by Ian Brand

Wharfedale Naturalists Society

OUR native carnivorous plants have captivated me ever since my first encounter. It was while walking the Lakeland fells with friends the summer after my A-levels. A month’s holiday together, before we all went our separate ways.

I am not alone in being fascinated, Charles Darwin performed much of the early research into our commonest carnivorous plant, the Round Leaved Sundew (Drosera rotundifolia), and was the first to confirm its ability to trap and digest insects.

Plants just don’t seem designed to eat meat. They have no teeth or stomach, and unlike the Triffids in John Wyndham’s science fiction novel they are unable to pull up their roots and stalk their prey. Some flowers like Arums, and the appropriately named Catchflies, can temporarily entrap insects within their flowers to aid pollination. However, no flower can kill and then eat an insect. Instead, these plants turn to those tough, versatile workhorses, their leaves, which have been, in the case of Sundews modified for just that purpose.

The Sundew’s red, jewel-like leaves use bright colours and twinkling droplets of sticky goo to attract their prey then seize hold of it with the combined powers of superglue and acid. The leaves are covered with touch-sensitive glandular hairs or trichomes. Following the initial ensnarement, these ‘tentacles’ will bend towards the centre of the leaf to bring the insect into contact with as many stalked glands as possible, in a process called ‘thigmonasty’. Enzymes are secreted to digest the entrapped insect, following which the sugars, proteins and minerals are absorbed by the leaf surface.

All this effort allows sundews to live in nutrient-poor habitats, like the peat bogs found on our moors, where there is little competition from other plants.

Across the border in neighbouring Lancashire, in peat-digging areas, the plant was called ‘youth grass’. Here and throughout Europe, it was mixed with a variety of spices to make a liquor called ‘Ros Solis’, which was regarded as a source of youthful good looks. I cannot promise you eternal youth, but high summer is a good time to put on those walking boots and head for the hills and moors in search of sundews. I am still attracted to these insectivorous plants, just like early herbalists who were struck by the fact that the apparent ‘dew’ drops persisted even through the heat of the midday sun, which is of course how they came by their name ‘Sundew’.