What weed pollen causes the most fall allergies

What weed pollen causes the most fall allergies

How do scientists know how much pollen is in the air? They set a trap. The trap — generally a glass plate or rod coated with adhesive — is analyzed every few hours, and the number of particles collected is then averaged to reflect the particles that would pass through the area in any 24-hour period. That measurement is converted to pollen per cubic meter. Mold counts work much the same way.

A pollen count is an imprecise measurement, scientists confess, and an arduous one — at the analysis stage, pollen grains are counted one by one under a microscope. It is also highly time-consuming to discern between types of pollen, so they are generally bundled into one variable.

Given the imprecise nature of the measurement, entire daily pollen counts are often reported simply as low, moderate or high.

The American Academy of Allergy, Asthma & Immunology provides up-to-date pollen counts for U.S. states.


The symptoms of allergic rhinitis may at first feel love those of a freezing. But unlike a freezing that may incubate before causing discomfort, symptoms of allergies generally appear almost as soon as a person encounters an allergen, such as pollen or mold.

Symptoms include itchy eyes, ears, nose or throat, sneezing, irritability, nasal congestion and hoarseness.

People may also experience cough, postnasal drip, sinus pressure or headaches, decreased sense of smell, snoring, sleep apnea, fatigue and asthma, Josephson said. [Oral Allergy Syndrome: 6 Ways to Avoid an Itchy, Tingling Mouth]

Many of these symptoms are the immune system’s overreaction as it attempts to protect the vital and sensitive respiratory system from exterior invaders. The antibodies produced by the body hold the foreign invaders out, but also cause the symptoms characteristic of allergic responses.

People can develop hay fever at any age, but most people are diagnosed with the disorder in childhood or early adulthood, according to the Mayo Clinic.

Symptoms typically become less severe as people age.

Often, children may first experience food allergies and eczema, or itchy skin, before developing hay fever, Josephson said. «This then worsens over the years, and patients then develop allergies to indoor allergens love dust and animals, or seasonal rhinitis, love ragweed, grass pollen, molds and tree pollen.»

Hay fever can also lead to other medical conditions. People who are allergic to weeds are more likely to get other allergies and develop asthma as they age, Josephson said.

But those who get immunotherapy, such as allergy shots that assist people’s bodies get used to allergens, are less likely to develop asthma, he said.

How to Avoid Drop Allergies

Avoiding drop allergies is often easier said than done. After every, with work, family, and a social life, you can't shut yourself in with antihistamines and a box of tissues.

Instead, you own to be strategic in how you approach allergy season by taking certain, basic precautions.

Among them:

  1. Vacuum floors, surfaces, and furniture regularly, ideally with a pet-friendly vacuum cleaner designed to suck up dust, dander, mites, and other tiny particles.
  2. Use a HEPA filter and/or air humidifier to hold airborne pollen levels low.
  3. Keep your windows and doors shut at home, especially on days when the pollen count is high.
  4. Check the local pollen and mold counts on the daily weather report.
  5. Wear a NIOSH-rated 95 filter mask when mowing the lawn or doing outdoor work.
  6. Shut the car windows and air vents when driving.
  7. Take a shower and change your clothes after you’ve worked or played outdoors.

Finally, if you own a history of drop allergy symptoms, speak with your doctor or allergist about daily medications you can take to lessen the impact of the season.

Ideally, you should start taking them two weeks before the start of the season to provide you some level of protection.

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  1. American College of Allergy, Asthma, and Immunology.

    "Common Seasonal Allergy Triggers." Arlington Heights, Illinois; updated December 28, 2017.

Itchy eyes, a congested nose, sneezing, wheezing and hives: these are symptoms of an allergic reaction caused when plants release pollen into the air, generally in the spring or drop. Numerous people use hay fever as a colloquial term for these seasonal allergies and the inflammation of the nose and airways.

But hay fever is a misnomer, said Dr. Jordan Josephson, an ear, nose and throat doctor and sinus specialist at Lenox Hill Hospital in New York City.

«It is not an allergy to hay,» Josephson, author of the book «Sinus Relief Now» (Perigee Trade, 2006), told Live Science.

«Rather, it is an allergy to weeds that pollinate.»

