Writing this from Dallas, Texas one of the ragweed hotspots of the nation, I'm particularly aware of "allergies" and the havoc they can cause. Here are some facts about allergies:

More than 50 million Americans suffer from allergies. Ragweed pollen is probably the largest single seasonal allergen in North America. It is estimated that one square mile of ragweed plants would release 16 tons of pollen in one season. Even skin contact with ragweed can cause dermatitis.

An allergy is