ECOLOGY OF STINGING NETTLES
|Urtica dioica the stinging nettles with its stems and leaves densely covered with stinging hairs, which release potential pain-inducing toxins when brushing contact is made with them, is rarely eaten by rabbits. However nettle seeds have been found in cow dung so are eaten by cattle. Nettles have a higher nutritional value than the fodder crops amongst which they thrive. Nettles contain 5 times the copper and 1.5 times the iron content of fodder grasses and when dried may be consumed by cattle without ill effects. They are palatable to some species of snail (Salisbury 1961). The stings offer little defence against caterpillars. Up to 31 species of Lepidoptera butterflies and moths feed on stinging nettles, of which the adults of 4 species and 31 larvae feed (Davis 1991).
Urtica dioica is the food plant of the larvae of a number of attractive butterflies and other phytophagous insects. Nettles are home to a lot of butterflies like the Red Admiral Vanessa atalanta, Small Tortoiseshell Aglais urticae, Peacock butterfly Inchis io and the Comma butterfly Polygonia c-album. They use the nettle to lay their eggs on and when the larva hatch they feed on the nettles.
Red Admiral Vanessa atalanta
Small Tortoiseshell Aglais urticae
Peacock butterfly Inchis io
Comma butterfly Polygonia c-album.
Some moths also use the nettle patch to lay their eggs or feed, they include the Burnished Brass moth Diachrysia chrysitis,
Snout Hypena proboscidalis, on left and
Small Magpie Moth Pleuroptya ruralis,
Cream spot tiger Arctica villica, and Scarlet Tiger Callimorpha claminula, in the picture
Garden tiger caterpillar Arctica caja,
Buff ermine Spilosoma luteum, in the picture and Silver Y Autographa pulchrina,
Angle shades Phlogophora meticulosa, and on the right The Spectacle Abrostola triplasia,
Beautiful Golden Y Autographa pulchrina,
Nettle Top moth Anthophila fabricana and the Mother of Pearl moth Pleuroptya ruralis pictured below(Davis 1991).
(These images were produced by the British Moth Project, FLIKR and various universities Thank-you for letting me use these images)
The larvae of all of these species have been reported feeding on nettle foliage. In addition spiders, harvestmen, woodlice and snails feed on nettle plants.
|Jumping Plant Lice Trioza urticae use the nettle to lay theirs eggs, where they create a gall (an abnormal growth produced by the plant or other host which causes an enlargement on the plant that provides food and shelter for the host.)
Jumping Plant Lice
Some insects like the Nettle Weevil Phyllobius pomaceus, the Small Nettle Weevil Cidnorhinus quadrimaculatus, the Small Green Nettle Weevil Phyllobius roboretanus and the Green Nettle Weevil Phyollobius viridaeris only live in nettle patches.
From left to right The Nettle Weevil, Small Nettle Weevil
The small Green Nettle Weevil pictured below and Green Nettle Weevil
|Nettle Aphids Microolophium carnosum and Aphis urticata also live on nettles where ladybirds go to feed on them. Ants can be found protecting and herding aphids for the sweet nectar they secrete. Leaf-Mining Flies Agromyza anthracina; Agromyza pseudoreptans and Agromyza reptans use nettles for food by burrowing between the leaves.
Nettle Aphids Aphis urticata
Many birds like the coal tit, blue tit, siskin, reed bunting and bullfinch are attracted to nettles for the seeds and insects.
The work of the Nettle Leaf Miner