Friday, 7 February 2014

Acer pseudoplatanus (sycamore) & tar spot

Fear of Flying

Bert's Quadrocopter
There's still a child in all of us, regardless of age but some of us have the fact more prominently displayed than others. Take blokes with model trains. Poor kid gets one for Christmas then can never play with it because dad got there first. My mate Ged got a bit more sophisticated and built a model helicopter. I think the kit cost him about £150 a few years ago and that was quite expensive then.

"Radio controlled", he told me "come round when I've done it and you can see the inaugural flight".

About three months later I got a call from Ged informing me that he was ready for the first flight, so we took the impressive looking model into a large field in Derbyshire and prepared for take-off. A small audience of cows stood in a group to one side of us, edging closer in the nosey ways that cows have.

"It takes a bit of expertise", he said, "you've not got just the main rotors to control - the back one has to be going at the right speed to stop the body spinning". He was right about that, as we were to find out. It seems a shame that he couldn't get a bit of practise in before consigning his creation to aviation history.

The machine was placed on the ground and we stood back as Ged started fiddling with the controls. Nothing happened at first and he had to take the front off the control panel and 'adjust the wiring'. Then he tried again, pressing the lever which, I assume, said 'up'. He had done the adjusting with devastating success, because the rotors immediately started turning slowly, then suddenly became a blur, and the thing shot up to a height of about a hundred feet at a speed which would have turned a crew of Apollo astronauts green. The five cows stared upwards in amazement, bringing to mind that story of the penguins watching a plane take off during the Faulklands war, then falling over backwards when it got too high. It stayed there poised for a moment, then the fuselage (if that's the right word) began rotating in sympathy with the rotors. Ged juggled impressively with his control panel (which would also have dazzled the Apollo pilots) and, after some time, it stopped spinning and reverted to hanging in the air with the small end (tail?) upwards. As was his way, Ged then cracked on it was meant to do that.

"It'll do loop the loop according to the blurb", he informed me, and it proceeded to just that. That is, it got the first part of the manoeuever right, swooping downwards, but omitted the other bit where it zooms up and completes the circle upside down. In spite of Ged's frantic control - juggling, it continued heading vertically down towards us at frightening speed. Our eyes must have grown bigger in proportion to its proximity and then, at the last moment, we dived to each side in in a way reminiscent of that scenario in the opening credits of 'Father Ted'. One of the cows uttered a bellow that I took to be a bovine version of 'bloody hell!' and they stampeded into the distance. I've often wondered if the farmer ever worked out why the milk came out curdled that night.

I don't know how many pieces there were in the kit that Ged made the helicopter out of, but I can guarantee there were far more when it concluded its maiden flight. When, from a prone position in a cow pat, he blinked thoughtfully and uttered a philosophical "oh well, back to the drawing board", I vowed that I wasn't watching the next solo flight without the comforting surroundings of an air raid shelter.

And, as if Ged and his helicopter wasn't enough, another mate, Bert, made a quadrocopter (my name for it). This is a circular central piece, like a CD container (in fact I think it was a CD container), with four arms emanating at right angles to each other and supporting rotors at the outermost end. The birth of this was more prolonged than that of the helicopter, taking almost a year to get to the flying stage, during which time one of the rotors amputated the top of one of Bert's index fingers. He had a few successful tests in the garden before lugging it down to a large, cowless, field somewhere on The Wirral. I was fortunate enough not to have been present at this christening. According to his report, it performed beautifully for about ten minutes, hovering perfectly steadily, and dutifully moving above the field under his guidance. Then, at roof height, it began slipping sideways, travelling across the field unresponsive to the controls before disappearing over the fence of a nearby house.
Test flight
He waited for a crash indicating a broken window, in which case his sixty five year old legs would have propelled him in the opposite direction at a speed you'd hardly expect. However, there was a prolonged silence, so he crept up to the fence and peeped over. The quadrocopter was still in the air, dangling on a washing line. One rotor was entwined in a bra:

"a 38 incher", he informed me (where the hell did he get that expertise) "you could have made a lovely double hanging basket with it".

Making sure there was no one looking, he sneaked over the fence, untangled the machine then legged it, having no wish to meet the owner of the bra. Not under those circumstances anyway.

That's what I mean about the child in all of us, though I suspect women would say it only applies to blokes.
Sycamore 'helicopters' made of willow stems
The tree gardeners love to hate is the sycamore, whose seeds look like helicopters as they make their way to a potential spot for germinating. On a windy day they can fly as far as 350ft from the parent, making this a brilliant seed dispersal method - a point well appreciated when they start popping up in your garden and you haven't got a tree. Their strap - like leaves quickly become strongly rooted saplings and early removal is essential if you want to avoid a hernia. They can, of course, go much further if ingested by an animal, then excreted.
The real thing
Funnily enough, it's a close cousin of the decorative Acer which is at the other end of the appreciation scale. It's Latin name Acer pseudoplatanus  (pseudo -false and platanus -plane) indicates a close resemblance of the leaves and bark to the plane tree. Introduced in the middle ages, it has, until recently, been seen as a second-rate immigrant which supports little wildlife. However, it's now recognised that the fallen leaves have the effect of causing the increase of earthworm populations and wildflowers, like woodruff and wood anemone, thrive in the loam created. The fact that the tree is a magnet to aphids is now seen as a positive in so far as it is important for providing the food for insect - eating birds like house martins.
Tar spot on sycamore leaf
In late summer the leaves often become dotted with black patches. These are caused by a fungus (Rhytisma acerinum), which, though unsightly, doesn't seem to harm the tree. Nail galls, those tiny growths which erupt from the surface of the leaf like miniature fingers, are caused by eriophyd mites feeding. They can attack a single plant cell and this causes the surrounding cells to enlarge and multiply, ultimately forming the gall. In spite of these apparently disfiguring features of the foliage, the wood is much valued for its properties of hardness and attractive whiteness. It's a favourite for use as tables, being so close-grained and easy to clean.

Although we think of sycamore as a dark tree, in spring the dangling yellow flowers can compete with many ornamental trees. Its seed aerobatics are an attraction to children and, who knows, may have initiated the idea for the helicopters which led ultimately to the debacle with Ged's model. So maybe the tree isn't quite the villain we thought it was.

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