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How Do Tumbleweeds Spread Seeds Across Dry Land?
风滚草如何在干旱土地上传播种子？
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Tumbleweeds are whole plants that break free from their roots when dry and roll with the wind.
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Their round, spiny shape helps them bounce over rough terrain without getting stuck easily.
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As they tumble, thousands of tiny seeds shake loose from special compartments inside the dried branches.
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These seeds have tough outer coats that let them survive long journeys across deserts and plains.
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Wind speed, terrain slope, and rainfall patterns all influence how far a tumbleweed travels before stopping.
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Once it lands in moist soil, the plant’s remaining seeds may germinate when spring rains arrive.
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Some tumbleweeds spread invasive species, while others help native grasslands recover after fire.
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Unlike most plants, tumbleweeds don’t rely on animals or water—they use pure physics to disperse life.
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Botanists study their movement to improve models of seed dispersal in arid ecosystems.
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This clever survival strategy shows how evolution shapes motion into a tool for reproduction.