Dormant seeds in the soil for decades may grow when the conditions are right.
The job of your immune system is to find foreign substances, like viruses and bacteria, and get rid of them.
One trick for remembering the meaning of aggravate is to recall that it rhymes with one of its synonyms, irritate. Younger brothers often aggravate their older brothers, because they find it entertaining to get a reaction out of them.
Aggravate is also used is to mean "make worse." For example, if you have an old knee injury, it's probably best not to climb Mount Everest, because you might aggravate the injury.
Depending on your location, ragweed season may last six to 10 weeks.
Ragweed is a weed that grows throughout the United States, especially in the Eastern and Midwestern states. But that one plant can produce up to 1 billion pollen grains.
If your house is in foreclosure, calling your banker an ugly name is likely only to aggravate the situation.
In the late summer, about 10 to 20 percent of Americans suffer from an allergy to ragweed.
They may do a skin prick test to confirm your allergy.
The pollen then travels through the air to another plant to fertilize the seed so a new plant can grow next year. Near the plants, the pollen counts are highest right after dawn.
The amount of pollen peaks in many urban areas between 10 a.m. Rain and morning temperatures below 50 degrees Fahrenheit slow down the release of pollen. It has been found in the air 400 miles out to sea and 2 miles up in the atmosphere. Turf grasses and other perennial plants easily overgrow ragweed.
When you are allergic to ragweed pollen and inhale it from the air, hay fever symptoms show up. Ragweed also belongs to a larger family of plants that can spread pollen by wind. Members of this plant family include: Some family members spread their pollen by insects instead of by wind. If you have allergies to one type of pollen, you tend to develop allergies to other types of pollen as well.
If you have a ragweed allergy, you may also get symptoms when you eat these foods: If you have severe allergies, ragweed might trigger asthma attacks, chronic sinusitis, headaches and sleep problems.