It might seem like a stupid question but ‘Why do trees need water?’

It might seem like a stupid question but ‘Why do trees need water?’

Trees draw water from the soil and transpire this moisture through the leaves, this moisture carries with it minerals from the soil that has been absorbed by the roots. The leaf uses these minerals to help build new leaves and twigs, buds and flowers.

Just a quick note here that we need to differentiate between evergreens and conifers because of deciduous conifers (larch, taxodium, etc) and evergreen broadleaves (holly, winter oak, etc)

Some water is retained within the tree and absorbs the sugary, energy rich products of photosynthesis and the oxygen from respiration, returning both to the roots to help them grow, depositing some to all the parts of the tree as it passes, and collecting some in the heart of the trunk as storage for future use. Basically water performs the same function in trees as it does for human blood.

Now when humans get hot they sweat, emitting water on the skin surface that gets evaporated off taking heat energy away from the core of the entity. This exact same process happens in trees, the ‘sweat pores’ are found in highest concentration on the underside of leaves, but also in lesser numbers on the woody areas such as trunk and twigs. If this process is prevented by lack of water the organism, human or plant, will overheat at a cellular level and die. An adequate supply of water is therefore critical. This dangerous overheating is worse in some species and you will see reference to scorch in some text books. Of all my trees it is the beech that are most prone to scorch. The easiest way to deal with this is to keep trees prone out of the full summer sun and drying winds so they only have to deal with ambient air temperatures.

So let’s focus for a moment on the actual practise of watering. Once the soil in a pot has dried out the ‘standard’ watering from a hose or can will simply run off – you must quickly learn to recognise this sign as you tree will be in peril. Rectify by dunking the whole pot in water until all the air bubbles are gone, leave for another 5 minutes just to be sure, and then return to its home.


Collecting Trip New Years Eve 2013

Collecting trip for Wild Bonsai – New Years Eve 2013

Before reading anymore it is strongly recommended that everyone reads an excellent article by Walter Pall on the theory and ethics of collecting trees from the wild at:

The article focuses on collecting trees from the most inhospitable climates of the mountains. As we just don’t have the same quality of mountain as those Europeans it is quite possible for the enthusiast to find really good quality material much closer to home. Indeed this collecting trip was no more than 15 minutes from home! The key feature for me in looking for wild material is a combination of 3 factors – mature seed trees of the desired species, grazing and permission from the landowner.

Without the first of these there is just no point in combing the area as you will never find anything. Certain tree seeds can travel miles on the air but these generally do not produce high quality bonsai (Ash, Birch).  Without the second the tree seedlings will race upwards producing tall thin whippy stems racing up for the light against all the competition, so a ‘normal’ woodland setting provides thousands of young trees but the search for good bonsai yamadori is usually fruitless.

So on New Year’s Eve 2013 I set out to a spot I have identified whilst walking the hills over the summer as being of good potential. There area in focus is about an acre of open ground surrounded by stands of tree species regularly seen as bonsai (Larch, Scots Pine, Beech and Western Hemlock), all throwing their seed. The area is occupied over the summer months by cattle, this acts to trample taller trees snapping out any potentially leggy trees, they also graze the tender young shoots giving a pruning far more regular than most bonsai enthusiasts can manage!

Collecting trip landscape

I was not disappointed with the find of many trampled chewed sorry looking specimens, who at this particular visit were also sat in deep puddles after all the recent rain. Many of the trees were decidedly not healthy, being sick and yellow, these were all left to their fate out in the wild. However some were a lush green despite the treatment, these got a closer look as they would have the strength to withstand uprooting

.Collecting trip 2

The first find was a Western Hemlock about 60cm tall, a quick investigation revealed a good root structure, and great nebari and taper. When testing with the spade it was clear that the roots were spread horizontally over a stony layer of soil about 10cm deep. This was a great bit of luck as it exactly what we would try to achieve in bonsai with the wide spreading roots in a relatively shallow pot. There was a good fibrous root system close to the trunk and not many thick roots.

The tree was bundled up securely to keep a good quantity of forest soil. This serves 2 purposes, the first is that keeping this soil intact after severing so many roots will give the tree the greatest chances. Secondly the soil is perfect for this tree to grow in (any doubts check out the 30m tall specimens not that far away, it will also contain mychorrhyzal fungal associations that will act as additional roots for the tree. A lot has been said about these beneficial fungi but many people assume that there is only one type and that all they need to do is give a tree a dose of spores and then sit back – job done. Few realise that there are thousands of different strains of fungi, some that would be perfect with one tree will be totally incompatible with another species, therefore the only way to be certain is to take some soil from the wild and mix in with the new soil

On returning home it was potted up in a generously sized pot to allow the roots as much room as possible to recover. In order to balance the reduction on root I also pruned the branches to maintain the correct root branch ratio and take some stress off the roots. This also begins the development of the tree’s structure and you can see the informal upright shape and the taper in these before and after photos. The final photo was taken 6 months later after a second prune and well ready for a final prune of the year to get it ready for the winter – clearly a healthy tree!

Collecting trip WH

2014nov 004

Windswept trees as a bonsai image

At Raw Bonsai we are focused on taking our inspiration from nature and suggest that a truly convincing image can only be created in Bonsai if you understand the natural processes involved in shaping a wild tree.
Featured image

Let’s take a few moments to think about a convincing windswept image. I will start by introducing a windswept beech at the recent Bristol club show. Now fundamentally this is a lovely tree with a lot to recommend it, graceful movement in the trunk with a nice unusual shari, good root formation and well developed branching, not to mention a really good pot that brings out the silver in the bark:

So what is wrong with it?

The natural reaction to a tree growing in strong wind is for the buds in more sheltered locations to develop at the expense of those getting battered on the windward side of a tree. Any location will have a prevailing wind and the tree will lean away from this direction due to the cold dessicating effect of the wind, possibly even some salt laden spray in close to the coast. It is this and not the power of the wind that causes a windswept tree, unless it has simply an abnormal gust blowing an established tree over, but that is something quite different. So a bud in shelter will develop in a normal way, but instead of growing upwards any part of the bud tempted to do this will raise its head above the parapet and get buffeted by the wind, so instead it will grow into calmer air on the windward side fo the tree. Of course a slight steady upward growth will be possible but think of the correct growth like a staircase one step up and one step along.

The next image is a photo of a beautiful old hawthorn on the top of Dartmoor.IMG_9279

The whole image has a single direction of flow and the top is virtually flat as the wind sheers off new shoots. Of particular note is the lower branch, a young off shoot that has been able to develop quicker and therefore thicken up more than the older true trunk above it.

Take a moment now to compare it with the Bonsai image above and it becomes clear to me that a few of the branches to the right of the canopy really need to be removed to keep the flow in line with the angle started in the trunk, to do anything else is unnatural and unconvincing.

The problem for me is that the angle of the trunk suggests a very strong wind pressure throughout the life of the tree if it had grown in the top of a hill. A wind strong enough to create the dramatic lean would carry through to the finer twigs.

The same theory applies in a less windy place – consistency of the prevailing wind needs to be considered. This beech is set just under the brow of the hill and so the lower trunk is not in a location totally inhospitable but as the crown gets higher up it does get into the wind and the effects become more noticeable