How can you hear the beautiful spring birdsong when you’re too busy blowing your nose? Allergies affect between 10% and 30% of American adults, and more than 400 million people globally. But what are the culprits?
Trees release their pollen in the air, which blows around your yard, onto your house, and into your body, leading to annoying tree allergies. To avoid planting kryptonite in your yard, we’ve compiled a list of some of the worst trees in the U.S. for allergy sufferers.
Just because you see a tree on this list doesn’t mean you need to avoid it forever. Trees are either monoecious or dioecious:
- Monoecious trees produce flowers that are both male and female, so each tree can self-pollinate.
- Dioecious trees produce flowers that are either male or female, and the male tree pollinates the female tree.
Male dioecious trees produce pollen, while female dioecious trees produce fruits and/or seeds. Monoecious trees produce both. So, if you want to avoid trees with a lot of pollen, avoid planting male dioecious trees and pollen-heavy monoecious trees.
If you love mulberry trees, or other dioecious species that are known to cause allergies, opt for female or sterile trees at the nursery. Just don’t expect any delicious mulberry fruits if you only plant female trees, since they need pollen from male trees in order to reproduce.
- 1. Birch trees
- 2. Beech trees
- 3. Cedar trees
- 4. Cottonwood trees
- 5. Elm trees
- 6. Hickory trees
- 7. Maple trees
- 8. Mulberry trees
- 9. Oak trees
- 10. Pine trees
- What is tree pollen?
- Signs you may have tree allergies
- How to manage tree allergies
- FAQ about the worst trees for allergy sufferers
1. Birch trees
Birch trees are deciduous trees distinguished by their tall trunks and papery bark, which ranges in color from white to gray and light yellow. Their leaves are double-toothed, with an egg shape and pointed tips.
Birches trigger a range of symptoms, from sneezing and congestion to oral allergy syndrome (OAS). If your mouth or nose starts to tingle, or you get hives after touching certain raw fruits and vegetables (like apples or almonds), you may have a birch allergy and your body is cross-reacting.
Birch trees are commonly found in meadows, grassy areas, and forests across the United States, especially in the eastern third of the country. Not only are birch trees pollen-producers, but they also have short lifespans compared to other hardwoods and are vulnerable to pests and disease.
Birch trees are monoecious and bloom in the spring, typically between late May and early June.
Common species of birch to look out for include:
- River birch (AKA black birch) is a popular choice for landscaping, especially in eastern regions with moist soil and water sources. It can grow in planting zones 4 to 9.
- Paper birch (AKA silver birch, white birch, or canoe birch), is commonly found in northern and central forested regions, in zones 2 through 7.
- Sweet birch (AKA cherry birch), grows throughout the eastern U.S., with high concentrations in and around Appalachia. It grows in zones 3 to 7.
- Yellow birch (AKA swamp birch), is seen in swampy or marshland areas in the Northeast within zones 3 to 7.
2. Beech trees
Tall beech trees are popular for ornamental landscaping and adding a bit of extra shade to your yard. They have glossy leaves and dense foliage, which is why many choose to plant them as cooling shade trees. Beech trees are monoecious and produce a lot of pollen.
Beech trees flower between March and May. They’re commonly found across the eastern half of the country and can live for hundreds of years.
- European beech is native to Europe, but grows in USDA zones 4 to 7.
- American beech occurs in USDA zones 3 to 9.
3. Cedar trees
There are two kinds of cedars: “true” ornamental cedars (Cedrus) that are native to the Himalayan and Mediterranean regions, and cedars you’ll find across North America, which have the genera Juniperus, Chamaecyparis, and Thuja. These evergreen cedars have small leaves that grow in flattened branches and can be prickly to the touch.
Cedar fever is a big problem in central Texas due to the high concentration of mountain cedar trees. Runny noses, fatigue, sneezing, and low fevers are common symptoms in the late winter and early spring.
Western red cedar asthma is the primary culprit behind occupational asthma in the Pacific Northwest.
