How can I confirm I have ragweed? Does it spread by underground roots?

Answer 1

here are a few links that might help you!
http://www.pq.lung.ca/sections/mpulmonaires/en/herbe/index.php
http://web1.msue.msu.edu/msue/iac/e1363/e1363.htm(number22,almost at the bottom,description and pictures)
hope this helps!and you get rid of it with weed killers,like round up found at walmart and other gardening stores!

Answer 2

It really depends on how vunerable to the allergy you are, it is normally however an airborn allergy, from the pollen of the plant flying through the air, my dad and sister both get severe ragweed reactions.