Make City Plazas Truly Ilonggo Again

The plazas of Iloilo City are lush, clean, and beautifully maintained. But beneath their manicured greenery lies a troubling reality: most of the trees that grow in these public spaces are strangers to the land they now occupy.

A new study by the University of the Philippines Visayas (UPV), presented during BIO-ILOILO 2025, makes this clear. Of the 183 plant species surveyed across seven major city plazas, only 34 percent are native. The rest are a mix of naturalized, cultivated, non-native, or even invasive species. That means our most iconic public spaces – La Paz, Jaro, Mandurriao, and Plaza Libertad – may look green and orderly, but they are ecologically disconnected from the land they stand on.

Dr. Resurreccion Sadaba, a biologist and co-author of the study, described the city’s current urban biodiversity as “moderate,” but this glosses over a deeper problem. Urban green spaces that are dominated by imported trees are not just incomplete—they’re ecologically unstable and culturally unrooted.

Iloilo’s plazas are landscaped, yes – but they are not “Ilonggo.”

This is not simply an issue of environmental science. It is a matter of cultural identity. Native trees like dapdap (Erythrina variegata), balete (Ficus spp.), narra (Pterocarpus indicus), and kamagong (Diospyros blancoi) are more than just species – they are silent witnesses to our history, carriers of local knowledge, and living links to Panay’s indigenous ecosystems. When we replace them with exotic ornamentals or foreign timber species like mahogany or acacia, we not only displace ecological functions—we erase our heritage.

The science backs this concern. Multiple studies – including a 2020 review in Biological Invasions – warn that non-native and invasive species weaken biodiversity by outcompeting local flora, reducing habitat quality for birds and insects, and failing to support native pollinators and soil life. Mahogany (Swietenia macrophylla), in particular, has been flagged as problematic in Philippine reforestation due to its allelopathic tendencies, which can inhibit the growth of understory plants and reduce biodiversity.

Iloilo is not alone in this struggle. Across the globe, cities have mistaken “green” for “good” – planting trees without thinking about what those trees actually contribute to local ecosystems. This is a form of ecological greenwashing. It looks like environmentalism, but it’s hollow. And in a climate emergency, we cannot afford to be performative. We must be intentional.

Fortunately, the UPV study doesn’t just diagnose the problem – it points to a hopeful path forward.

Among all city plazas, Arevalo stands out as a model. It has the highest percentage of native trees – 38 percent—and also exhibits higher tree density and carbon storage. According to Sadaba, this high density improves air quality and cools the microclimate. In simple terms, Arevalo Plaza is not only greener – it is healthier. It teaches us that biodiversity is not a luxury. It is a necessity for livable, resilient urban futures.

This is where agency comes in. The Iloilo City government, through the City Environment Office and in coordination with barangays and civic groups, has the power to shift landscaping policies away from ornamental aesthetics and toward ecological function. Sadaba rightly recommends a phased, selective management strategy: gradually replace invasive or non-native species with resilient native ones, while monitoring tree density, carbon stocks, and microclimate indicators.

Even more important is public education. Communities must be part of this transition – not just as spectators, but as active stewards. Schools can adopt plazas and contribute to tree inventories. Senior citizens who remember the old trees of their youth can guide the restoration of cultural species. Artists and historians can help design signage that shares the story of native trees and their role in Ilonggo life.

In doing so, we shift the narrative. Our plazas become more than beautification projects – they become centers of regeneration, learning, and pride.

The stakes are high. As climate change intensifies, cities like Iloilo will need every tool available to cool streets, clean air, retain water, and build resilience. Native trees offer these services – and more. They offer memory. They offer continuity. They offer belonging.

Let us not settle for landscapes that are merely imported, ornamental, and ecologically empty.

Let us plant roots that run deep in our soil, our culture, and our future.

Let us make Iloilo’s plazas truly native again.