Self-Fertilizing Tree Branches Out

A tree from China that fertilizes itself could help lower the cost of landscaping in the United States, Agriculture Department scientists say.

Bacteria in the roots of the tree, which is named Mackia amurensis, allow it to convert nitrogen from the air into a form it can use for growth. Thus, anyone who plants the tree will not have to use nitrogen fertilizer, said Peter B. van Berkum, a USDA plant microbiologist in Beltsville, Md.

Not only would that lower costs, it also would reduce the chance that fertilizer, as it changes to nitrate in the soil, would pollute water sources, Van Berkum said.