Fall Allergies

Fall Allergies can be a troublesome time for many. We have endured the tree allergy season. It came on strong and lasted for a short period of time. The grass allergy season followed and lasted all summer long. Weed allergy season is the third and final phase of the pollen allergy season.

Fall allergies troubles so many people because ragweed is the leading producer of pollen production.

There are many types of weeds and molds that cause fall allergies. But because RAGWEED is the main offender, this article takes a look at how ragweed gets ready for the fall allergy season. It also takes a look at mold as being the second offender.

1. The Ragweed Plant Emerges

Ragweed is growing all around us from spring to fall. It likes to grow out in fields and where new construction disturbs the soil. It likes to grow in fields and around railroad tracks. Below shows pictures of ragweed growing uncheck. It is hardly noticeable as the pollen is not yet ready to affect people. Most people see the weeds but don't even know that it is ragweed that is growing.

2. The Plant Continues to Grow all Season

Short ragweed can grow 1-4 feet tall. Tall ragweed can grow 10 to 12 to 15 feet tall. It is a very hardy weed and well equipped to compete with other vegetation. In the pictures below, the corn is about 6-8 feet tall and getting close to harvest time.

3. Pollen Production Begins

At the end of summer, ragweed begins producing pollen for reproduction and its survival...something it does well. It produces "spikes" at the top of the plant. This is what becomes the pollen and will eventually get released into the wind.

4. The Pollen on the Plant Starts to Mature

As the pollen grows, the color is green. As the pollen starts to mature, it goes from green to yellow. The yellow pollen is dryer getting ready for the wind to take it. The dryness will let the wind carry it further away.

5. The Pollen is Starting to be Released

The picture below shows the spikes at the top of the plant. Notice how the wind has started to take it. You can see some of the "clusters" still there and some of the spikes that has already released the pollen.

Ragweed produces pollen in large numbers. The pollen is very small, light weight and very aerodynamic. It stays airborne for a very long time. For those of us allergic to it, we are bound to enter into its path and develop ragweed symptoms.

MOLD

Mold is the other prominent source for fall allergies. It is one of the most widespread living organisms. There are thousands and thousand of different types of mold and they are found everywhere...including the Antarctica. They are a source of indoor allergies and they are the source for outdoor allergies. Every season is the season for them to produce their allergens. Although they are classified as perennial allergic rhinitis, their numbers may be highest during fall months.

They do not have chlorophyll so they do not need the sun to survive. Instead, they derive their energy by living on other organic matter that they decompose for their nourishment.

Mold can grow practically anywhere. They are not fussy about their living conditions. Any place that is damp and dark and will be an ideal spot for their spores to take root and colonize. They do not need much ventilation either. This is why our homes is an ideal spot for them to grow. This is also why they can be a problem all year long.

Fall is an ideal time for mold to grow and to cause fall allergies. As the temperature stays cooler, the moisture in our environment stays longer and does not evaporate so fast. The lingering moisture presents the ideal growing conditions for mold.

The picture on the left shows the tree during the summer months when the temperature is warmer and dryer. You can hardly see the mold. It's there, but it is more in a dormant state.
The picture on the right shows the same tree when the temperature is cooler and there is moisture in the air. There is not the hot sun to dry up the moisture.

Clearly, the change of seasons provides the mold with moisture which is one of the primary requirements for mold growth. As the dampness wakes up the mold from dormancy, the mold sends their spores into the air causing fall allergies.

The picture above shows a close up look at the mold on the tree. It is not hard to believe that this thriving colony will sends it's spores into the air as the temperature and moisture is right for growth. People allergic to mold will notice it more outside during fall. (Of course, they notice it year-round if their indoor environment has a mold problem.

During fall, mold likes to grow on rotting wood, fallen leaves, compost piles, trees, hay fields, firewood, fences, gutters, siding and anywhere that there is the slightest bit of dampness...including your bathroom. The places that I inspect first is usually on the north side of the building because that is where the most shade is. Even in the pictures above, the mold is growing on the north side of the tree.

The cold winter does not kill the mold either. It goes dormant but it does not die. It can even survive subfreezing temperatures. But come spring when the snow is thawing and more moisture is in the air, the mold will come out of its dormancy and send it's spores into the air once again.

These spores are extremely small in size. They can range from 5 to 15 microns in diameter. This presents a very special problem for those with asthma. This small size penetrates deeper into our respiratory system. Many people with asthma are sensitive to mold spores.

This small size also makes them smaller than most pollen. The smaller the particles size, the longer they will stay airborne. This, along with the sheer number of spores released makes them a formidable problem for fall allergies.

Return to the ragweed allergy article.

Go to the nasal allergy HOME PAGE from fall allergies.

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