larvae in the brood combs which us where it’s used as ‘bee bread’ for developing larvae. Pollen is a protein-rich food source, balancing out the carbohydrates in honey. A healthy colony may collect, and use, around 45kg (100 lbs) of pollen in a season sourced from a wide range of pollen producing plants within foraging distance. The benefit of this is that the developing larvae consume a broad variety of vitamins and minerals.
Beekeepers use pollen cards to match the colour of the pollen they can see on a bee’s legs to the flower source. It’s easy, though, to instantly see if a bee has collected pollen from Oil Seed Rape because it’ll have a little yellow dot in the middle of its head, whilst those collecting from Himalayan Balsam will look a bit like ghost bees.
Beekeepers sometimes collect and store pollen to feed back to their bees in early spring, to encourage brood laying and to increase the colony’s size before the first spring glut of pollen appears on Pussy Willows. This is so their colonies are ready to pollinate early flowering fruit, for example, apple orchards.
An interesting fact about pollen is that each species of plant’s pollen has a unique shape that will only fit onto the stigma of the female flowers – a bit like a small child’s shape sorter. Each pollen producing plant has its own unique genetic fingerprint, unless it’s a clone, and this can be used by scientists (Forensic Palynologists) to almost exactly date an event using pollen traces, both archaeologically and at a crime scene.