These cedar trees can be monoecious or dioecious.
The worst cedars for allergy sufferers are:
- Mountain cedar (AKA Ashe juniper), grows in the central U.S., mostly in the Texas Hill Country region, Ozarks, and mountains in Oklahoma. It grows in zones 7 through 9.
- Eastern red cedar (AKA Virginia juniper), is native to and mostly found throughout the eastern half of the United States, thriving in USDA zones 2 through 9.
- Western red cedar (AKA Rocky Mountain juniper), is found throughout the Pacific Northwest in regions with hardiness zones 5 to 9.
4. Cottonwood trees
Cottonwoods are America’s fastest-growing trees, typically grown as shade trees. They have triangular “toothed” leaves and drop cottony seed pods in the spring. Many neighborhood associations have bans against planting cottonwood trees since their distinctive cotton pods can easily clog filters.
Cottonwoods naturally grow along rivers and streams and flower from April to May, which is around the time when your cottonwood allergies might flare up.
Common types of cottonwoods in the U.S. include:
- Eastern cottonwood grows in eastern states, thriving in hardiness zones 2 through 9.
- Black cottonwood is found west of the Rockies, from Alaska to California in zones 4 to 8.
- Fremont cottonwood (AKA western cottonwood) can live in USDA zones 3 to 9, and grows naturally throughout the Southwest.
5. Elm trees
Previously devastated by Dutch Elm Disease, elm trees are now making a comeback. These monoecious shade trees are commonly grown in the Midwest and the eastern United States. These semi-deciduous trees typically have gray-colored bark and oval-shaped, green leaves.
Most elm trees release pollen between February and late March, though cedar elms pollinate between August and October.
- American elm is the state tree of North Dakota and Massachusetts, and can be found in the eastern U.S. between zones 2 and 9.
- Cedar elm is commonly found in Texas and other southern regions, in growing zones 6 through 9.
- Chinese elms are immune to Dutch Elm Disease, and grow in hardiness zones 5 to 9.
6. Hickory trees
There are two kinds of hickory trees: Pecan hickory, and true hickory. True hickory trees cause moderate allergies, while pecan hickory trees typically lead to more severe immune responses.
Most hickory trees are tall, some reaching 100 feet or higher, and have scaly, gray bark. They are most often found in the Southeast and Midwest but can grow across the Southwest and Northeast, as well.
Hickory and pecan trees are monoecious and typically pollinate in late spring, between April to June.
- Pecan trees are massive and popular in the Southeast, thriving in hardiness zones 6 to 9.
- Shellbark is widely distributed, especially in the Midwest. This tree grows in zones 4 through 8.
- Shagbark has distinctive peeling bark, and grows in zones 4 to 8 throughout the Midwest and Northeast.
7. Maple trees
Most maple trees have characteristic leaves with a palmate (handprint-like) shape, as seen on the Canadian flag. They can reach 50 to 150 feet tall and are popular for maple syrup production and ornamental uses thanks to their stunning fall foliage.
Maples pollinate in the spring, so many people experience allergies between March and April.
While there are some region-specific maples, including canyon maple, Florida maple, and black maple, the most common maple trees in America are:
- Sugar maples are common in the eastern U.S., with fall foliage ranging from yellow to orange and red (sometimes at once). They grow in USDA zones 3 through 8.
- Red maple can be considered invasive in regions with native oaks and is the most widespread maple in eastern regions. It can thrive in zones 3 to 9.
- Silver maple is a fast-growing variety grown for shade in eastern regions. It can grow in hardiness zones 3 to 9.
- Boxelder is the most common maple tree in the Midwest, with a different leaf shape than other maples — it has pinnately compound leaves (pairs of leaflets on either side of the stem). It grows across the country in zones 2 to 9.
- Bigleaf is the largest of American maples, found along the Pacific coast. It can grow in plant hardiness zones 5 to 9.
