Harry Barclay says the peppercorn tree on his property loses its leaves when nearby cotton farms spray their plants with defoliant, but the environmental regulator says there is no proof of a link.

Something strange keeps happening to the huge peppercorn tree on Harry Barclay's farm. For at least a decade, he has seen the evergreen shed most of its leaves around March and April.

The peppercorn tree, where it grows, is a visually appealing plant with reddish leaves and clusters of flowers. While often ...

This story appears in the September 2017 issue of National Geographic magazine. The Brazilian pepper tree, an invasive plant in the southern United States, is showing great potential in the fight ...