Trees and Woodland
Planting and managing trees and woodland
When planting a tree, the first thing to think about is the location. Is it appropriate for a tree or would shrubs be better? If the site is suitable for a tree, think about the mature height of the tree and how much growing space there is. This will help you to decide whether to get a small, medium or large growing species. You also need to think about your neighbours land - don't plant a tree where there might be problems in the future, or where the tree might cause damage.
Trees can be planted in a variety of sizes and forms. Some are better than others at successfully establishing and some are more expensive than others. Sizes can range from:
- a transplant - usually a two year old seedling which is 45 to 60cm tall, and which are fairly cheap
- a semi-mature tree - with a trunk girth larger than 20cm and a height over 6 metres, which are very expensive
You can buy trees bare root (cheaper), root-balled or in a container (expensive).
When to plant a tree
The best time to plant a tree is in the dormant season between November and March. They can be planted bare root during this time. You can plant them at other times, but they will have to be in a container, and will need extra care, particularly watering.
Most trees (except transplants) need to be planted in a pit. It should be dug wide enough and deep enough to accommodate the tree roots. It is important to make sure there is enough drainage, and to make sure that you plant the tree at the same depth at which it had previously been grown. Larger trees will need staking to hold the roots firm while they establish. The stake should not be any higher than about 600 to 1000 mm long above ground - this is so that the tree stem has some flexibility and can develop properly.
Woodland is usually planted using transplants. These are notch planted between 2 to 3 metre centres. Notch planting involves cutting a T or L shape in the ground, lifting the soil, placing the roots in the gap and then firming down. Many hundreds of trees can be planted in a day this way. They are protected by a rabbit spiral or a deer tube which is held by a cane or small stake. The area around the base is kept free from weeds to allow the tree to grow without any competition. This is usually done with herbicide, but mulch-mats can also be used.
Planting the tree is just the start of the process to establish a healthy mature tree. Trees need to be checked regularly to make sure they have not loosened in the ground, that any ties to the stake are in the right place, that the trunk is not rubbing, and the ground around the tree is still weed free. If the weather is dry, the tree should be watered. Applying a mulch of compost, bark, old carpet or a mat will help to keep the weeds at bay and keep the ground moist.
Trees and woodland generally do not need anything doing to them on a regular basis. However, when trees are grown close to buildings or other infrastructure, there can be conflict between the two, and action may need to be taken. This is why it is important to plant the right tree in the right place.
Trees live a long time. During their lifetime the use of land around them can change and problems can develop which weren't there originally. For example, housing may have been built after the tree was planted and there may now be issues such as shading or restricted TV signal. Appropriate pruning can usually overcome these issues.
When a young tree is planted, the first two or three years are crucial. Key tasks are watering, weeding and keeping the tree firm and upright. Minimal formative pruning might be needed to maintain a single leading shoot.
Trees are susceptible to hazards which can damage them and which may result in the need for pruning or even felling. Snow falls and high wind can damage branches or the whole tree. Lawn mowers or thoughtlessly stored material can cause physical, chemical, or physiological damage.
Common pruning techniques are:
- Crown lifting - this is the removal of lower branches to increase ground clearance leaving more clear trunk
- Crown thinning - this is the removal of smaller branches to open the crown to allow more penetration of light and wind
- Crown reduction - this is done very carefully by cutting back to a suitable side branch to make sure the future shape and health of the crown is not compromised. It is NOT the same as topping. Topping removes a significant portion of the top of the crown, leaving flat-topped cuts which can decay. Topping makes the tree unsightly and structurally weak and is expensive as it always results in further work having to be done. Losing such a large area is detrimental to a tree, and topping only causes harm.
- Dead wood removal - this is done to stop die-back or decay spreading back into the sound wood and also for safety reasons, to stop the dead wood from falling
Any pruning cuts that are made should be clean cuts made with sharp tools. They should be made to a side shoot or back to the branch collar. The wound should be left open to the air and not painted with anything, as this can seal in disease. Trees have their own defence mechanisms against decay and, providing the pruning cuts are correctly made, and the tree is healthy, leaving the wound open is the best option.
British Standard 3998 (2012) gives recommendations and guidance on good pruning practice.
Woodland requires different management through its life. It varies depending upon the type of woodland - whether it is timber crop or amenity woodland. It is usually planted with transplants which are notch-planted between 2 to 3 metre centres. After about 10 years (although this may be more, depending upon species, ground type, elevation and exposure) the trees will need to be thinned, removing the less vigorous or bad form trees to allow development room for the best trees. Thinning should be in phases over a few decades until final spacing is achieved which varies depending upon species. For example, Birch will be closer spaced than Oak.
Remember, if you are considering doing some tree pruning or felling, you need to check that the tree is not protected by either Tree Preservation Order or by a Conservation Area. If the tree is protected you must apply to us in writing to get consent for the work before you start. if you don't get consent, you are committing an offence under the Town and Country Planning Act (1990).
Woodland work may require a Felling Licence - contact the Forestry Commission for advice.