Saturday, 27 October 2012

Autumn Colour

Falling Leaves

      Years ago, I had a second hand G.P.O Morris 1000 van. In those days there was no passenger seat, the space being used for a toolbox instead. This wasn’t exactly the most social of arrangements, so I got hold of a seat from a scrapyard and placed it where the toolbox had been, with the intention of eventually bolting it in. However, intentions and actuality hadn’t crossed paths when I offered a female friend a lift home and she happily perched on the seat, oblivious to  its somewhat independent nature. We were chatting amicably when I made a rather abrupt start at some traffic lights. Turning to her to say something, I suddenly became aware that she had gone. Well, not exactly gone, but I was addressing her feet. The seat,  having toppled backwards, was now  in the process  of sliding, complete with occupant,  into the rear of the van.

      She was probably under the impression that this was some sort of passion waggon based on the Wallace and Grommit principle of dropping you into your trousers, only in reverse. Whatever she thought, I didn’t see her again.

Acer palmatum 'Dissectum Atropurpureum'

      At this point, neurons are whizzing through synapses in my brain like trains in the underground, carrying the message that the phenomenon of  Morris 1000 seats disappearing  into the rear of vans is similar to that of the leaves falling off trees in autumn. Don’t worry if you missed this connection – some of our synapses work differently.
      The leaves change colour because the onset of cold weather breaks down the chlorophyll in them. Chlorophyll is what makes them green and this green masks the yellow, red, orange and purple pigments also present. When it disappears therefore, these colours are allowed to briefly shine through like the sun when we open the curtains or shed the sunglasses. Eventually however, the tree sheds the leaves because they can’t function as food factories in the cold. They fall to the ground, are broken down by myriad fungi and other organisms, and eventually return their nutrients to the tree via its roots. The plant then puts out new leaves and the cycle continues.

Marie Louise Gardens


 So by now you’ll understand the similarity to what’s happening in the van. When I stop abruptly at the next set of lights, the seat shoots forward and, when it hits the edge of the old toolbox, tips the  girl back into the starting position. It’s all about cycles.

Friday, 19 October 2012

Water Fern (Azolla filiculoides)


      Knowing when to stop is a problem confronting a lot of situations in both human and plant life. In my case it was with do-it-yourself: my wife and I had a system; she would think up jobs and I'd do them. Usually with the accent on 'do'. On one occasion, some lino needed laying in the bathroom. We had not been in the house long, having got a mortgage at the extreme end of what we could afford. It was at that time in the '80's when the chancellor was putting up the interest rate three times before breakfast and we could only just afford to eat. The lino therefore was a luxury and I was under great pressure not to cock it up.

      With great concentration, I made a plan of the bathroom and measured the positions of the bath, toilet, sink, etc, then drew their outline on the lino before cutting out the shapes. The measurements were exact, however the fact that I drew them on the back of the lino ( I didn't want to mark the pattern) meant that, when it was rolled into position, the bath was on the left hand side of the room, the lavatory and wash-basin were also on the left but all the cut-outs were on the other side. This left me with the options of either throwing myself out of the window before my wife found out, or to piece it together. As the extension roof was just below the window, it seemed likely I'd go through that and simply end up doing more repairs, so I 'invisibly' patched the lino. I thought the jig-saw puzzle effect was quite original. Unfortunately, my wife didn't.

Water Fern

      Water fern (Azolla filiculoides) is one of many plants which, like me, don't know when to stop. Each tiny plant breaks into smaller sections, replicating itself at a prodigious rate, so that large surface areas quickly become covered. This was so extreme in the pond at Fletcher Moss Gardens where I worked, that one old chap, thinking it was a lawn, tried walking across it. Unfortunately, Jesus he was not, and only his hat indicated the route of his submerged wanderings. The fact that the water fern cuts out light means that oxygenating plants growing below are unable to photosynthesise, so they die and the general health of the water suffers. However, a positive aspect lies in the fact that it is able to 'fix' nitrogen, a valuable plant nutrient, from the atmosphere. As a result of this, it is grown in rice paddies to enhance growth of the crop. Equally, it can be removed from your pond and used as an effective green manure when incorporated into beds.

Pond at Capel Manor Gardens

Coot finding it hard work


As the days grow colder, the plant takes on an attractive purple colour for a number of weeks, before producing buds which drop to the bottom and overwinter away from ice. Originating in North and South America, it causes problems in Australia, New Zealand and various other countries. It is not to be confused with our native common duckweed (Lemna minor), which has a similar carpeting effect on water. According to Richard Mabey in Flore Britannica, this used to be known as Jenny Greenteeth, 'an amorphous monster that would suck children into the depths if they wandered too close'. The story was probably used to keep youngsters away from dangerous water.


      Being aware of a plant's propensity for spreading is important and it is well worth checking before subjecting yourself to another problem which 'seemed a good idea at the time'.

Saturday, 13 October 2012

Woodlice - Friend or Foe?

What harm do they do?

