Wind and Water Pollination
Many flowers are pollinated without the aid of animals (insect, bird, or mammal). Here are a few examples.
Most conifers and about 12% of the world’s flowering plants are wind-pollinated. They include grasses and their cultivated cousins, the cereal crops; many trees; the infamous allergenic ragweeds; and others. All release billions of pollen grains into the air so that a lucky few will hit their targets.
Clouds of pollen rise above an Engelmann spruce forest. Photo by Al Schneider.
Wind-pollinated flowers are typically:
- No bright colors, special odors, or nectar
- Most have no petals
- Stamens and stigmas exposed to air currents
- Large amount of pollen
- Pollen smooth, light, easily airborne
- Stigma feathery to catch pollen from wind
- May have staminate and pistillate flowers, may be monoecious or dioecious
- Usually single-seeded fruits, such as oak, grass, birch, poplar, hazel, dock, cat-tail, plantain, and papyrus
Pollen can also float on the water’s surface drifting until it contacts flowers. This is called surface hydrophily and is relatively rare. This water-aided pollination occurs in waterweeds and pondweeds. In a very few cases, pollen travels underwater.
Many of the water-pollinated plants have become invasive throughout the United States. To learn more, visit these invasive species websites: