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10 Worst Plants for Your Allergies


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Pecan
Crack open these pecan shells for a delicious treat.
Crack open these pecan shells for a delicious treat.
iStockphoto.com/Thinkstock

The pecan tree is a type of hickory tree. It's also one of the most allergenic trees out there; it can be as allergenic as ragweed. The tree is native to North America, and is highly prized for both its timber and nuts. In fact, pecan trees in the southern United States produce more than 250 million pounds of pecans in a single year. Oil from pecan nuts is used in everything from processed foods to cosmetics and soaps. Its pollen grains don't travel far but are very large -- therefore, they're also very allergenic.

Pecan tree facts:

  • Appearance: A pecan tree can grow up to 200 feet tall, but when it's cultivated it's typically much smaller. Its leaves are compound -- with leaflets -- and can be up to a foot long. Its nuts are inside husks that split open once they're mature. They're about 1.5 to 2 inches long.
  • Peak time: Spring is the peak time for pecan trees.
  • Location: You'll see lots of pecan trees in Georgia and Texas, as well as the rest of the southeastern United States, and in Indiana and Ohio.

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