      Woodlice are one of the commonest, or at least most easily seen, residents of the garden. They occasionally do a bit of damage in the greenhouse by having a nibble at young seedlings but established plants are not bothered by them. Their presence is more a criticism of the gardener for presenting them with good living conditions in the form of places to hide.
      It seems a shame that, because something has more legs than us, the reaction of many people is 'how do I kill 'em?' The fact is that woodlice mainly eat dead organic matter. This means that they are  part of nature's wonderful recycling system whereby this food is reduced, along with the work of other organisms, to compost. The compost enables more plants to grow and is an example of how even the smallest, seemingly insignificant, creatures play a much more positive role in preserving life on Earth than we do, with our polluting, resource- exhausting ways.

      They crawled from the sea millions of years ago and since then haven't evolved much: still breathing through gills, they will usually be found in damp places, under stones or rotting leaves, where they can retain a 'skin' of water. Apparently these gills are in their knees, which probably means they aren't religious because, in kneeling to say prayers, they will asphyxiate themselves. Ancient relatives, a foot in length, can still be found 6,000 feet down in the Atlantic and The Sea Life Centre in Blackpool have some on show. There are many different species frequenting gardens but basically they share the same characteristics, apart from the foot long bit.

      My selection of wildlife pictures includes quite a few of insects mating, leading my wife to label me an insect voyeur. Sadly I have none of woodlice in a compromising situation. The closest I came was when on holiday in Presteigne, on the border of Wales: I was walking along a lane about the width of a car. The sides were banked and full of wildflowers, while in the distance a cuckoo was calling. The sunshine and blue skies seemingly completed this idyllic picture until my senses reached even further heights when, rounding a corner, I came across two woodlice in flagrante delicto  on a vigorously bending blade of grass. My excitement was even greater than theirs: I fixed my camera on the tripod, focused, adjusted for depth of field and was about to shoot when their exertions overcame them and they fell off.

      Some species of woodlice were called pill bugs in days of yore. This was because, when touched, they roll up in a ball. People suffering upset stomachs would swallow one in order to clear up the problem.

      Might be worth a try.

Wednesday, 3 October 2012

Cambium - The Living Part of a Tree or Shrub

Diagnosing Death

Because a plant looks dead doesn't necessarily mean that it is. Woody plants - trees and shrubs - can often display all the symptoms but not actually be in the same realm as the Monty Python parrot: the living, growing, part of a tree trunk is immediately under the bark and is called the cambium. It is green, which is a diagnostic feature to look for if in any doubt. Late spring and early summer are the times when most healthy plants are mistakenly consigned to the compost heap. Because it is late coming into leaf it is easy to think that the winter has put paid to it and the only way is out. I don't fall for this one any more. Simply by scraping a thumbnail of bark back will show whether the cambium is still living and green, or brown and dead. If it is green, then a bit more patience is called for, giving it time to belatedly get out of bed.

I was surprised to learn that hamster death symptoms are similarly not straightforward. My son was in a house- share when one of the sharers - a girl - came banging on his door in floods of tears. It seemed her hamster had died and he, known to be compassionate where young women are concerned, was designated as undertaker. He duly wrapped the deceased carefully in kitchen foil, descended to the yard, and consigned it to the wheely-bin. While this sad ceremony was taking place, the bereaved flatmate was tearfully informing her boyfriend of the death over the phone. It turned out that the boyfriend was a bit of a wildlife expert: "it isn't necessarily dead," he informed her, "they hibernate. Warm him up a bit and he'll probably wake up." This learned information was immediately imparted to him when he returned from the interment and he was promptly dispatched back to the yard to perform an exhumation. The animal was then placed gently under the grill on a very low setting. Unfortunately, Jesus he was not, and he remained in the same state as the aforesaid parrot.

Hollow oak at Lingfield, Surrey

Anyway, cambium consists of the tree's arteries: water, nutrients and sugars are pumped up and down through them and each year they die and new ones are formed under the bark as replacements. This means that the centre of the trunk is dead material, it also explains how the rings seen in a cut trunk have been made: at the beginning of the growing season wide arteries are formed to accommodate the rush of water, then as the summer progresses, growing drier (theoretically), smaller ones replace them, creating the different textures which appear as rings. Counting them will give the age of the plant. The appearance of the rings can also give an idea of the amount of rainfall in a particular year: one tree, a bristlecone pine living in The White Mountains of California, displayed 1,100 microscopic rings in 5 inches, mirroring the dryness of the area where it lived.

Hollow, live tree in Dunham Park

Knowing about the cambium is useful not only in determining whether a plant is alive. French walnut growers would, after a bad harvest, beat the tree with willow wands. This would cause neighbours to think about calling for the men in white coats but, amazingly, the following year's crop would be abundant. The reason for this was that beating damaged parts of the cambium, limiting the flow of growth-promoting sugars to the roots. This meant that sugar, continually produced in the leaves, had now to be re-routed somewhere and the only option was  to the upper parts of the tree. Here it was used up in promoting more flowers and fruit. We now have a more sophisticated way of doing this by bark ringing. This is the removal of a strip of bark, about an inch wide, from perhaps three quarters of the trunk's diameter. Beware though, if you ever try this, completely circling the tree will lead to it being in the same state as the hamster.