8. Mulberry trees
Mulberry trees are medium to large-sized, with dark green leaves that have serrated edges. They produce tasty mulberry fruit in the summer and are easy to care for, which is why they’ve become such a popular landscaping tree.
Red mulberry is native to eastern states, and white mulberry (native to China) is spread across the country.
Mulberry trees don’t have a long lifespan, but they can spread rapidly. Some cities — like El Paso, Texas; Tucson, Arizona; Las Vegas, Nevada; Albuquerque, New Mexico; and Phoenix, Arizona — have banned residents from planting mulberry trees due to pollen problems.
Mulberry trees tend to pollinate between February and April. Mulberries are deciduous trees, so avoid male mulberries if you have allergies. Just know that without a male tree to fertilize the female trees, you won’t get berries in summer.
- White mulberry, the most popular mulberry in North America, can be found in every continental state. It is hardy in zones 3 through 9.
- Red mulberry grows naturally in the eastern U.S., in hardiness zones 3 through 8.
- Texas mulberry appears more like a shrub and is scattered across the Southwest, growing in Arizona, Oklahoma, New Mexico, and Texas (USDA zones 5 to 9).
9. Oak trees
Mighty monoecious oak trees have historically dominated the eastern U.S., growing in forests and along coastal plains. There are many kinds of oak trees, each with different visual characteristics, but all produce acorns. Many oaks are grown as tall shade trees, and they can live for hundreds of years.
The pollination period for oak trees begins in early spring, typically between late March and early April, with allergy symptoms subsiding around early May. In 2021, oak tree allergies had a record season in San Antonio, producing the highest pollen count in the region in 26 years.
Many oak varieties are limited to specific regions, like stone mountain oak near Atlanta and blue oak in California. Some of the most common varieties include:
- White oak grows along the eastern U.S. in USDA zones 3 through 9.
- Northern red oak thrives in plant hardiness zones 3 to 8 in eastern states north of Georgia.
- Live oak is often found draped in moss across the South, it grows in zones 8 through 10.
10. Pine trees
Pine trees produce a lot of pollen which can travel far distances, from dozens of miles up to 1,800 miles. These coniferous, evergreen trees produce long needles and drop sticky pine cones in the fall.
Not to be confused with Christmas tree syndrome, pine pollen allergies affect most people during the spring, with pollen levels peaking in April. Pine trees can be either monoecious or dioecious, but most are the former.
Common pine trees in America are:
- Eastern white pine trees grow in the eastern half of the U.S., in zones 3 through 8.
- Sugar pine is most commonly found along the West Coast in hardiness zones 7 to 9.
- Pitch pine is a Northeast and Mid-Atlantic tree, thriving in zones 4 through 7.
- Longleaf pine is popular in the South, especially along coastal plains in USDA zones 7b to 9b.
What is tree pollen?
Pollen is a yellow or yellowy-green powder that is created by male reproductive systems in plants. During the pollination season, male trees (or male parts of monecious trees) produce pollen grains that contain their sperm cells. Once the pollen comes into contact with a female tree’s reproductive system, the tree is pollinated.
Tree pollen can be transported by bugs and birds, but it is most often dispersed by the wind, which can carry pollen pretty far, from dozens to hundreds, and sometimes even thousands, of miles. Trees and other plants often pollinate during the spring, which is commonly referred to as pollen season or spring allergies.
How does pollen cause allergies?
People suffer from an allergic reaction when their immune systems respond to the large amounts of pollen in the air. This immune response is characterized by typical allergy symptoms (red eyes, itchy eyes, stuffy nose, etc.) as your body tries to fight off the “invading” pollen.
There are different types of pollen, so your allergies may flare up in different environments or at different times of the year based on the kinds of pollen you encounter.
What does climate change have to do with my allergies?
You may have noticed that your allergies have been getting worse in the past few years, with symptoms occurring for longer periods. Unfortunately, climate change is playing a big part in the severity of your allergies.
