Saturday, 29 September 2012

We heard bats

Sunset over Thornbury Leisure Centre. 
On Thursday evening just after sunset about 25 of us were led round Filnore Woods by Laura of the Avon Bat Group.  We were given a bat detector each, supplied by South Glos officer Chris Giles and we heard the bats.  Some of us even saw them too.
Down by the Sita Sort-it site where the lights attract insects, we heard the chip-chop call of Noctule bats (Nyctalus noctula) Britains largest bats, with a wingspan of up to 16 inches (400mm).  They are the first to come out in the evening and fly quite high in the sky.  They have rather nice little faces too.
In several places we also heard Pipistrelle bats (Pipistrellus pipistrellus).   Laura described it as a "wet slapping" sound. These are the most common bats in Britain.  You may see them flying in your garden or even roosting in your attic.  They are completely harmless and odour-free, by the way.  We found them at Filnore in the tree nursery field, by the footbridge,  at the bottom of the slope below the pylon and near the main entrance.  They like to fly near or under tree canopies to hide from owls.  
On "useful links" on the right of this page you will find links to
 a short video of Bill Oddie with a Noctule at
And "Pipistrelle bat sonar, Catford"   to hear the wet slapping call. 
There's loads of stuff on google and on YouTube,
but to  hear them out in the field was really quite exciting.

Monday, 24 September 2012

Hemp agrimony

Butterflies get high on this plant.  It grows tall and its pinky mauve flowers with white whiskers give a touch of colour to the end of summer. 
The leaves look a bit like hemp which gives it both its English name Hemp Agrimony, and its Latin name Eupatorium cannabinum, like cannabis.  It's no good for smoking though.

Monday, 17 September 2012

Challenging specks

These speckled wood butterflies are very common in the dappled shade of the woodland edge at Filnore.  They perch perkily on leaves, waiting to investigate and challenge any other butterfly or even a human.  You often see two flittering head to head in mid-air.
I saw one chasing a large white butterfly away and they are certainly cheeky enough to fly up and give you a good look.  These are the males who patrol their own little territories and drive competitors away.  You can still see plenty of them if you visit the woods.

Saturday, 15 September 2012


Now at the end of its flowering season, we have a huge swathe of magenta flowered rosebay willow herb (Chamerion angustifolium) growing in the nursery field.  Most of it has finished flowering and is producing the fluffy white down which carries the seed all over the place.  Annoyingly it often lands on the blackberries you want to pick because they both appear at the same time.
Rosebay is known in North America as fireweed because it often colonises burnt ground.  It was one of the first plants to grow on bomb sites during the second world war and cheer them up a bit.
Once established it spreads not only by seed but by spreading roots which send up new stems the next year.  This is why we have so much in the nursery field.  It's beautiful but you can have too much of a good thing so we shall be cutting some of it back to give other plants a chance too.

Friday, 14 September 2012

Gliding Peacocks

The Peacock butterfly (Inachis io) is one of the easiest to identify with its strong flight and peacock tail "eyes" on the wings.  But when it folds its wings up over its back it is hard to spot as it is almost black  You will probably have seen them on buddleia bushes where they gorge themselves on nectar.
This one was photographed by Martin Bradford at Filnore, feeding on a teasel.
Peacocks appear quite early in spring after hibernating in hollow trees, garden sheds and similar dark crevices.  The eggs are laid on nettles and the black spiny caterpillars feed in groups under a silken web until they are nearly mature.

Sunday, 9 September 2012

A rose by any other name . . .Guelder Rose

The guelder rose is not a rose at all.  It is actually a Viburnum.  It can grow into a large bush but never a tree, as the stems are too weak.  Here is one at Filnore with Rosebay Willow Herb around its feet.
The leaves are a bit like maple.
The berries are shiny orange or scarlet - a feast for birds.

Friday, 7 September 2012

Scabious and Knapweed

These colourful Knapweed flowers of late summer are good nectar sources for butterflies, bees, wasps and other insects to end the summer with a feast.  Each flower head is composed of multiple florets with the outer row much longer, giving that tufty appearance.
Scabious flowers bloom at the same time as Knapweed, and also have flower heads made up of several florets.  But the outer florets of Scabious are not tufty like the Knapweed