Love your local nettles!
Nettles are everywhere at the moment and they are a huge resource for other wildlife: caterpillars of small tortoiseshell, red admiral and peacock butterflies use them as foodplants; ladybirds will enjoy a good meal on the aphids that hide on the plants; and the seeds are food for our seed-eating birds in the autumn.
Even the sheep and deer will eat them in moderation!
Flowers
The common nettle, Urtica dioica is by far the most widespread species in Assynt. There are records of the small nettle, U. urens but only a tiny number of locations are known.
The common nettle is a dioecious plant meaning it has male and female flowers on separate plants. The small nettle on the other hand is monoecious having both male and female flowers on the same plant.
You need to look close to see the different flowers and you need to be careful. As most folk can testify the common nettle has a much more common name, the stinging nettle!!
The flowers are borne in dense clusters. The male flowers produce small amounts of pollen which is carried by the wind to hopefully land on and pollinate the smaller female flowers.
If you have the patience, it is well worth watching a male plant release its pollen. The small flowers open to reveal four inflexed stamens. In the right conditions these, in very quick succession, flick outwards where they hit the open sepals causing the pollen containing anther to burst open and release its pollen.
We watched this happen on several occasions last week but trying to get it on camera is for another day!
The female flowers typically look white and open to reveal a small multi-pointed ‘star’. A cluster of these flowers is a really stunning sight and well worth searching for.
The sting
We can’t finish without going back to the stinging part in the ‘common’ common name.
If you get stung don’t take it personally, it’s simply the plant’s way of trying to prevent it being eaten by grazing herbivores.
The leaves and stems are very hairy, many of which are of the hollow stinging variety called trichomes. When these are touched the tip comes off and the hair becomes needle-like. It can then pierce the skin and inject histamine along with several other chemicals that cause the stinging sensation.
So please learn to love your local nettles and put the strimmer away.
David Haines
(words and photos)