With the planet warming, planting and pollination seasons are changing. Warmer temperatures lead to extended periods of pollination and more pollen for you to breathe.
Signs you may have tree allergies
Allergies can strike at any time of the year, depending on where you live and what trees are blooming in your area. If you have seasonal allergies, you probably experience symptoms at about the same time each year.
Most trees pollinate in the spring, triggering allergies (AKA “hay fever”) between March and May. In warmer climates, allergies can flare up in the fall between September and December. Some trees, like cedar, pollinate in the winter and can cause flare-ups as early as December.
Typical allergy symptoms include:
- Watery eyes
- Itchy eyes, nose, ears, and mouth
- Nasal congestion and mucus
- Runny nose
- Sore throat
- Plugged ears
- Red, swollen eyes
- Runny nose AKA rhinorrhea
- Sinus infection
People with allergic asthma also may experience asthma symptoms during allergy season.
If you’re not sure whether you’re experiencing allergies or another problem, examine your mucus (we know, it isn’t the most pleasant task): allergy mucus is typically clear and runny, while cold mucus is discolored and thick.
Allergy flare-ups also can be caused by ragweed pollen, grass pollen, pigweed pollen, and flower pollen.
How to manage tree allergies
Tree pollen is minuscule and can travel for miles. But making your yard allergy-free can help mitigate the problem. A tree in your yard will expose you to much more pollen than one that’s at your neighbor’s house down the road.
You can relieve many symptoms by using:
- Nose spray (Cromolyn sodium)
- Nasal corticosteroids
- Leukotriene receptors
- Neti pots, or other nasal irrigation devices
- Over-the-counter allergy medications
It’s recommended to begin taking allergy medications ahead of time, especially if you suffer severely from tree allergies. If your symptoms are severe, it can be beneficial to get allergy testing from an immunologist. This can help you discover your allergy triggers so you can plan to avoid them.
After consulting with an allergy specialist, your doctor might recommend over-the-counter medications or allergy injections.
Other ways to manage pollen exposure include:
- Keeping doors and windows shut
- Avoid going outdoors in the morning (between 5 a.m. and 10 a.m.), as this is typically when pollen counts are the highest
- Wash pollen off of your car
- Wear a hat and face mask when going outside
- Change your clothes and shower or wash your face after going outdoors
- Avoid wearing contact lenses, which pollen can stick to
- Wear long sleeves, sunglasses, pants, a hat, and gloves while doing yard work
- Plant female trees
- Plant sterile trees
FAQ about the worst trees for allergy sufferers
Your city’s urban planning might have something to do with your allergies. Sometimes city planners prefer planting male trees since they don’t drop “tree litter” like fruit or seeds on the sidewalk. The downside to tidy male trees? They produce pollen, making the outdoors insufferable for those with allergies.
Some types of trees are hypoallergenic, and others have pollen that is bigger or stickier, and therefore less likely to fly into your respiratory system.
While the male dioecious trees and pollen-heavy monecious trees listed above can be a huge problem for allergy sufferers, some nurseries sell female dioecious trees that might produce “tree litter” like seeds, but not pollen. Nurseries also may sell sterile male trees.
Some female dioecious trees that do not produce pollen include:
These trees can be messy in the spring but are better to plant if you want to avoid dealing with a sore throat and watery eyes.
Some monoecious trees, like oaks, can be terrible during allergy season. Other monoecious trees carry pollen that’s less allergenic or is so heavy that it won’t drift into your sinuses. Many of these trees produce fruit or large flowers in the spring.
Low-pollen monoecious trees include:
The weather plays a big role in how much you’ll suffer from allergies. Windy days cause pollen to be more abundant in the air. Rainy days wash pollen off of trees and out of the air, so it’s safer for those with allergies to venture outdoors after a rainstorm.
Want a beautiful lawn without exposing yourself to allergenic pollen? Contact a local Lawn Love pro to tackle your yard to-dos with ease.
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