Smartphones, Social Media, and Science: Patterns of Flowering in Three Indian Trees

Across India, trees mark the passing of seasons in their own steady ways. They shed and regrow leaves, burst into bloom, and bear fruit in short surges or prolonged phases that are cyclical, seasonal, and shaped by local climate and geography. Many of these events have long been quietly recorded. People photograph flowering trees on neighbourhood walks, share images on social media, or log observations through citizen science programmes. Individually, these records may seem incidental, but together they form a growing archive of how trees flower across India.

During the COVID-19 pandemic lockdown, this data took on new significance for ecology research. Fieldwork was either constrained or impossible to conduct. Routines were disrupted. Researchers and students turned their attention to existing data. The natural world, after all, had not paused. Trees continued to leaf, flower, and fruit, offering an opportunity to ask larger ecological questions using records already created by everyday observers.

One such study published in the Journal of Biosciences in 2025 used social media and citizen science portals to examine how the flowering times of three widespread tropical tree species vary across India.

What makes the work interesting is not just the results regarding the ecological patterns of tree flowering, but how it came together — combining public data from social media, digital photo repositories, SeasonWatch (a citizen science initiative), and the curiosity of an undergraduate student, a schoolboy, and a plant ecologist.

Science powered by public data

Bhavya Kriti and Sidhharth Mahesh worked on this during the COVID-19 lockdown. Kriti, then a college student in Ranchi and currently pursuing a PhD at the Centre for DNA Fingerprinting and Diagnostics (CDFD, Hyderabad), took up the project to explore her love for ecology and pollination. Mahesh, then a school student in Bengaluru and son of well-known ecologists Jayashree Ratnam and Mahesh Sankaran, chose to work on the project to delve into something at the intersection of ecology and society. Mentoring them was Geetha Ramaswami, a plant ecologist who leads the SeasonWatch programme and has long advocated for citizen science as a bridge between everyday observation and ecological research.

The study focused on three ecologically important and familiar trees — Bombax ceiba (red silk-cotton), Butea monosperma (flame-of-the-forest), and Cassia fistula (Indian laburnum). All three are widespread, culturally significant, and visually distinctive, which made them ideal candidates for observation by non-specialists.

The work used two sources of publicly contributed data. One from SeasonWatch, a pan-India citizen science initiative in which volunteers repeatedly observe the same trees over time, recording the presence and abundance of flowers, fruits, and leaves.

“SeasonWatch was started in 2010. At that time, citizen science was just up and coming as a field across the world. The idea was to engage people to observe trees and understand they respond to climate change. To date, the chief goals of SeasonWatch are to generate scientific data and educate the public through observation”, says Ramaswami. 

The second dataset came from photographs of flowering trees, often taken during routine walks or travels, shared between 2018 and 2021 on social media platforms, biodiversity portals, and digital photo repositories.

“One of the biggest challenges in doing this work was extracting information on the location and date of the observation from these repositories. It had to be done manually, and that was a lot of work”, says Kriti.

While social media images offered broad geographic coverage, SeasonWatch data provided continuity, capturing peak flowering and seasonal shifts through repeated observations.

Three trees, one question

The central question was simple — do trees of the same species flower at different times across India’s latitudinal (north-to-south) gradient?

The short answer is yes — trees of the same species have different flowering patterns across north and south India, adjusting their schedules to regional environmental conditions.

The red silk-cotton tree flowered mostly between December and March. Trees in southern India bloomed from December through February, while those in northern India flowered later, between February and March, sometimes extending into April/May. Long-term SeasonWatch data further revealed that at lower latitudes, a few trees flowered sporadically outside the main season, whereas northern populations showed a much tighter flowering window.

The flame-of-the-forest showed a similarly seasonal but more sharply defined pattern. Across much of India, flowering was concentrated between January and March, a characteristic late-winter display. However, in southern India, peak flowering began earlier (in December) and in some cases, even in June, while trees in the north had closely synchronised flowering during January–March, occasionally extending into April.

The Indian laburnum had the broadest flowering window of the three species spanning from late February through July, with peak flowering being clustered between March and June. In southern and Central India, trees often flowered almost year-round, whereas in northern India, flowering was more seasonal, typically peaking between April and June.

Together, these patterns show that latitude affects when flowering begins, how long it lasts, and how synchronised it is. Trees in north India, with stronger seasons, flower within shorter periods, while those in South India show longer and more flexible flowering. This north–south pattern highlights the adaptability of tropical trees.

Why flowering time matters, especially now

Phenology is the study of the timing of life cycle events such as flowering, fruiting, and leafing. Flowering phenology is especially important because it affects pollination, seed production, and the survival of tree species. But shifts in flowering can also ripple outward, affecting insects, birds, mammals, and ecosystems that depend on trees and their flowering and fruiting cycles.

“Currently, we don’t have any large-scale data on tree flowering for India. Also, given climate change issues and that trees are so dependent on the climate for cues to flower, this is a really important topic to study,” explains Mahesh.

As climate change alters temperature and rainfall, changes in flowering times may disrupt plant–pollinator relationships and affect entire ecosystems. Establishing baseline flowering patterns is therefore crucial, and this study does so for the red silk-cotton, flame-of-the-forest, and Indian laburnum trees. 

The study also shows that valuable ecological insights can emerge from shared observations, even without long-term historical data, highlighting that science can begin far beyond the laboratory.

“This is a neat piece of work, and I really appreciate the fact that the authors used data from two different sources to demonstrate the patterns in phenology," says Dr Jayanti Ray Mukherjee, Associate Professor at Azim Premji University, who works on plant ecology. "It would be interesting if this work continued for more species of trees and for longer, to further understand these broad patterns in phenology (flowering or fruiting) which may have significant long-term impacts under the changing climate", she adds.

“What’s exciting to me about this project is that a public repository of images that was contributed without the intention of a “scientific endeavour” was able to complement data that was collected with a purpose. This sort of “incidental information”, where data being collected for one purpose, also ends up collecting subsidiary data that is useful for something else is reminiscent of a “zero waste” situation, which I find delightful”, says Ramaswami.