Doctors and researchers prefer the phrase allergic rhinitis to describe the condition. More than 50 million people experience some type of allergy each year, according to the Asthma and Allergy Foundation of America. In 2017, 8.1% of adults and 7.7% of children reported own allergic rhinitis symptoms, according to the Centers for Disease Control and Prevention (CDC). Worldwide, between 10 and 30% of people are affected by allergic rhinitis, Josephson said.

In 2019, spring arrived early in some parts of the country and later in others, according to the National Phenology Network (NPN).

What weed pollen causes the most drop allergies

Spring brings blooming plants and, for some, lots of sneezing, itchy, watery eyes and runny noses. According to NPN data, spring reared its head about two weeks early in areas of California, Nevada and numerous of the Southern and Southeastern states. Much of California, for example, is preparing for a brutal allergy season due to the large quantity of winter rain. On the other hand, spring ranged from about one to two weeks tardy in the Northwest, the Midwest and the Mid-Atlantic U.S.

What weed pollen causes the most drop allergies

[Watch a Massive ‘Pollen Cloud’ Explode from Late-Blooming Tree]

Tests & diagnosis

A physician will consider patient history and act out a thorough physical examination if a person reports having hay-fever-like symptoms. If necessary, the physician will do an allergy test. According to the Mayo Clinic, people can get a skin-prick test, in which doctors prick the skin on a person’s arm or upper back with diverse substances to see if any cause an allergic reaction, such as a raised bump called a hive.

[7 Strange Signs You’re Having an Allergic Reaction]

Blood tests for allergies are also available. This test rates the immune system’s response to a specific allergen by measuring the quantity of allergy-causing antibodies in the bloodstream, according to the Mayo Clinic.

Drop Pollen Allergies

Weed pollen is the main cause of hay fever (allergic rhinitis) during the tardy summer and early drop months. Depending on where you live in North America, the main allergen concerns include:

  1. Cocklebur
  2. Burning bush
  3. Sagebrush
  4. Pigweed
  5. Lamb’s-quarters
  6. Ragweed
  7. Russian thistle
  8. Tumbleweed
  9. Mugwort

While the severity of an allergy season can vary by seasonal climate, there can be days (and even times of day) when the allergy risk is high.

This includes windy and warm days when pollen counts can soar. By contrast, rainy days can significantly reduce the pollen count (only to give rise to higher counts when the grasses dry out).

Along with grasses and weeds, mold is a major cause of drop allergies.

What weed pollen causes the most drop allergies

This is especially true in areas where large piles of damp leaves are allowed to sit and rot.

Every About Ragweed

Ragweed is, by far, the leading cause of allergy in the autumn months. The ragweed season can vary but tends to start in August and continue correct through to November in some areas.

Around 75 percent of people with spring allergies will develop a ragweed allergy in drop. The plant thrives in areas where there are cool nights and warm days. While ragweed can beautiful much be found in every part of the U.S.

What weed pollen causes the most drop allergies

(including Hawaii and Alaska), it is most prevalent in the Midwest and on the East Coast where the peak season runs until early- to mid-September.

As with other grass allergies, the pollen is highest during the morning hours, on windy days, and shortly after a rainstorm. Ragweed can grow just about everywhere but can proliferate in fields, along the side of the road, or in vacant lots.

Common allergens

The most common allergen is pollen, a powder released by trees, grasses and weeds that fertilize the seeds of neighboring plants. As plants rely on the wind to do the work for them, the pollination season sees billions of microscopic particles fill the air, and some of them finish up in people’s noses and mouths.

Spring bloomers include ash, birch, cedar, elm and maple trees, plus numerous species of grass.

Weeds pollinate in the tardy summer and drop, with ragweed being the most volatile.

The pollen that sits on brightly colored flowers is rarely responsible for hay fever because it is heavier and falls to the ground rather than becoming airborne. Bees and other insects carry flower pollen from one flower to the next without ever bothering human noses.

Mold allergies are diverse. Mold is a spore that grows on rotting logs, dead leaves and grasses. While dry-weather mold species exist, numerous types of mold thrive in moist, rainy conditions, and release their spores overnight.

What weed pollen causes the most drop allergies

During both the spring and drop allergy seasons, pollen is released mainly in the morning hours and travels best on dry, warm and breezy days.