Tropical mixed-species plantations can be better than monocultures for storing carbon and making money. A study in Costa Rica compared them and found that mixed-species stands can earn more money and store more carbon than monocultures. The best mixed-species stand had a 7% higher carbon storage than the best monoculture. This means that planting different tree species together can be a good choice for forest investors, especially when the best tree species for a site is not known or when using less common tree species.