Fall is the time when most Texans are looking forward to cooler temperatures and spending more time outside. Unfortunately, ragweed allergies can keep some people from enjoying the nicer weather. Ragweed is one of the most prevalent allergens in North America, coming in second only to mold. In this blog, we'll go over the basics of ragweed, including where you can find it, why it's so allergenic, its benefits, why it may be causing your mouth to itch and ways to reduce ragweed allergies naturally.
Table of contents
What is ragweed?
Ragweed is a family of flowering herbs and shrubs in the Ambrosia genus. The name comes from the Old English "raf geweede" meaning ragged weed, due to the shape of the leaves. There are over 40 species of ragweed, with 17 widely-distributed species in North America.
Due to its ability to grow in all types of areas, including industrial, urban and roadsides, it has become invasive. Ragweed pollen is one of the most common allergens, causing about half of all cases in North America.
"Ragweed pollen is arguably the largest single seasonal allergen in North America."
Where is ragweed found?
Ragweed is native to North America, originating from the southwestern US and northwestern Mexico. It's found in tropical to subtropical and temperate areas.
Ragweed spread to Europe in the 1800s through imported seeds and horse feed. Recently, it has spread throughout the continent, due to the seeds being included in imported bird feed. It is now considered an invasive alien species, spreading as far North as Denmark.
What types of ragweed are found in Texas?
There are 9 varieties of ragweed in Texas:
- Common/Common/Short Ragweed (Ambrosia artemisiifolia)
- Giant/Great Ragweed (Ambrosia trifida)
- Rio Grande Ragweed (Ambrosia cheiranthlfolia)
- Flat-Spine Burr-Ragweed (Ambrosia acanthicarpa)
- Western/Perennial Ragweed (Ambrosia psilostachya)
- Lance-Leaf Ragweed (Ambrosia bidentata)
- Skeleton-Leaf Burr-Ragweed (Ambrosia tomentosa)
- Weak-Leaf Burr-Ragweed (Ambrosia confertiflora)
- Woolly-Leaf Burr-Ragweed (Ambrosia grayi)
What does ragweed look like?
The most common varieties of ragweed are Common Ragweed and Giant Ragweed. Their flowers have a similar appearance, but their leaf shape and height vary greatly.
Does ragweed have any benefits?
Despite its negative connotations as invasive and allergenic, ragweed does provide some benefits.
Giant ragweed, common ragweed and western ragweed were used medicinally by a variety of Native American tribes as a remedy for issues such as nausea, menstrual pain. insect stings, fever, and pneumonia. Birds love to eat the seeds due to the high oil content.
Ragweed plays a role ecologically in supporting insects and pollinators. Giant ragweed and western ragweed are used by bees as a source of food. Common ragweed is a host plant for caterpillars, beetles and grasshoppers.
Ragweed is also being used to combat soil pollution. Common ragweed is used to remove heavy metals such as lead from polluted soil, absorbing the metals in the soil into their roots.
"Almost 50 million people in the U.S. have symptoms from an allergy to ragweed pollen."
How common is ragweed allergy?
Ragweed is one of the most prevalent allergens, "second only to mold in causing allergic symptoms." Because ragweed can be found in every US state except Alaska, ragweed allergies are extremely common.
Although ragweed plants only live for 1 year, ragweed seeds can stay dormant for up to 30 years, with each plant producing "up to 62,000 seeds." It grows well in poor soils and a wide range of environmental conditions.
Due to rising temperatures and higher carbon dioxide levels, ragweed pollen season is becoming longer, causing more severe symptoms and affecting quality of life for those suffering.
People living in urban areas are especially vulnerable, due to the "Urban Heat Island" effect. Urban areas are more likely to have higher pollen counts due to warmer temperatures and higher levels of carbon dioxide. A study from China in 2025, looked at the prevalence of respiratory allergy symptoms in preschool children exposed to urban heat island effects. They found an increased risk of wheezing, cough and rhinitis in children exposed to more heat.
What are the symptoms of ragweed allergy?
- Runny and stuffy nose
- Sneezing
- Watery or itchy eyes
- Scratchy throat or itchy ears
- Cough and postnasal drip
- Wheezing and difficulty breathing
- Fatigue and trouble sleeping
- Headaches and sinus pressure
- Hives and contact dermatitis
- Eczema
Why is ragweed so allergenic?
Ragweed pollen is extremely pervasive due to the fact that a single plant "may produce about a billion grains of pollen per season." Due to its light weight, pollen grains are able to travel hundreds of miles.
Ragweed's allergenicity increases when it grows alongside polluted traffic roads. Ragweed pollen content has been shown to increase with rising carbon dioxide concentrations.
When is ragweed highest?
Ragweed season generally starts in late summer, around August and lasts until the first freeze of the year, peaking in mid to late-September. Due to rising temperatures and increased pollution, allergy seasons are starting earlier and lasting longer. Some southern states may start to experience ragweed pollen as early as July.
Pollen counts are at their highest in the mornings, and are worse on warm, humid and windy days.
Does ragweed cause oral allergy syndrome?
Ragweed is one of the most common causes of Oral Allergy Syndrome (OAS), also known as Pollen Food Allergy Syndrome (PFAS). OAS is caused by an immune response due to a similarity in the proteins of certain foods to pollen. OAS can occur with a variety of trees, weeds and grasses.
If you experience itching or swelling around your mouth when eating certain foods, such as melons, bananas, lettuce and even chamomile tea, you may be experiencing OAS due to ragweed. You don't have to avoid your favorite foods altogether - cooking, peeling or canning these foods can help to prevent symptoms.
Three ways to naturally reduce ragweed allergies
Despite the increase in ragweed allergies, there are natural ways to help control symptoms. Consult your healthcare professional before starting any new supplement.
Stinging nettle
Stinging nettle is a flowering plant native to Europe, that has been used for traditional medicine, food, tea and textiles.
Studies have shown that nettle extract (Urtica dioica) can help to prevent immune inflammatory responses that cause allergic symptoms. It's recommended to take stinging nettle before ragweed season starts to prevent symptoms.
Quercetin
Quercetin is a flavonoid found in onions, apples and red grapes, that's well known for it's antioxidant properties. Quercetin has been studied for its effect on suppressing allergic reactions and inflammation.
Quercetin is also known for its effects on enlarged prostate, blood sugar and insulin, blood pressure and rheumatoid arthritis.
Quercetin may be better absorbed from food than supplements. If adding quercetin-rich foods to your diet, choosing organic may provide more flavonoids.
Seasonal Allergy Formula
Our Seasonal Allergy Formula is a homeopathic blend specifically formulated for a variety of allergens, such as:
- Weeds including Ragweed
- Trees including Oak and Elm
- Dust
Seasonal Allergy Formula is tasteless, dairy, gluten and alcohol-free and safe to use with pets. We recommend taking 6-10 drops every 4 hours while experiencing allergies.
Conclusion
Ragweed can be a difficult allergen to deal with, due to its prevalence, invasiveness, long allergy season and high pollen counts. Despite these negatives, there are several ways to naturally deal with ragweed allergies. Don't forget that there are also ways to help prevent allergy symptoms before they appear.
Elizabeth Reedy, LAc
Elizabeth is a licensed Acupuncturist and Chinese Herbalist. She has been working in the holistic health field for over 20 years. She enjoys researching and writing about health issues, as well as exploring integrative therapies and natural products.