Sonkadi (Pentanema indicum) is a short spreading herb which you see almost everywhere in India when it is not too dry. In the monsoon it grows all over the Sahyadris. Clusters of these yellow flowers can be found in roadside ditches, wastelands, as weeds in untended gardens. It is often used in folk-medicine, to cure everything from colds and fevers to stomach pains. In fact so many useful chemicals have been extracted from it that there are studies on how to grow the flowers in the lab without having to grow the whole plant.
Why is it so hardy and widespread? Where did it come from? After a lot of search I found that these simple questions are too complicated to answer now. It turns out that this species is a member of the largest family of flowering plants known. This is the sunflower family, called Asteraceae. Within this family is a tribe called the Inuleae whose core members have yellow hermaphroditic flowers. This is where the Sonkadi belongs. This is a partial answer to the questions that arise in my mind whenever I see these hardy plants poking out of inhospitable spots.
I’ve written about the world heritage Kaas plateau before. I went back there over the weekend. The volcanic rock barely holds any soil, and what little is there has little nutrient. The plants that one can see here have evolved in this hard environment. As a result, this 10 square kilometer area at an altitude of about 1.2 kilometers is an island mountain: the flora here is isolated from flora in other plateaus in the region. There’s a brief but glorious flowering at the end of the monsoon. By all accounts the flowers change almost every week.
The most famous plant here is the Topli Karvi (Strobilanthes sessilis) which blooms in mass once every seven years. Last year this was in bloom. This year the general view (see photo above) did not show any of the bright blue flowers of this bush. One had to search hard for the few isolated and idiosyncratic bushes of S. sessilis which flowered this year. Instead the landscape was full of patches of white globular pipewort (Eriocaulon sedgewickii) mixed in with the vivid colours of the carnivorous purple bladderwort (Utricularia purpurascens). In other places we patches of the yellow sonkadi (Pentanema indicum) mixed in with the violet rosemary balsam (Impatients oppositifolia). You can see all four species in the featured photo.
This week the balsam outnumbered everything. Most green patches had highlights of violet. Maybe by next week the sonkadi will dominate.