Originally favoured for their rapid growth, low water needs, and use in afforestation, recent allergy concerns have prompted several states to halt planting and begin large-scale removal of Conocarpus trees
Published Mar 28, 2025 | 7:00 AM ⚊ Updated Mar 28, 2025 | 7:00 AM
Synopsis: Conocarpus trees, originally introduced for urban greening due to their rapid growth, low maintenance, and environmental adaptability, have faced criticism after research highlighted their negative effects. Initially promoted for their quick growth, use in afforestation projects, and low water needs, recent concerns, including allergies, have led to removal efforts in several states
“During the Haritha Haram initiative over the past ten years, officials have claimed that approximately 200 crore plants have been planted. However, it has come to my attention that a significant number of these include Conocarpus trees, which require minimal water and can grow in any environment. These trees absorb oxygen and release carbon dioxide, and even birds avoid perching on them. Such trees have been widely planted across Telangana. I urge the government to remove Conocarpus trees wherever they are found,” said Telangana Legislative Assembly Speaker Gaddam Prasad Kumar during the current assembly session.
He emphasised the need to eliminate Conocarpus trees, citing their potential threat to the environment. While there is no exact data on how many of these trees were planted under the program, the horticulture department noted that the Greater Hyderabad Municipal Corporation (GHMC) and the Hyderabad Metropolitan Development Authority (HMDA) procured them in large numbers for urban plantations.
This development follows similar actions taken by several states, including Tamil Nadu and Andhra Pradesh, which have decided to remove Conocarpus trees due to their adverse effects on public health.
Conocarpus trees, native to Africa, were introduced in India as an ornamental species due to their rapid growth and low maintenance requirements. Their benefits initially made them popular for urban greening projects:
Rapid growth and aesthetic appeal: Conocarpus trees are known for their fast growth, maturing into tall trees within just a few years. This made them a preferred choice for real estate developers and municipal authorities looking to quickly enhance urban landscapes and provide greenery in concrete-heavy environments.
Environmental commitments: Municipal agencies and industries often selected Conocarpus for afforestation projects aimed at carbon offsetting. The tree’s ability to thrive in harsh conditions, including saline environments, made it a viable option in areas where other plants struggled to grow.
Low maintenance requirements : Once established, Conocarpus trees require minimal care, needing only occasional watering. This low-maintenance nature made them an attractive and cost-effective solution for urban greening projects.
Adaptability to non-potable water: Conocarpus trees can grow using drainage and sewage water, making them suitable for areas with limited access to fresh water. This adaptability further contributed to their widespread use in urban landscaping.
Government initiatives: Several government-led plantation drives, such as Telangana’s Haritha Haram campaign, promoted the widespread planting of Conocarpus trees to increase green cover in cities and towns.
However, research has since highlighted their negative effects, leading several states to halt their planting and begin large-scale removal efforts.
“As a practicing allergist I have observed a significant lack of awareness about allergies in this region. There has been a noticeable increase in allergic conditions following COVID-19 infection or vaccination. Immunologically, I see both as similar. Whether it is a COVID-19 infection or vaccination, both involve exposure to the spike protein,” said Dr. Vyakarnam Nageshwar, Allergist and Immunologist, and President of the Hyderabad based World Allergy Foundation to South First.
He added that individuals who received the COVID-19 vaccine containing the spike protein are more likely to develop hypersensitivity conditions. This is because the spike protein triggers hypercytokinemia. When the body enters a hypersensitive state due to elevated histamine levels, it reacts differently.
“For example, an individual who previously had no reaction to pollen may now develop allergic responses due to increased histamine and cytokine activity. The core issue is that the immune system of an individual has been altered—whether fortunately or unfortunately—by either COVID-19 infection or vaccination,” he said.
He pointed, now comes the Conocarpus tree, which has been widely planted as part of afforestation efforts. “It is a species that should not be introduced at all. There are certain crops and plant species that should be avoided in urban areas due to their high pollen production, and Conocarpus falls into that category,” said Dr Nageshwar.
Conocarpus can lead to various respiratory problems, including asthma, allergies, colds, and coughs. These health concerns are especially pronounced during winter months when pollen levels are higher.
He said Conocarpus is being planted by municipalities and individuals alike, often for aesthetic reasons—to make homes and public spaces look greener. These trees grow rapidly, require minimal water, and can withstand high temperatures. That’s why they were selected in the first place.
Dr Nageshwar also said that lawmakers decision-makers should look beyond just the visible issue of Conocarpus trees, which have been widely discussed.
“The spread of Parthenium, commonly known as American Congress weed, is rampant. It can be found in ministerial quarters, the Chief Minister’s residence, VVIP areas—let alone in common spaces. It is everywhere. If you set down your phone, search for Parthenium on Google, and take a walk on the streets, you would call me back in five minutes and say, ‘Doctor, it is indeed widespread.’” he pointed.
He said that Parthenium is classified as the number one pollen-spreading allergen in the world. Unfortunately, we have overlooked its impact.
“Previous governments had some awareness of its role in allergies, asthma, and atopic dermatitis. That is why they conducted annual Parthenium eradication drives, burning the weed to control its spread. However, health concerns have now taken a backseat, and no one is addressing the issue, leading to a rise in allergic conditions,” he pointed.
“Regarding the Conocarpus tree mentioned by the Speaker—I completely agree with his concerns. However, the issue should not be limited to just that. I strongly recommend forming a dedicated committee, including allergists and municipal corporations, to assess and address the growing allergen problem in our cities,” said Dr. Naheswar.
Last year, Andhra Pradesh Deputy Chief Minister Pawan Kalyan ordered the felling of 4,600 Conocarpus trees in Kakinada. The state government, which had previously promoted the tree for green cover, has now stopped planting it. In several districts, the trees are being replaced with native species, and efforts are underway to educate nurseries and individuals about their negative effects.
In January, the Tamil Nadu government has officially prohibited the planting of Conocarpus trees in both forest and non-forest areas. The Principal Chief Conservator of Forest noted their harmful effects, prompting the Department of Environment and Climate Change to authorise district-level green committees to replace them with native species.
The government has issued an advisory instructing local bodies to remove Conocarpus trees from human habitations, hospitals, educational institutions, hotels, and resorts.
After large-scale plantation drives, the Gujarat Forest Department has now completely banned Conocarpus trees. Ecologists supported this move, highlighting reports of the tree’s pollen causing respiratory illnesses and negatively affecting native biodiversity, including insects, birds, and animals. The government has stopped planting Conocarpus in both forest and non-forest areas, marking a shift toward native tree species.
Harms soil & water resources: Conocarpus trees deplete groundwater and prevent the growth of other plant species under their canopy.
Health risks: The tree’s pollen has been linked to respiratory illnesses such as asthma, cough, allergies, and the common cold.
Limited ecological benefits: Cattle do not consume its leaves, and bees and butterflies avoid the tree, reducing pollination and biodiversity.
In response, various state governments are promoting native trees such as Neem, Casuarina, and Pongam, which are more beneficial to the environment and support local wildlife. These trees provide food for birds, enhance biodiversity, and are better suited to the Indian climate.
(Edited by Ananya Rao)
