Wednesday, July 11, 2012

Fern Ball at the Fern House

It was late in the afternoon. Johnson and I clambered down the tall Cullenia tree atop which we sat the whole morning enumerating epiphytic orchids. Hungry, weary of the cold gale and with hopes of ascending another tree, we grabbed our lunch boxes and gobbled up the stale Idly. We set off soon, in search of the next tree to climb. While doing so, we had to cross the Palaquium stream, a shallow stream that cuts across the ‘Green Trail’ which leads to a forest bungalow called the ‘Fern House’. Fern House, as the name suggests, is surrounded by lush growth of ferns of various types, including the tall tree fern. The idyllic Palaquium stream gets its name from the numerous Palaquium trees that are around it. There, on the low bushes, a clump of ferns caught my attention. The fronds were rolled into what looked like a clenched fist. 
The fern frond folded into a ball- © Seshadri KS 2009
The first thing that came to my mind was a story I had read a short while ago. The story, rather an incident, written by the noted Kannada writer, Poornachandra Tejaswi on his encounter with such rolled up leaves on a hot summer afternoon in the forest was fresh in my mind. We too, like the author were dumbstruck at the rolled up leaves. In the case of Tejaswi, he ponders over it over a while and takes it to an entomologist friend of his and they manage to open the roll and see eggs inside. Later the eggs hatch into what is identified as a Giraffe Weevil, with a disproportionately long head! The sense of wonder intrigues them to watch how the insect made the roll. After about two years, they happen to see it. The adult, by cutting off the mid rib, makes the leaf wilt and lays eggs in the tip and rolls it up quickly and lets it drop to the leaf litter where the eggs hatch and the adult bites its way out to freedom.
In our case, the young fern frond was rolled neatly and held together by some form of adhesive. We observed a few of such things around and decided to open up one of them! The leaflets were folded inwards and made into a neat ball with the top most leaflet folded and stuck inside holding it all together. For the untrained eye, it looked like the young fronds of ferns which are clenched like a ball before opening up. May be it was an act of deception by the insect. Inside the ball, there was a translucent spotted grub about an inch or two long and a lot of dark black pellets. The grub was probably of some beetle. On sensing its fortress to be breached, the grub coiled up. By the time we finished taking some pictures, the grub settled down and began to much away on the leaves. For every inch of leaf munched, there was a pellet dropped out from its rear! Such feeding machine! It was eating the ball inside out! 
Fortress breached! the leaf, the grub and the pellets © Seshadri KS 2009

Some silken threads were holding the folded leaflets together. Not knowing what to do further, we left the opened ball on a fern and hoped that the grub would survive. For over three years, I forgot about this incident till I saw one such grub in the stomach of a frog. The frog, called Nyctibatrachus had one of these grubs in its stomach content. Surely they must regularly be feeding on the grubs which are aplenty in ferns along the streams. 
The grub which I cared little to identify © Seshadri KS 2009
Sitting outside the forest and reminiscing about the incident, I am left with awe at the many ways in which various forms of life interact. An insect, that goes to great lengths to conceal its young one from being eaten up. A grub that eats the house made of leaves inside out. A frog that lurks beneath the leaves to grab a morsel of food. Truly a wonderful chapter in the eternal drama of life. I do not know what the species of insect is, nor did I make an attempt to find out. That the ecosystem has such wonders and mysteries for anyone and everyone to uncover and see is gratifying to me.

PS: Shyamal L tells me this "Some of us had reared this and it is a moth and not a beetle grub. Not able to remember the moth but check with the moth group, they might be able to identify the family based on the habit. The giraffe weevilsl make a nice tubular case and beetle grubs lack prolegs (false legs from the abdominal segments)".


  1. hi, lovely article. Just wondering how u got a look at the stomach contents of the frog, through the feaces?

  2. Truly am amazing world it is out there.. and a wonderful story u have shared.. :)

  3. Thank you so much for this post. I encountered fern balls today in the Great Smoky Mountains National Park and was mystified. After some Google searching I found your page and the answer!