BirchThey grow throughout the continental U.S., except in the southernmost and westernmost states, and their pollen is very likely to trigger allergies.
ElmThis tree grows in all but the coldest northern parts of the continental U.S. and makes pollen in the fall.
CedarThere are about 70 different kinds of these trees and bushes, including juniper and cypress, and some of them can cause major allergy issues.
OakMany people are allergic to oak pollen, and because the trees are common in residential areas and parks.
PineThese evergreen trees found all over U.S. make a huge amount of pollen in the spring.
PoplarThey’re most likely to cause allergy issues in Minnesota and areas in the Southwest.
WalnutTheir pollen can be a big trigger for allergies, but it’s heavy and usually drops to the ground.
RagweedThis grows everywhere and may be the most common allergy trigger in North America.