Once Upon a Chestnut: A Main Idea Teaching Text for Students

   

 It's important to help readers see that multi-paragraph texts are nested combinations of main ideas. Paragraphs have main ideas which build up to section main ideas which build up to article main ideas. 

     I wrote the text below as an example of this. After the introduction, each section has a clear, easy-to-find main idea. Not only was this a good text to use to teach science concepts, but it was able to serve double duty as an ELA text too.

     To find a formatted version of this text with ready-to-use activities, click here: Main Ideas and Details in Expository Text.

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Once Upon a Chestnut

    It was called the perfect tree. It grew tall and fast. Its nuts could feed people, wildlife, and livestock. Its wood could be used for fences and railings. Its large leaves shaded forests up and down the East Coast.
But now, it is almost impossible to see. This tree was the American chestnut tree. One hundred twenty years ago, the American chestnut tree was common in North America. But virtually none can be seen today. What happened?

Exciting Times, Exchanging Trees 

    The 1800s were an exciting century for gardeners. Schooners and steamships made oceanic travel faster and easier, and shipping goods became less expensive. People enjoyed learning about new kinds of plants. They sent different specimens from place to place. The beautiful magnolia tree, a native of Central and North America, was grown in European gardens. Gardeners brought many beautiful plants from China and Japan to America. 

A Deadly Blight 

    One of these exotic plants was the Japanese chestnut. The Japanese chestnut was brought to the United States as a crop tree. People hoped to be able to sell the harvest from the Japanese chestnut tree. They also liked the looks of the Japanese chestnut. They described it as more ornamental than the tall, fast-growing American chestnut. 

    What people didn’t realize is that these trees were bringing an unexpected problem. A fungus that caused a blight, or tree disease, had come along with the trees. This fungus didn’t cause much harm to the Chinese and Japanese trees. But the American chestnut trees had no resistance. Once they were infected, these trees died. 

A Problem That Couldn’t be Solved 

    The study of forestry, or tree management, was just beginning in the United States. Many states quickly had scientists set to work studying the blight. These scientists tried to figure out what to do to stop the spread of the fungus. Some scientists recommended cutting a few trees to look for the blight. Others thought that the blight would kill trees for only a few years, and then the remaining trees would be able to bounce back. 

    But the problem couldn’t be solved. Within fifty years, the American chestnut had disappeared almost completely. Scientists estimate that almost four billion trees died. In some places, the roots of the chestnut tree send up new shoots. These can grow for up to fifteen years before they, too, die of the blight. 

    The largest grove of mature chestnuts still standing can be found in Wisconsin. However, even these chestnuts seem to be having trouble. Will they last another hundred years? Or will they disappear like the other American chestnuts? 

Looking to the Future
    The American Chestnut Foundation is a group that is still working to bring back this once common tree. Through scientific research and genetic mixing, they are trying to save the American chestnut. They have planted thousands of trees in the last ten years. Some of these trees were planted on bare mountainsides that had been destroyed by coal mining. If the chestnut trees survive, what was once a muddy wasteland could become the American chestnut forest once again.