So you think goldenrod causes hay fever? Read on to find out the truth about hay fever.

For a long time people believed that goldenrod was the cause of hay-fever, but scientists have discovered that this was a classic case of correlation not implying causality. Correlation is when two things come together. Causality is when one thing brings about another thing. They aren't always the same. So, for example, people suffer from hay-fever at the same time that goldenrod blooms. But it doesn't follow that goldenrod causes hay-fever.

We can tell by understanding how the body works. Allergic reactions are caused by inhaling pollen. Pollen becomes stuck in the tissues of your sinuses. Your body responds to this irritation by producing histamines, which cause inflammation, runny nose, and red eyes. We know that goldenrod isn't releasing pollen because goldenrod pollen doesn't travel through the air. The goldenrod relies on bees and other insects to carry its pollen around.

Ragweed is actually the plant responsible for all the pollen in the air. Nobody notices ragweed because it doesn't have big, eye-catching blossoms the way goldenrod does.