19. Greensboro, North Carolina

Greensboro is ranked on the list for having average overall pollen levels, receiving a 76.76-point ranking, the study reported.
Weed pollen is a top component here and is reported to affect allergies year-round but peaks in April. Greensboro has a worse-than-average rate for the amount of medicine used and a worse-than-average ranking for the number of people who ultimately need to seek specialist care.