Pollen is a highly nutritious and well balanced food material containing protein, sizable amounts of starch, sugars, fat or oil, minerals, antioxidants and vitamins such as thiamin. It is also rich in free amino acids. There can be no doubt therefore about its value as a food for insects and mammals. It is clear that in floral biology, pollen plays a DUAL ROLE: it is an indispensable link in the reproductive cycle of many plants, but in many cases we see that some of it is also sacrificed as a food benefit for the pollinator. - Millet

CHRISTIAN KONRAD SPRENGEL - (22 September 1750 – 7 April 1816)
German theologist, teacher and, most importantly, a naturalist. The discoverer of the role of nectar guides that help pollinating insects find the nectar of flowers.

I am still intrigued why pollens can cause so much allergic reactions in spring time? I'm hard pressed to find any ecological reason why this happens to a lot of human beings.

Joe - ever suffering each spring time.

Because the outer wall of each tiny pollen grain is practically indestructible, pollen is easily recognizable even in soils that are millions of years old. Also the shape and size of the pollen grains, and the beautiful fine sculpturing which they often possess, are different for every plant species. A pollen grain is to a botanist what a fingerprint is to a detective. By looking at a single grain under a microscope, an expert can often decide immediately what flower species it came from. - Millet

There can be no doubt that on a global scale, bees (especially honey bees and bumblebees) are the most important pollinators. It has been calculated that in pre-war Germany alone, honey bees pollinated about TEN TRILLION flowers in the course of a single summer's day. To make 1-lb. of honey, bees have to visit about ten million blossoms. In North America there are about 5,000 species of bees, 100 different species having been counted on the single crop alfalfa. The weight of pollen collected by a single honey bee colony can be more than 64-lbs. in a year. Millet