Category: Environment

Walk along the circular pathway of the PACR Polytechnic campus, and you may come across a shrub that offers a delightful surprise. At first glance, it appears to be covered with white blossoms. But look closely, and you will notice flowers of two different colours blooming on the same plant at the same time, making it an especially attractive sight. The colour variation occurs because freshly opened flowers are white, while older blooms gradually develop a creamy-yellow hue as they age.

This fascinating plant is Madhu Karai (Catunaregam spinosa), an important native species of the tropical dry scrub forests of Tamil Nadu. Belonging to the Rubiaceae (coffee) family, Madhu Karai is a thorny shrub or small tree that typically grows between 2 and 8 metres in height. Its branches are armed with sharp spines, while the leaves are opposite, glossy and dark green. During the flowering season, the plant produces fragrant white flowers that gradually turn creamy-yellow before fading. It later bears round fruits that are green when young and become yellowish-brown as they mature.

Beyond its visual appeal, Madhu Karai plays an important ecological role. Its dense, thorny branches provide shelter and safe nesting sites for birds, while its flowers attract a variety of insects. The fruits are consumed by birds and other fruit-eating animals, which help disperse the seeds, allowing the species to regenerate naturally across the landscape. In this way, the plant contributes to maintaining biodiversity and strengthening the stability of dry forest ecosystems.