Keston Windmill

Keston Windmill from outside.   31 August 2012.

This time, a post with no natural history, from an outing for the West Wickham Common and Spring Park volunteers, set up by the City of London Open Spaces Department.   Part of it was a visit to the Keston Windmill, a restored but not functional post mill just by the roadside to the south of Keston.

Keston Windmill.  The lever for engaging the gears.  31 August 2012.

We had  a very interesting and informative guided tour.  The mill is not often open to the public, so this was a great opportunity to learn.  For example, I knew that flour dust in air is highly explosive, but did not know how mills like this dealt with the threat. Here you can see that iron gears were opposed to wheels with wooden teeth, to prevent sparks.  

Keston Windmill.  The coarse stone lower grinding wheel.  31 August 2012.

There were two pairs of grinding wheels, one pair of coarse stone and one of imported fine stone.  This is the lower wheel of the coarse pair, used for grinding animal feed.  The finer one was for humans.

Later in the mill's life, people came to desire even finer flour, and so the output from the fine wheel had to be hauled up again and put through a sifter.

There was a good view from a small window in this part of the mill.  This last photo shows structures by the Thames near London Bridge and the Embankment.

View north from Keston Windmill.  St Paul's Cathedral and The Shard.  31 August 2012.

The Hammock Weaver

Spiders' webs on gorse, Hayes Common, 8 October 2010.

Photos from the past.  On a misty autumn morning, fine droplets of water cling to spider silk, revealing the huge number of webs on the gorse. This photo is from 2010; I haven't taken a better one of this phenomenon since. But a year ago I took some shots of the creature that makes all these webs; the Common Hammock-weaver, Linyphia triangularis.

Spider, Linyphia triangularis, Common Hammock-Weaver.  Orchid Bank, High Elms Country Park, 15 September 2011.

You can see the distinctive tuning-fork mark on its thorax. This spider weaves horizontal platform webs with strands running up to the foliage above. A flying insect that hits those strands might fall onto the platform below; and underneath it, the spider waits. It can quickly run along the underside and bite its prey through the web. The spider can deal effectively with substantial prey ... This one is in the same place I took the top photo.

Spider, Linyphia triangularis, Common Hammock-weaver, dealing with a relatively large fly.
Hayes Common, 22 September 2011.

Spring Park, Autumn

Spring Park on the morning of 5 September.

A couple of photos of Spring Park at the end of Summer.  I went back the morning after one of our moth-trapping evenings to check the exact location of the traps.

It was cool and bright.  The morning light picked out the hay in the meadow, which had just been mown.  It's managed as a wildflower meadow, so is mown late on, allowing the grasses and flowering plants to spread their seeds.  The hay is later removed, to keep a low level of soil nutrition.  That discourages the larger, rougher plants and grasses.

This path runs along the bottom of the wood parallel to the edge of the field.  That tree is a Sweet Chestnut; there are also big old Hawthorns along this line, and some magnificent Small-leaved Limes.

There are many paths through the wood.

Spring Park on the morning of 5 September.

Saltmarsh Plume

Saltmarsh Plume, Agdistis bennetii.  Riverside Country Park, 10 August 2012.

I said last time that Plume Moths rolled up their wings when at rest.  This is yet another species, an unusual one that lives only on salt marshes, and I have a couple of photos that show the rolling very clearly, quite distinct from any folding action.

The first photo shows the moth in the marsh.  It was very hard to see, resting in a Y-shaped posture rathet than the T shape adopted by most Plumes and looking just like a small twig, an extension of the plant.  If I had not watched it fly up and land I would probably not have seen it.  As it was, I knew where to look more closely.

Saltmarsh Plume, Agdistis bennetii.  Originally from Riverside Country Park, 10 August 2012.

Here is it on measuring paper.  The squares are 5mm across.  And now you can see the rolling of the near wing very clearly, even though that wing is a little out of focus due to the limited depth of field in this sort of photo. 

And now you have a good example of the sort of thing I find interesting!

Plume Moth Wings

Common Plume, Emmelina monodactyla.  Hayes, 4 September 2012.

Plume moths, belonging to the family Pterophidae, look very odd when they rest.  They roll their wings up into a tube and adopt this T-shaped posture.  I have posted a few different species of these in the past, which you will find if you search for "Plume."

This is the one most people see.  It's easily disturbed in daytime and its distinctive shape makes it a little bit easier to see than some small moths; in fact it's also bigger than most small moths!

I have seen it called a T-moth, for the obvious reason.  That seems a much more natural name than "plume" moth, but sometimes, when they land, they do not roll up their forewings, and then you can see something quite different.

Common Plume, Emmelina monodactyla.  Hayes, 9 September 2012.

Here is the same species near my garden light trap one night, and now you can see the array of fine hairs that make the wings look quite feathery. 

Autumn Moths

Two Lunar Underwings and one Black Rustic. In my garden light trap on 16 September 2012.

These species in my light trap are a sign that Autumn has arrived. 

For this photo I have placed them on one of the pieces of bark I picked up in the woods specifically for moth photographs.  The two on the right are the same rather variable species, Lunar Underwings, named for a small dark crescent mark in the centre of the underwing.  I'll put a photo below.  To check for its presence I had to stun one (chemically) and open its wings out.  I don't intend to do that to this species more than this once, as they always lose a few wing scales. But I am pleased to say that when I do do it, they always fly away afterwards.

The greyish one is clearly marked, but I thought the brown one might be a different, similar species, so that was the one I checked.  But the lunar mark was there, and now I know what forewing markings are critical for identification.

The Black Rustic is an easy one.  There are no other British moths with a combination of that dark colour, the slight glossiness, and the light outline around the kidney-mark.

 Lunar Underwing, Omphaloscelis lunosa, showing the dark crescent on the underwing.  Hayes, 16 September 2012.

Roe Deer

Roe Deer, Capreolus capreolus, across Keston bog.  Keston Common, 8 September 2012.

This scene is five minutes from a busy spot by a small lake, with kids and parents and fishers and an ice-cream van.  I was on a path along the edge of a small bog, one which was studied by Charles Darwin, and on the other side a Roe Deer was picking its way along the edge of the trees.  It's very good to see such large wildlife practically on the edge of suburbia.

This is when it's very useful that the lens I use for close-up macro photographs also works as a normal medium length portrait lens.