Click on the name of a different pollen below to find out more about it,
or click on the other microscope for a different view of this pollen.

Bur Oak Cattail Cocklebur Cottonwood
Dandelion Kentucky Bluegrass Pigweed Ragweed
River Birch Russian Thistle Sunflower White Pine

White Pine
Pinus strobus

When white pine forests bloom in spring, you can sometimes see spectacular columns of pollen rising up through the trees like smoke. Luckily, the pollen doesn't cause allergies in most people. Pine pollen is lightweight and shaped like a pair of wings. It can travel great distances, fertilizing trees far away. This is how vast pine forests once spread across the eastern United States and Canada. Some say that before European settlers arrived on the continent, a squirrel could travel its whole life in the trees without ever touching the ground. The early settlers saw these towering pines as valuable timber. Scientists estimate that the forests contained enough boards to wrap around the planet millions of times. By the late 1700s the forests had been cut down for ship masts, bridges, homes, and furniture. In the early 1900s, U.S. foresters began a program--called reforestation--to plant large numbers of young trees to renew the forests. White pines grow fast, and today they once again cover large areas of the Northeast. Without disturbance from humans, these towering trees can keep growing for hundreds of years. But once again they are threatened, this time by acid rain caused by urban pollution.