Hybrid 'Grassy Tree' Plants Offer Carbon Storage Benefits and Community Sustenance

Bamboo, palm, and banana trees have been newly defined as 'grassy trees', a group that blends the strength of trees with the speed and resilience of grasses. This new categorization provides a standardized framework for studying these species, leading to new opportunities for carbon storage, ecosystem recovery, and sustainable living. 

Though they resemble trees, bamboo, palm, and banana trees are biologically closer to grasses, as their stems do not widen with age. Their towering structure, however, has made classification and understanding of their biology challenging.

A new study by scientists at New York University provides clarity, describing these species as "grassy trees". The findings were published in Trends in Ecology and Evolution.

Combining the canopy form of trees with the resilience of grasses, grassy trees are well equipped to withstand and recover from extreme weather conditions.

Bamboo, palms, and bananas, which don’t fit neatly as ‘trees’ or ‘grasses,’ are actually a powerful group of plants we call ‘grassy trees’ that combine the best of both worlds. Their hybrid nature - combining the tall structures of trees with the rapid growth of grasses - makes grassy trees powerful allies in responding to climate change.

Aiyu Zheng, Researcher and Study Lead Author, Department of Environmental Studies, New York University

Zheng suggests that these species can quickly recover after fires and storms, help restore landscapes, store carbon, sustain communities, and support biodiversity. The benefits of such species, she contends, are varied, stretching from food to renewable materials and green energy. 

Our study provides the first global overview of how much carbon grassy trees capture and store, showing that they are abundant, practical, and deeply embedded in tropical cultures - and thus deserve to be at the same table as other better-known nature-based solutions.

Mingzhen Lu, Study Senior Author and Assistant Professor, Department of Environmental Studies, New York University

The study authors emphasize that this new and more accurate identification is essential. This standardized framework will allow researchers to chart the distribution of grassy trees more effectively and measure their contributions, from carbon storage and biodiversity improvements to economic advantages.

For example, bamboo can be used to produce biodegradable plastic, aiding in reducing global plastic waste. Such insights could also help governments and communities to plan and invest in sustainable development projects more effectively.

Because these species are widely cultivated and locally familiar across much of the tropics - such as village groves, natural forests, and commercial plots - this research turns ‘grassy trees’ into a practical playbook: pick the right species, support locals’ successful planting and management efforts, and track outcomes - the carbon they capture, the income they generate, and the depth of their resilience.

Aiyu Zheng, Researcher and Study Lead Author, Department of Environmental Studies, New York University

To conduct their analysis, the researchers gathered datasets concerning 12 types of ecosystems primarily characterized by trees, grasses, or grassy trees. They compared above- and below-ground carbon stocks and measured productivity, which refers to the rate at which plants absorb carbon dioxide for growth.

The 12 ecosystem types include:

• Tropical, temperate, and boreal forests (dominated by trees)
• Savannas, grasslands, and croplands (dominated by grasses)
• Bamboo forests and plantations of palms and bananas (grassy-tree systems)

The study indicated that ecosystems dominated by bamboo, palms, and bananas, often excluded from existing classifications, differed significantly from other tree- and grass-dominated ecosystems.

These grassy-tree ecosystems generally exhibited greater productivity than tree- or grass-dominated systems, but held an intermediate capacity for carbon storage: lower than trees but higher than that of grasses.

The authors additionally highlighted three successful instances of employing various grassy tree species tailored to the needs of local communities and development priorities, illustrating the adaptability of grassy trees as effective climate solutions:

• The moriche palm in South America supports wetland biodiversity and conservation while providing communities with nutritious fruits and oil.
• Lowland bamboo in Ethiopia helps restore degraded soils and water resources while driving a rapidly growing green industry that creates job opportunities.
• Bananas in Southeast Asia offer shade for diverse home gardens, improving food security and boosting rural incomes.

To identify high-potential regions, the researchers examined data from the UN Food and Agriculture Organization across more than 30 countries that reported significant areas for bamboo or palm cultivation. From this, they aimed to pinpoint high-opportunity regions where grassy tree resources could facilitate accessible sustainability solutions.

“By acknowledging grassy trees as a unique form of growth, we’ve now set the stage for future research that will better illuminate their ecological and social value,” concluded Zheng.

Journal Reference:

Zheng, A. and Lu, M. (2025) Grassy trees: the neglected hybrids for sustainability. Trends in Ecology & Evolution. doi.org/10.1016/j.tree.2025.10.002.