Medically Reviewed by Jabeen Begum, MD on March 13, 2024
Birch

Birch

1/15

If it’s spring and you’re sneezing, these trees might be part of the problem. They grow throughout the continental U.S., except in the southernmost and westernmost states, and their pollen is very likely to trigger allergies. They’re often planted in yards and other landscaping because people like the way they look -- the telltale white bark makes them easy to spot.

Elm

Elm

2/15

This tree grows in all but the coldest northern parts of the continental U.S. and makes pollen in the fall. The American elm, once common in the East and Midwest, has been steadily dying out since the outbreak of Dutch elm disease in Ohio in 1930. But the sturdy Chinese elm has stepped in. It grows to 40 to 60 feet tall with a full oval crown.  

Cedar

Cedar

3/15

There are about 70 different kinds of these trees and bushes, including juniper and cypress, and some of them can cause major allergy issues. Because there are so many types -- and they’re fairly common -- it can be hard to know which ones are your troublemakers. And their pollen season is long, too. It starts in January, and some of these trees and bushes can make pollen until May or June.

Oak

Oak

4/15

This tree grows all over the country and makes pollen in the spring. Many people are allergic to oak pollen, and because the trees are common in residential areas and parks, there can be a ton of it floating through the air. That can cause serious reactions in some people.

Pine

Pine

5/15

These evergreen trees found all over U.S. make a huge amount of pollen in the spring. That thick yellow layer of powder all over your car is likely from pine trees, but it’s probably not what’s making you sneeze. The heavy waxy coating that makes it easy to see also keeps it from triggering allergies.

Poplar

Poplar

6/15

These trees grow throughout the U.S. and make pollen in the spring. They’re most likely to cause allergy issues in Minnesota and areas in the Southwest, but only the “male” trees make pollen. If you’re allergic to poplar but want to plant one, ask your local nursery for the “female” version.

Walnut

Walnut

7/15

These trees are common in most of the continental U.S. and flower in late spring. Their pollen can be a big trigger for allergies, but it’s heavy and usually drops to the ground before it can travel very far. It probably won’t cause any problems for you unless you live or work right near one.

Ragweed

Ragweed

8/15

This grows everywhere and may be the most common allergy trigger in North America. Its pollen season runs from August to November -- levels are highest around mid-September. It can be worse on hot, dry, windy days.

Bermuda Grass

Bermuda Grass

9/15

The pollen from this kind of grass is a likely culprit for allergy symptoms, and there’s plenty of it around. It’s found in most of the warmer states, often planted on front lawns. It makes pollen when the blades of grass reach about a half-inch high, and it grows for most of the year.

Bluegrass

Bluegrass

10/15

Pollen from the different types of this -- Kentucky bluegrass is a common one -- can cause serious allergies, especially in the summer months when there’s more of it. It’s found in most Northern, Western, and Southern states, but grows best in the cooler regions north of Georgia and west of Texas.

Nettle

Nettle

11/15

This weed found throughout the U.S. makes pollen for most of the year, though more in late summer and fall. It has upright, woody stems that grow 2 to 7 feet tall. You also may have seen “stinging” nettles in the woods. They can stick to you and cause an allergic reaction on your skin, too.

Sagebrush

Sagebrush

12/15

Found all over the Northern, Western, and Midwestern states, these plants make large amounts of pollen (second only to ragweed and grasses) and are very likely to cause allergy symptoms. They can have small yellow or white flowers and grow 1 to 10 feet tall, depending on the type. 

Tumbleweed

Tumbleweed

13/15

Sometimes called pigweed, this is found throughout the U.S. It’s dense with flowers and makes a lot of pollen in late summer and early fall.  If you see the flowers, it’s releasing pollen -- but that’s not the case with all plants.

Lamb's Quarters

Lamb's Quarters

14/15

This plant looks a lot like tumbleweed, but it doesn’t make nearly as much pollen. The two may be confused or possibly grouped together in pollen counts.

English Plantain

English Plantain

15/15

This weed sheds pollen from May to November, and it makes a lot of it. It’s thought to be a major cause of allergies in the Northwest, on the East Coast, and in California.