Mixed-Species Forests Show Higher Growth and Productivity

New research confirms that canopy complexity in diverse forests leads to 73% higher productivity than in monoculture plots.

Updated on Oct. 28, 2026 in Environmental

A dense, diverse forest canopy viewed from below, showing complex, interlocking tree branches and leaves filtering bright sunlight. — Smithsonian researchers have found that mixed-species temperate forests exhibit 73% higher productivity than monoculture plots due to superior canopy structural complexity. AI Illustration. Upload story photo >

Live Poll

Should local reforestation projects prioritize planting diverse tree species over single-species plots?

Smithsonian researchers have published findings in the journal Ecology showing that mixed-species forests grow significantly faster than single-species counterparts. By analyzing 60 acres of plots, the team demonstrated that biodiversity enhances canopy structure to boost productivity.

Why it matters

Understanding how tree diversity influences carbon absorption is critical for climate mitigation strategies and forest management. This research confirms that ecological complexity directly scales photosynthetic efficiency in temperate forests.

Twelve-species plots showed up to 73% higher productivity and 71% higher canopy complexity compared to single-species plots. The study utilized LiDAR data to measure how varying branch shapes across 17,850 trees enable more efficient light capture.

The players

Smithsonian Environmental Research Center

A research institution focused on environmental science and ecosystem study based in Edgewater, Maryland.

Smithsonian Conservation Biology Institute

A research and conservation facility in Front Royal, Virginia, that serves as a site for long-term ecological experiments.

The details

The researchers employed an experimental design across 70 plots containing 1, 4, or 12 tree species to quantify how forest composition alters growth. By mixing species, the forests developed a more complex canopy structure where different branch architectures allowed trees to interlock, maximizing the total leaf area exposed to sunlight. This structural variation enables the forest to absorb light more efficiently than monoculture plots, where canopy gaps are more common.

2016: A prior global forest study by Liang et al. analyzed 777,126 plots across 44 countries.
2025: Fahey et al. published the productivity findings in the journal Ecology.

The Tech Race

This research builds upon global forest productivity trends identified in 2016 to provide granular, site-specific mechanisms for why diversity matters. It bridges the gap between large-scale forest modeling and controlled, species-specific physiological experiments.

These findings provide a blueprint for land managers and conservationists to optimize reforestation efforts for higher carbon sequestration rates. While the immediate results are confined to experimental sites, the data offers a clear rationale for favoring diverse plantings in future restoration projects.

The takeaway

Biodiverse forests utilize light more effectively than monocultures, offering a clear strategy for maximizing carbon sequestration in future climate efforts. Readers should monitor upcoming follow-up studies as researchers continue to track these specific plots through the forest maturity cycle.