Pollination Canada


Pollen is a white, yellow, or brown powder-like substance that is produced on the anthers of the flower, the male part of the plant. Pollen is used to fertilize the plant by the process of pollination, which is the transfer of pollen from the anthers to the flower's stigma, the female part of the plant. Pollination produces fruit and seed. Pollen also contains the plants genetic code.

There are two types of pollen: light, dusty pollen and heavy, sticky pollen. Light pollen grains can be airborne and blown in the wind for long distances. Plants with light pollen, for example grasses and corn, are wind-pollinated.

Pollen that is heavy and sticky cannot blow in the wind and therefore must be carried from flower to flower by insects, a process called insect pollination. Such plants must make sure that one insect does not take too much pollen in one visit and not leave anything for the next insect visitor. Many flowers force insects to come in contact with pollen while foraging for nectar by positioning the anthers in such a place that the insects, for example bees, will brush up against them. The pollen grains will stick the body of the insect, especially if it is hairy. Some parts of the body cannot be easily groomed, keeping the pollen from being put in pollen baskets. This ensures the transfer of pollen when the insects visit other flowers.

Pollen: Bee Nutrition

For most insects, pollen is secondary to nectar as a floral food reward. Pollen is a vital food source to pollinators and also bee larvae. Pollen is very rich in protein, containing 7-35% protein, as well as starch, vitamins, enzymes and pigments. Some plants do not produce nectar, and their pollen can be rich in lipids, including sterols, which are the building blocks of hormones and pheromones.

Pollen and Allergies

Allergies caused by pollen are commonly referred to as hay fever. Hay fever is the most common allergic disease. 1 One can only be allergic to the light and dusty pollen that is airborne, from wind-pollinated plants (trees, shrubs, weeds and grasses). The only way to have an allergic reaction to pollen from insect-pollinated plants is by direct contact.

Pollen normally enters the body via the nose and throat. The body's immune system produces antibodies that fight against the antigens. Powerful inflammatory chemicals are produced, which act on tissues in various parts of the body, for example the respiratory system, causing allergy symptoms. 2 Different kinds of pollen appear in the air during different times of the year, making pollen allergies seasonal. Some examples of trees that release pollen into the air are the maple, willow, birch, ash, oak, and pine. Examples of grasses and weeds include ragweed, russian thistle, sageweed, plantain, and nettle.3

It is difficult to avoid airborne pollen. Pollen counts, given by local weather reports, is a measure of how much pollen is present in the air. It is a general guide for when it is better to stay indoors to avoid contact with pollen.

  1. Medicinenet.com http://www.medicinenet.com/script/main/art.asp?articlekey=20277
  2. Aerobiology Research Laboratories. http://www.pollenplus.com/index.html
  3. Aerobiology Research Laboratories.http://www.pollenplus.com/pollen/pollen-index.html

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