In 2003, China planted small islands of native trees along a degraded river; 20 years later they held only 19–30% of an intact forest’s diversity and biomass

• Tropical forests have been heavily degraded because of human activities.
• (Representational photo)Planting trees across vast areas may not be the only way to restore damaged tropical forests, according to a new study.
• Instead, small patches of native trees can gradually help degraded forests recover.