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In this unlikely place, researchers are putting the seeds from flowering plants and trees in a sleeplike state. Many years from now, other workers will wake the sleeping seeds up to plant them they are most needed. These seeds arethe legendary Rip Van Winkle, who fell asleep under a tree and woke up 20 years later.
The small farm, called the Greenbelt Native Plant Center, is part of a global effort to save(threaten) plants and trees. Around the world, native plants are being crowded out by invasion newcomers. Native plants have less room to grow nowa result of the growth and spread of cities. And global warming is making some places hotter, drier, or different fromnative plants are used to.
Experts used to thinkpossible to protect big-city plants such as American bittersweet because growth space is limited in urban environments. Crowding increases competition between natives and invaders, and the latter often win the battle.
, scientists have found waysfighting back. So far, workers at the Greenbelt Native Plant center(gather) seeds from about 300 of those plants and put them in a sleeplike state. When(plant) in the future ,these seeds could help restore damaged parkland and forests.